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Commit ce9b97c7 authored by Andrey Kamaev's avatar Andrey Kamaev
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Fixed number of svn->git migration issues

parents 1852cb7e 5100ca75
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CMakeLists.txt
View file @ ce9b97c7
......@@ -285,25 +285,37 @@ ocv_include_directories(${OPENCV_CONFIG_FILE_INCLUDE_DIR})
# ----------------------------------------------------------------------------
# Autodetect if we are in a SVN repository
# ----------------------------------------------------------------------------
find_host_program(SVNVERSION_PATH svnversion)
mark_as_advanced(force SVNVERSION_PATH)
if(SVNVERSION_PATH)
message(STATUS "Extracting svn version, please wait...")
execute_process(COMMAND ${SVNVERSION_PATH} -n ${OpenCV_SOURCE_DIR} OUTPUT_VARIABLE SVNVERSION_RESULT)
if(SVNVERSION_RESULT MATCHES "exported")
# This is NOT a svn repository:
set(OPENCV_SVNVERSION "")
message(STATUS "SVNVERSION: exported")
else()
set(OPENCV_SVNVERSION " svn:${SVNVERSION_RESULT}")
message(STATUS "SVNVERSION: ${OPENCV_SVNVERSION}")
endif()
# Autodetect if we are in a GIT repository
# ----------------------------------------------------------------------------
# don't use FindGit because it requires CMake 2.8.2
set(git_names git eg) # eg = easy git
# Prefer .cmd variants on Windows unless running in a Makefile in the MSYS shell
if(WIN32)
if(NOT CMAKE_GENERATOR MATCHES "MSYS")
set(git_names git.cmd git eg.cmd eg)
endif()
endif()
find_host_program(GIT_EXECUTABLE NAMES ${git_names} PATH_SUFFIXES Git/cmd Git/bin DOC "git command line client")
mark_as_advanced(GIT_EXECUTABLE)
if(GIT_EXECUTABLE)
execute_process(COMMAND ${GIT_EXECUTABLE} rev-parse --short HEAD
WORKING_DIRECTORY "${OpenCV_SOURCE_DIR}"
OUTPUT_VARIABLE OPENCV_GIT_HASH_SORT
RESULT_VARIABLE GIT_RESULT
ERROR_QUIET
OUTPUT_STRIP_TRAILING_WHITESPACE
)
if(GIT_RESULT EQUAL 0)
set(OPENCV_VCSVERSION "commit:${OPENCV_GIT_HASH_SORT}")
else()
set(OPENCV_VCSVERSION "exported")
endif()
else()
# We don't have svnversion:
set(OPENCV_SVNVERSION "")
# We don't have git:
set(OPENCV_VCSVERSION "")
endif()
......@@ -474,8 +486,8 @@ include(cmake/OpenCVGenConfig.cmake REQUIRED)
# ----------------------------------------------------------------------------
status("")
status("General configuration for OpenCV ${OPENCV_VERSION} =====================================")
if(OPENCV_SVNVERSION)
status("Version control:" ${OPENCV_SVNVERSION})
if(OPENCV_VCSVERSION)
status(" Version control:" ${OPENCV_VCSVERSION})
endif()
# ========================== build platform ==========================
......
android/scripts/package.sh deleted 100644 → 0
View file @ 1852cb7e
#!/bin/sh
cd `dirname $0`/..
ANDROID_DIR=`pwd`
rm -rf package
mkdir -p package
cd package
PRG_DIR=`pwd`
mkdir opencv
# neon-enabled build
#cd $PRG_DIR
#mkdir build-neon
#cd build-neon
#cmake -DANDROID_ABI="armeabi-v7a with NEON" -DBUILD_DOCS=OFF -DBUILD_TESTS=OFF -DBUILD_EXAMPLES=OFF -DBUILD_ANDROID_EXAMPLES=OFF -DCMAKE_TOOLCHAIN_FILE="$ANDROID_DIR/android.toolchain.cmake" -DCMAKE_INSTALL_PREFIX="$PRG_DIR/opencv" "$ANDROID_DIR/.." || exit 1
#make -j8 install/strip || exit 1
#cd "$PRG_DIR/opencv"
#rm -rf doc include src .classpath .project AndroidManifest.xml default.properties share/OpenCV/haarcascades share/OpenCV/lbpcascades share/OpenCV/*.cmake share/OpenCV/OpenCV.mk
#mv libs/armeabi-v7a libs/armeabi-v7a-neon
#mv share/OpenCV/3rdparty/libs/armeabi-v7a share/OpenCV/3rdparty/libs/armeabi-v7a-neon
# armeabi-v7a build
cd "$PRG_DIR"
mkdir build
cd build
cmake -DANDROID_ABI="armeabi-v7a" -DBUILD_DOCS=OFF -DBUILD_TESTS=ON -DBUILD_EXAMPLES=OFF -DBUILD_ANDROID_EXAMPLES=ON -DCMAKE_TOOLCHAIN_FILE="$ANDROID_DIR/android.toolchain.cmake" -DCMAKE_INSTALL_PREFIX="$PRG_DIR/opencv" "$ANDROID_DIR/.." || exit 1
make -j8 install/strip || exit 1
cd "$PRG_DIR/opencv"
rm -rf doc include src .classpath .project AndroidManifest.xml default.properties project.properties share/OpenCV/haarcascades share/OpenCV/lbpcascades share/OpenCV/*.cmake share/OpenCV/OpenCV.mk
# armeabi build
cd "$PRG_DIR/build"
rm -rf CMakeCache.txt
cmake -DANDROID_ABI="armeabi" -DBUILD_DOCS=ON -DBUILD_TESTS=ON -DBUILD_EXAMPLES=OFF -DBUILD_ANDROID_EXAMPLES=ON -DINSTALL_ANDROID_EXAMPLES=ON -DCMAKE_TOOLCHAIN_FILE="$ANDROID_DIR/android.toolchain.cmake" -DCMAKE_INSTALL_PREFIX="$PRG_DIR/opencv" "$ANDROID_DIR/.." || exit 1
make -j8 install/strip docs || exit 1
find doc -name "*.pdf" -exec cp {} $PRG_DIR/opencv/doc \;
cd $PRG_DIR
rm -rf opencv/doc/CMakeLists.txt
cp "$ANDROID_DIR/README.android" opencv/
cp "$ANDROID_DIR/../README" opencv/
# get opencv version
CV_VERSION=`grep -o "[0-9]\+\.[0-9]\+\.[0-9]\+" opencv/share/OpenCV/OpenCVConfig-version.cmake`
OPENCV_NAME=OpenCV-$CV_VERSION
mv opencv $OPENCV_NAME
#samples
cp -r "$ANDROID_DIR/../samples/android" "$PRG_DIR/samples"
cd "$PRG_DIR/samples"
#enable for loops over items with spaces in their name
IFS="
"
for dir in `ls -1`
do
if [ -f "$dir/default.properties" ]
then
HAS_REFERENCE=`cat "$dir/project.properties" | grep -c android.library.reference.1`
if [ $HAS_REFERENCE = 1 ]
then
echo -n > "$dir/project.properties"
android update project --name "$dir" --target "android-8" --library "../../$OPENCV_NAME" --path "$dir"
#echo 'android update project --name "$dir" --target "android-8" --library "../opencv$CV_VERSION" --path "$dir"'
fi
else
if [ -f "$dir/default.properties" ]
then
HAS_REFERENCE=`cat "$dir/default.properties" | grep -c android.library.reference.1`
if [ $HAS_REFERENCE = 1 ]
then
echo -n > "$dir/default.properties"
android update project --name "$dir" --target "android-8" --library "../../$OPENCV_NAME" --path "$dir"
#echo 'android update project --name "$dir" --target "android-8" --library "../opencv$CV_VERSION" --path "$dir"'
fi
else
rm -rf "$dir"
fi
fi
done
echo "OPENCV_MK_PATH:=../../$OPENCV_NAME/share/OpenCV/OpenCV.mk" > includeOpenCV.mk
#clean samples
cd "$PRG_DIR/samples"
#remove ignored files/folders
svn status --no-ignore | grep ^I | cut -c9- | xargs -d \\n rm -rf
#remove unversioned files/folders
svn status | grep ^\? | cut -c9- | xargs -d \\n rm -rf
#generate "gen" folders to eliminate eclipse warnings
cd "$PRG_DIR/samples"
for dir in `ls -1`
do
if [ -d "$dir" ]
then
mkdir "$dir/gen"
fi
done
#generate folders "gen" and "res" for opencv (dummy eclipse stiff)
cd $PRG_DIR
mkdir "$OPENCV_NAME/gen"
mkdir "$OPENCV_NAME/res"
# pack all files
cd $PRG_DIR
PRG_NAME=OpenCV-$CV_VERSION-tp-android-bin.tar.bz2
tar cjpf $PRG_NAME --exclude-vcs $OPENCV_NAME samples || exit -1
echo
echo "Package $PRG_NAME is successfully created"
cmake/OpenCVExtraTargets.cmake
View file @ ce9b97c7
......@@ -10,7 +10,7 @@ ADD_CUSTOM_TARGET(uninstall "${CMAKE_COMMAND}" -P "${CMAKE_CURRENT_BINARY_DIR}/c
if(ENABLE_SOLUTION_FOLDERS)
set_target_properties(uninstall PROPERTIES FOLDER "CMakeTargets")
endif()
# ----------------------------------------------------------------------------
# Source package, for "make package_source"
......@@ -26,11 +26,11 @@ if(BUILD_PACKAGE)
set(TAR_TRANSFORM "\"s,^,${TARBALL_NAME}/,\"")
add_custom_target(package_source
#TODO: maybe we should not remove dll's
COMMAND ${TAR_CMD} --transform ${TAR_TRANSFORM} -cjpf ${CMAKE_CURRENT_BINARY_DIR}/${TARBALL_NAME}.tar.bz2 --exclude=".svn" --exclude="*.pyc" --exclude="*.vcproj" --exclude="*/lib/*" --exclude="*.dll" ./
COMMAND ${TAR_CMD} --transform ${TAR_TRANSFORM} -cjpf ${CMAKE_CURRENT_BINARY_DIR}/${TARBALL_NAME}.tar.bz2 --exclude=".svn" --exclude=".git" --exclude="*.pyc" --exclude="*.vcproj" --exclude="*/lib/*" --exclude="*.dll" ./
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
else()
add_custom_target(package_source
COMMAND zip -9 -r ${CMAKE_CURRENT_BINARY_DIR}/${TARBALL_NAME}.zip . -x '*/.svn/*' '*.vcproj' '*.pyc'
COMMAND zip -9 -r ${CMAKE_CURRENT_BINARY_DIR}/${TARBALL_NAME}.zip . -x '*/.svn/*' '*/.git/*' '*.vcproj' '*.pyc'
WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR})
endif()
if(ENABLE_SOLUTION_FOLDERS)
......
doc/opencv_cheatsheet.tex
View file @ ce9b97c7
This diff is collapsed.
doc/tutorials/core/basic_geometric_drawing/basic_geometric_drawing.rst
View file @ ce9b97c7
......@@ -9,7 +9,7 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use :point:`Point <>` to define 2D points in an image.
* Use :point:`Point <>` to define 2D points in an image.
* Use :scalar:`Scalar <>` and why it is useful
* Draw a **line** by using the OpenCV function :line:`line <>`
* Draw an **ellipse** by using the OpenCV function :ellipse:`ellipse <>`
......@@ -30,15 +30,15 @@ Point
It represents a 2D point, specified by its image coordinates :math:`x` and :math:`y`. We can define it as:
.. code-block:: cpp
Point pt;
pt.x = 10;
pt.x = 10;
pt.y = 8;
or
.. code-block:: cpp
Point pt = Point(10, 8);
Scalar
......@@ -48,7 +48,7 @@ Scalar
* Let's see an example, if we are asked for a color argument and we give:
.. code-block:: cpp
Scalar( a, b, c )
We would be defining a RGB color such as: *Red = c*, *Green = b* and *Blue = a*
......@@ -56,12 +56,12 @@ Scalar
Code
=====
* This code is in your OpenCV sample folder. Otherwise you can grab it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/core/Matrix/Drawing_1.cpp>`_
* This code is in your OpenCV sample folder. Otherwise you can grab it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/core/Matrix/Drawing_1.cpp>`_
Explanation
=============
#. Since we plan to draw two examples (an atom and a rook), we have to create 02 images and two windows to display them.
#. Since we plan to draw two examples (an atom and a rook), we have to create 02 images and two windows to display them.
.. code-block:: cpp
......@@ -69,7 +69,7 @@ Explanation
char atom_window[] = "Drawing 1: Atom";
char rook_window[] = "Drawing 2: Rook";
/// Create black empty images
/// Create black empty images
Mat atom_image = Mat::zeros( w, w, CV_8UC3 );
Mat rook_image = Mat::zeros( w, w, CV_8UC3 );
......@@ -79,7 +79,7 @@ Explanation
/// 1. Draw a simple atom:
/// 1.a. Creating ellipses
/// 1.a. Creating ellipses
MyEllipse( atom_image, 90 );
MyEllipse( atom_image, 0 );
MyEllipse( atom_image, 45 );
......@@ -105,7 +105,7 @@ Explanation
-1,
8 );
/// 2.c. Create a few lines
/// 2.c. Create a few lines
MyLine( rook_image, Point( 0, 15*w/16 ), Point( w, 15*w/16 ) );
MyLine( rook_image, Point( w/4, 7*w/8 ), Point( w/4, w ) );
MyLine( rook_image, Point( w/2, 7*w/8 ), Point( w/2, w ) );
......@@ -113,15 +113,15 @@ Explanation
#. Let's check what is inside each of these functions:
* *MyLine*
.. code-block:: cpp
* *MyLine*
.. code-block:: cpp
void MyLine( Mat img, Point start, Point end )
{
int thickness = 2;
int lineType = 8;
line( img,
line( img,
start,
end,
Scalar( 0, 0, 0 ),
......@@ -136,12 +136,12 @@ Explanation
* Draw a line from Point **start** to Point **end**
* The line is displayed in the image **img**
* The line color is defined by **Scalar( 0, 0, 0)** which is the RGB value correspondent to **Black**
* The line thickness is set to **thickness** (in this case 2)
* The line thickness is set to **thickness** (in this case 2)
* The line is a 8-connected one (**lineType** = 8)
* *MyEllipse*
.. code-block:: cpp
.. code-block:: cpp
void MyEllipse( Mat img, double angle )
{
......@@ -152,15 +152,15 @@ Explanation
Point( w/2.0, w/2.0 ),
Size( w/4.0, w/16.0 ),
angle,
0,
0,
360,
Scalar( 255, 0, 0 ),
thickness,
lineType );
lineType );
}
From the code above, we can observe that the function :ellipse:`ellipse <>` draws an ellipse such that:
.. container:: enumeratevisibleitemswithsquare
* The ellipse is displayed in the image **img**
......@@ -169,7 +169,7 @@ Explanation
* The ellipse extends an arc between **0** and **360** degrees
* The color of the figure will be **Scalar( 255, 255, 0)** which means blue in RGB value.
* The ellipse's **thickness** is 2.
* *MyFilledCircle*
......@@ -180,11 +180,11 @@ Explanation
int thickness = -1;
int lineType = 8;
circle( img,
circle( img,
center,
w/32.0,
Scalar( 0, 0, 255 ),
thickness,
thickness,
lineType );
}
......@@ -193,9 +193,9 @@ Explanation
.. container:: enumeratevisibleitemswithsquare
* The image where the circle will be displayed (**img**)
* The center of the circle denoted as the Point **center**
* The center of the circle denoted as the Point **center**
* The radius of the circle: **w/32.0**
* The color of the circle: **Scalar(0, 0, 255)** which means *Red* in BGR
* The color of the circle: **Scalar(0, 0, 255)** which means *Red* in BGR
* Since **thickness** = -1, the circle will be drawn filled.
* *MyPolygon*
......@@ -237,18 +237,18 @@ Explanation
npt,
1,
Scalar( 255, 255, 255 ),
lineType );
lineType );
}
To draw a filled polygon we use the function :fill_poly:`fillPoly <>`. We note that:
.. container:: enumeratevisibleitemswithsquare
* The polygon will be drawn on **img**
* The vertices of the polygon are the set of points in **ppt**
* The total number of vertices to be drawn are **npt**
* The number of polygons to be drawn is only **1**
* The color of the polygon is defined by **Scalar( 255, 255, 255)**, which is the BGR value for *white*
* The color of the polygon is defined by **Scalar( 255, 255, 255)**, which is the BGR value for *white*
* *rectangle*
......@@ -277,4 +277,4 @@ Compiling and running your program should give you a result like this:
.. image:: images/Drawing_1_Tutorial_Result_0.png
:alt: Drawing Tutorial 1 - Final Result
:align: center
:align: center
doc/tutorials/core/random_generator_and_text/random_generator_and_text.rst
View file @ ce9b97c7
......@@ -19,10 +19,10 @@ Code
.. container:: enumeratevisibleitemswithsquare
* In the previous tutorial (:ref:`Drawing_1`) we drew diverse geometric figures, giving as input parameters such as coordinates (in the form of :point:`Points <>`), color, thickness, etc. You might have noticed that we gave specific values for these arguments.
* In this tutorial, we intend to use *random* values for the drawing parameters. Also, we intend to populate our image with a big number of geometric figures. Since we will be initializing them in a random fashion, this process will be automatic and made by using *loops* .
* This code is in your OpenCV sample folder. Otherwise you can grab it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/core/Matrix/Drawing_2.cpp>`_ .
* This code is in your OpenCV sample folder. Otherwise you can grab it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/core/Matrix/Drawing_2.cpp>`_ .
Explanation
============
......@@ -43,7 +43,7 @@ Explanation
Mat image = Mat::zeros( window_height, window_width, CV_8UC3 );
/// Show it in a window during DELAY ms
imshow( window_name, image );
imshow( window_name, image );
#. Then we proceed to draw crazy stuff. After taking a look at the code, you can see that it is mainly divided in 8 sections, defined as functions:
......@@ -110,22 +110,22 @@ Explanation
* The *for* loop will repeat **NUMBER** times. Since the function :line:`line <>` is inside this loop, that means that **NUMBER** lines will be generated.
* The line extremes are given by *pt1* and *pt2*. For *pt1* we can see that:
.. code-block:: cpp
pt1.x = rng.uniform( x_1, x_2 );
pt1.x = rng.uniform( x_1, x_2 );
pt1.y = rng.uniform( y_1, y_2 );
* We know that **rng** is a *Random number generator* object. In the code above we are calling **rng.uniform(a,b)**. This generates a radombly uniformed distribution between the values **a** and **b** (inclusive in **a**, exclusive in **b**).
* We know that **rng** is a *Random number generator* object. In the code above we are calling **rng.uniform(a,b)**. This generates a radombly uniformed distribution between the values **a** and **b** (inclusive in **a**, exclusive in **b**).
* From the explanation above, we deduce that the extremes *pt1* and *pt2* will be random values, so the lines positions will be quite impredictable, giving a nice visual effect (check out the Result section below).
* As another observation, we notice that in the :line:`line <>` arguments, for the *color* input we enter:
.. code-block:: cpp
randomColor(rng)
randomColor(rng)
Let's check the function implementation:
.. code-block:: cpp
......@@ -138,7 +138,7 @@ Explanation
As we can see, the return value is an *Scalar* with 3 randomly initialized values, which are used as the *R*, *G* and *B* parameters for the line color. Hence, the color of the lines will be random too!
#. The explanation above applies for the other functions generating circles, ellipses, polygones, etc. The parameters such as *center* and *vertices* are also generated randomly.
#. The explanation above applies for the other functions generating circles, ellipses, polygones, etc. The parameters such as *center* and *vertices* are also generated randomly.
#. Before finishing, we also should take a look at the functions *Display_Random_Text* and *Displaying_Big_End*, since they both have a few interesting features:
......@@ -158,7 +158,7 @@ Explanation
putText( image, "Testing text rendering", org, rng.uniform(0,8),
rng.uniform(0,100)*0.05+0.1, randomColor(rng), rng.uniform(1, 10), lineType);
imshow( window_name, image );
if( waitKey(DELAY) >= 0 )
{ return -1; }
......@@ -172,7 +172,7 @@ Explanation
.. code-block:: cpp
putText( image, "Testing text rendering", org, rng.uniform(0,8),
rng.uniform(0,100)*0.05+0.1, randomColor(rng), rng.uniform(1, 10), lineType);
rng.uniform(0,100)*0.05+0.1, randomColor(rng), rng.uniform(1, 10), lineType);
So, what does the function :put_text:`putText <>` do? In our example:
......@@ -197,7 +197,7 @@ Explanation
Size textsize = getTextSize("OpenCV forever!", CV_FONT_HERSHEY_COMPLEX, 3, 5, 0);
Point org((window_width - textsize.width)/2, (window_height - textsize.height)/2);
int lineType = 8;
Mat image2;
for( int i = 0; i < 255; i += 2 )
......@@ -205,7 +205,7 @@ Explanation
image2 = image - Scalar::all(i);
putText( image2, "OpenCV forever!", org, CV_FONT_HERSHEY_COMPLEX, 3,
Scalar(i, i, 255), 5, lineType );
imshow( window_name, image2 );
if( waitKey(DELAY) >= 0 )
{ return -1; }
......@@ -222,8 +222,8 @@ Explanation
So, **image2** is the substraction of **image** and **Scalar::all(i)**. In fact, what happens here is that every pixel of **image2** will be the result of substracting every pixel of **image** minus the value of **i** (remember that for each pixel we are considering three values such as R, G and B, so each of them will be affected)
Also remember that the substraction operation *always* performs internally a **saturate** operation, which means that the result obtained will always be inside the allowed range (no negative and between 0 and 255 for our example).
Also remember that the substraction operation *always* performs internally a **saturate** operation, which means that the result obtained will always be inside the allowed range (no negative and between 0 and 255 for our example).
Result
========
......@@ -234,7 +234,7 @@ As you just saw in the Code section, the program will sequentially execute diver
.. image:: images/Drawing_2_Tutorial_Result_0.jpg
:alt: Drawing Tutorial 2 - Final Result 0
:align: center
:align: center
#. Then, a new set of figures, these time *rectangles* will follow.
......@@ -242,13 +242,13 @@ As you just saw in the Code section, the program will sequentially execute diver
.. image:: images/Drawing_2_Tutorial_Result_2.jpg
:alt: Drawing Tutorial 2 - Final Result 2
:align: center
:align: center
#. Now, *polylines* with 03 segments will appear on screen, again in random configurations.
.. image:: images/Drawing_2_Tutorial_Result_3.jpg
:alt: Drawing Tutorial 2 - Final Result 3
:align: center
:align: center
#. Filled polygons (in this example triangles) will follow.
......@@ -256,7 +256,7 @@ As you just saw in the Code section, the program will sequentially execute diver
.. image:: images/Drawing_2_Tutorial_Result_5.jpg
:alt: Drawing Tutorial 2 - Final Result 5
:align: center
:align: center
#. Near the end, the text *"Testing Text Rendering"* will appear in a variety of fonts, sizes, colors and positions.
......@@ -264,4 +264,4 @@ As you just saw in the Code section, the program will sequentially execute diver
.. image:: images/Drawing_2_Tutorial_Result_7.jpg
:alt: Drawing Tutorial 2 - Final Result 7
:align: center
:align: center
doc/tutorials/features2d/feature_description/feature_description.rst
View file @ ce9b97c7
......@@ -15,7 +15,7 @@ In this tutorial you will learn how to:
* Use :surf_descriptor_extractor:`SurfDescriptorExtractor<>` and its function :descriptor_extractor:`compute<>` to perform the required calculations.
* Use a :brute_force_matcher:`BruteForceMatcher<>` to match the features vector
* Use the function :draw_matches:`drawMatches<>` to draw the detected matches.
Theory
======
......@@ -23,9 +23,9 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/features2D/SURF_descriptor.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/features2D/SURF_descriptor.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include <stdio.h>
#include <iostream>
......@@ -45,7 +45,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
Mat img_1 = imread( argv[1], CV_LOAD_IMAGE_GRAYSCALE );
Mat img_2 = imread( argv[2], CV_LOAD_IMAGE_GRAYSCALE );
if( !img_1.data || !img_2.data )
{ return -1; }
......@@ -74,7 +74,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
//-- Draw matches
Mat img_matches;
drawMatches( img_1, keypoints_1, img_2, keypoints_2, matches, img_matches );
drawMatches( img_1, keypoints_1, img_2, keypoints_2, matches, img_matches );
//-- Show detected matches
imshow("Matches", img_matches );
......@@ -93,9 +93,9 @@ Explanation
Result
======
#. Here is the result after applying the BruteForce matcher between the two original images:
.. image:: images/Feature_Description_BruteForce_Result.jpg
:align: center
:height: 200pt
......
doc/tutorials/features2d/feature_detection/feature_detection.rst
View file @ ce9b97c7
......@@ -14,7 +14,7 @@ In this tutorial you will learn how to:
* Use the :surf_feature_detector:`SurfFeatureDetector<>` and its function :feature_detector_detect:`detect<>` to perform the detection process
* Use the function :draw_keypoints:`drawKeypoints<>` to draw the detected keypoints
Theory
======
......@@ -22,14 +22,14 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/features2D/SURF_detector.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/features2D/SURF_detector.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include <stdio.h>
#include <iostream>
#include "opencv2/core/core.hpp"
#include "opencv2/features2d/features2d.hpp"
#include "opencv2/features2d/features2d.hpp"
#include "opencv2/highgui/highgui.hpp"
using namespace cv;
......@@ -44,7 +44,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
Mat img_1 = imread( argv[1], CV_LOAD_IMAGE_GRAYSCALE );
Mat img_2 = imread( argv[2], CV_LOAD_IMAGE_GRAYSCALE );
if( !img_1.data || !img_2.data )
{ std::cout<< " --(!) Error reading images " << std::endl; return -1; }
......@@ -61,8 +61,8 @@ This tutorial code's is shown lines below. You can also download it from `here <
//-- Draw keypoints
Mat img_keypoints_1; Mat img_keypoints_2;
drawKeypoints( img_1, keypoints_1, img_keypoints_1, Scalar::all(-1), DrawMatchesFlags::DEFAULT );
drawKeypoints( img_2, keypoints_2, img_keypoints_2, Scalar::all(-1), DrawMatchesFlags::DEFAULT );
drawKeypoints( img_1, keypoints_1, img_keypoints_1, Scalar::all(-1), DrawMatchesFlags::DEFAULT );
drawKeypoints( img_2, keypoints_2, img_keypoints_2, Scalar::all(-1), DrawMatchesFlags::DEFAULT );
//-- Show detected (drawn) keypoints
imshow("Keypoints 1", img_keypoints_1 );
......@@ -82,9 +82,9 @@ Explanation
Result
======
#. Here is the result of the feature detection applied to the first image:
.. image:: images/Feature_Detection_Result_a.jpg
:align: center
:height: 125pt
......@@ -92,6 +92,6 @@ Result
#. And here is the result for the second image:
.. image:: images/Feature_Detection_Result_b.jpg
:align: center
:height: 200pt
:align: center
:height: 200pt
doc/tutorials/features2d/feature_flann_matcher/feature_flann_matcher.rst
View file @ ce9b97c7
......@@ -19,9 +19,9 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/features2D/SURF_FlannMatcher.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/features2D/SURF_FlannMatcher.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include <stdio.h>
#include <iostream>
......@@ -41,7 +41,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
Mat img_1 = imread( argv[1], CV_LOAD_IMAGE_GRAYSCALE );
Mat img_2 = imread( argv[2], CV_LOAD_IMAGE_GRAYSCALE );
if( !img_1.data || !img_2.data )
{ std::cout<< " --(!) Error reading images " << std::endl; return -1; }
......@@ -79,7 +79,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
printf("-- Max dist : %f \n", max_dist );
printf("-- Min dist : %f \n", min_dist );
//-- Draw only "good" matches (i.e. whose distance is less than 2*min_dist )
//-- PS.- radiusMatch can also be used here.
std::vector< DMatch > good_matches;
......@@ -87,13 +87,13 @@ This tutorial code's is shown lines below. You can also download it from `here <
for( int i = 0; i < descriptors_1.rows; i++ )
{ if( matches[i].distance < 2*min_dist )
{ good_matches.push_back( matches[i]); }
}
}
//-- Draw only "good" matches
Mat img_matches;
drawMatches( img_1, keypoints_1, img_2, keypoints_2,
good_matches, img_matches, Scalar::all(-1), Scalar::all(-1),
vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );
drawMatches( img_1, keypoints_1, img_2, keypoints_2,
good_matches, img_matches, Scalar::all(-1), Scalar::all(-1),
vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );
//-- Show detected matches
imshow( "Good Matches", img_matches );
......@@ -115,9 +115,9 @@ Explanation
Result
======
#. Here is the result of the feature detection applied to the first image:
.. image:: images/Featur_FlannMatcher_Result.jpg
:align: center
:height: 250pt
......
doc/tutorials/features2d/feature_homography/feature_homography.rst
View file @ ce9b97c7
......@@ -12,7 +12,7 @@ In this tutorial you will learn how to:
* Use the function :find_homography:`findHomography<>` to find the transform between matched keypoints.
* Use the function :perspective_transform:`perspectiveTransform<>` to map the points.
Theory
======
......@@ -20,9 +20,9 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/features2D/SURF_Homography.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/features2D/SURF_Homography.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include <stdio.h>
#include <iostream>
......@@ -43,7 +43,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
Mat img_object = imread( argv[1], CV_LOAD_IMAGE_GRAYSCALE );
Mat img_scene = imread( argv[2], CV_LOAD_IMAGE_GRAYSCALE );
if( !img_object.data || !img_scene.data )
{ std::cout<< " --(!) Error reading images " << std::endl; return -1; }
......@@ -81,21 +81,21 @@ This tutorial code's is shown lines below. You can also download it from `here <
printf("-- Max dist : %f \n", max_dist );
printf("-- Min dist : %f \n", min_dist );
//-- Draw only "good" matches (i.e. whose distance is less than 3*min_dist )
std::vector< DMatch > good_matches;
for( int i = 0; i < descriptors_object.rows; i++ )
{ if( matches[i].distance < 3*min_dist )
{ good_matches.push_back( matches[i]); }
}
}
Mat img_matches;
drawMatches( img_object, keypoints_object, img_scene, keypoints_scene,
good_matches, img_matches, Scalar::all(-1), Scalar::all(-1),
vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );
drawMatches( img_object, keypoints_object, img_scene, keypoints_scene,
good_matches, img_matches, Scalar::all(-1), Scalar::all(-1),
vector<char>(), DrawMatchesFlags::NOT_DRAW_SINGLE_POINTS );
//-- Localize the object
//-- Localize the object
std::vector<Point2f> obj;
std::vector<Point2f> scene;
......@@ -103,7 +103,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
{
//-- Get the keypoints from the good matches
obj.push_back( keypoints_object[ good_matches[i].queryIdx ].pt );
scene.push_back( keypoints_scene[ good_matches[i].trainIdx ].pt );
scene.push_back( keypoints_scene[ good_matches[i].trainIdx ].pt );
}
Mat H = findHomography( obj, scene, CV_RANSAC );
......@@ -143,6 +143,6 @@ Result
#. And here is the result for the detected object (highlighted in green)
.. image:: images/Feature_Homography_Result.jpg
:align: center
:height: 200pt
:align: center
:height: 200pt
doc/tutorials/features2d/trackingmotion/corner_subpixeles/corner_subpixeles.rst
View file @ ce9b97c7
......@@ -19,9 +19,9 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/TrackingMotion/cornerSubPix_Demo.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/TrackingMotion/cornerSubPix_Demo.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
......@@ -55,7 +55,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
namedWindow( source_window, CV_WINDOW_AUTOSIZE );
/// Create Trackbar to set the number of corners
createTrackbar( "Max corners:", source_window, &maxCorners, maxTrackbar, goodFeaturesToTrack_Demo);
createTrackbar( "Max corners:", source_window, &maxCorners, maxTrackbar, goodFeaturesToTrack_Demo);
imshow( source_window, src );
......@@ -72,7 +72,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
void goodFeaturesToTrack_Demo( int, void* )
{
if( maxCorners < 1 ) { maxCorners = 1; }
/// Parameters for Shi-Tomasi algorithm
vector<Point2f> corners;
double qualityLevel = 0.01;
......@@ -86,7 +86,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
copy = src.clone();
/// Apply corner detection
goodFeaturesToTrack( src_gray,
goodFeaturesToTrack( src_gray,
corners,
maxCorners,
qualityLevel,
......@@ -95,18 +95,18 @@ This tutorial code's is shown lines below. You can also download it from `here <
blockSize,
useHarrisDetector,
k );
/// Draw corners detected
cout<<"** Number of corners detected: "<<corners.size()<<endl;
int r = 4;
for( int i = 0; i < corners.size(); i++ )
{ circle( copy, corners[i], r, Scalar(rng.uniform(0,255), rng.uniform(0,255),
{ circle( copy, corners[i], r, Scalar(rng.uniform(0,255), rng.uniform(0,255),
rng.uniform(0,255)), -1, 8, 0 ); }
/// Show what you got
namedWindow( source_window, CV_WINDOW_AUTOSIZE );
imshow( source_window, copy );
imshow( source_window, copy );
/// Set the neeed parameters to find the refined corners
Size winSize = Size( 5, 5 );
......@@ -118,7 +118,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
/// Write them down
for( int i = 0; i < corners.size(); i++ )
{ cout<<" -- Refined Corner ["<<i<<"] ("<<corners[i].x<<","<<corners[i].y<<")"<<endl; }
{ cout<<" -- Refined Corner ["<<i<<"] ("<<corners[i].x<<","<<corners[i].y<<")"<<endl; }
}
......@@ -129,10 +129,10 @@ Result
======
.. image:: images/Corner_Subpixeles_Original_Image.jpg
:align: center
:align: center
Here is the result:
.. image:: images/Corner_Subpixeles_Result.jpg
:align: center
:align: center
doc/tutorials/features2d/trackingmotion/generic_corner_detector/generic_corner_detector.rst
View file @ ce9b97c7
......@@ -11,7 +11,7 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV function :corner_eigenvals_and_vecs:`cornerEigenValsAndVecs <>` to find the eigenvalues and eigenvectors to determine if a pixel is a corner.
* Use the OpenCV function :corner_min_eigenval:`cornerMinEigenVal <>` to find the minimum eigenvalues for corner detection.
* Use the OpenCV function :corner_min_eigenval:`cornerMinEigenVal <>` to find the minimum eigenvalues for corner detection.
* To implement our own version of the Harris detector as well as the Shi-Tomasi detector, by using the two functions above.
Theory
......@@ -20,9 +20,9 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/TrackingMotion/cornerDetector_Demo.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/TrackingMotion/cornerDetector_Demo.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
......@@ -34,9 +34,9 @@ This tutorial code's is shown lines below. You can also download it from `here <
using namespace std;
/// Global variables
Mat src, src_gray;
Mat src, src_gray;
Mat myHarris_dst; Mat myHarris_copy; Mat Mc;
Mat myShiTomasi_dst; Mat myShiTomasi_copy;
Mat myShiTomasi_dst; Mat myShiTomasi_copy;
int myShiTomasi_qualityLevel = 50;
int myHarris_qualityLevel = 50;
......@@ -70,7 +70,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
cornerEigenValsAndVecs( src_gray, myHarris_dst, blockSize, apertureSize, BORDER_DEFAULT );
/* calculate Mc */
/* calculate Mc */
for( int j = 0; j < src_gray.rows; j++ )
{ for( int i = 0; i < src_gray.cols; i++ )
{
......@@ -81,25 +81,25 @@ This tutorial code's is shown lines below. You can also download it from `here <
}
minMaxLoc( Mc, &myHarris_minVal, &myHarris_maxVal, 0, 0, Mat() );
/* Create Window and Trackbar */
namedWindow( myHarris_window, CV_WINDOW_AUTOSIZE );
createTrackbar( " Quality Level:", myHarris_window, &myHarris_qualityLevel, max_qualityLevel,
myHarris_function );
createTrackbar( " Quality Level:", myHarris_window, &myHarris_qualityLevel, max_qualityLevel,
myHarris_function );
myHarris_function( 0, 0 );
/// My Shi-Tomasi -- Using cornerMinEigenVal
myShiTomasi_dst = Mat::zeros( src_gray.size(), CV_32FC1 );
myShiTomasi_dst = Mat::zeros( src_gray.size(), CV_32FC1 );
cornerMinEigenVal( src_gray, myShiTomasi_dst, blockSize, apertureSize, BORDER_DEFAULT );
minMaxLoc( myShiTomasi_dst, &myShiTomasi_minVal, &myShiTomasi_maxVal, 0, 0, Mat() );
/* Create Window and Trackbar */
namedWindow( myShiTomasi_window, CV_WINDOW_AUTOSIZE );
createTrackbar( " Quality Level:", myShiTomasi_window, &myShiTomasi_qualityLevel, max_qualityLevel,
myShiTomasi_function );
namedWindow( myShiTomasi_window, CV_WINDOW_AUTOSIZE );
createTrackbar( " Quality Level:", myShiTomasi_window, &myShiTomasi_qualityLevel, max_qualityLevel,
myShiTomasi_function );
myShiTomasi_function( 0, 0 );
waitKey(0);
return(0);
}
......@@ -114,9 +114,9 @@ This tutorial code's is shown lines below. You can also download it from `here <
for( int j = 0; j < src_gray.rows; j++ )
{ for( int i = 0; i < src_gray.cols; i++ )
{
if( myShiTomasi_dst.at<float>(j,i) > myShiTomasi_minVal + ( myShiTomasi_maxVal -
if( myShiTomasi_dst.at<float>(j,i) > myShiTomasi_minVal + ( myShiTomasi_maxVal -
myShiTomasi_minVal )*myShiTomasi_qualityLevel/max_qualityLevel )
{ circle( myShiTomasi_copy, Point(i,j), 4, Scalar( rng.uniform(0,255),
{ circle( myShiTomasi_copy, Point(i,j), 4, Scalar( rng.uniform(0,255),
rng.uniform(0,255), rng.uniform(0,255) ), -1, 8, 0 ); }
}
}
......@@ -135,9 +135,9 @@ This tutorial code's is shown lines below. You can also download it from `here <
{
if( Mc.at<float>(j,i) > myHarris_minVal + ( myHarris_maxVal - myHarris_minVal )
*myHarris_qualityLevel/max_qualityLevel )
{ circle( myHarris_copy, Point(i,j), 4, Scalar( rng.uniform(0,255), rng.uniform(0,255),
{ circle( myHarris_copy, Point(i,j), 4, Scalar( rng.uniform(0,255), rng.uniform(0,255),
rng.uniform(0,255) ), -1, 8, 0 ); }
}
}
}
imshow( myHarris_window, myHarris_copy );
}
......@@ -151,9 +151,9 @@ Result
======
.. image:: images/My_Harris_corner_detector_Result.jpg
:align: center
:align: center
.. image:: images/My_Shi_Tomasi_corner_detector_Result.jpg
:align: center
:align: center
doc/tutorials/features2d/trackingmotion/good_features_to_track/good_features_to_track.rst
View file @ ce9b97c7
......@@ -18,9 +18,9 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/TrackingMotion/goodFeaturesToTrack_Demo.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/TrackingMotion/goodFeaturesToTrack_Demo.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
......@@ -56,7 +56,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
namedWindow( source_window, CV_WINDOW_AUTOSIZE );
/// Create Trackbar to set the number of corners
createTrackbar( "Max corners:", source_window, &maxCorners, maxTrackbar, goodFeaturesToTrack_Demo );
createTrackbar( "Max corners:", source_window, &maxCorners, maxTrackbar, goodFeaturesToTrack_Demo );
imshow( source_window, src );
......@@ -70,10 +70,10 @@ This tutorial code's is shown lines below. You can also download it from `here <
* @function goodFeaturesToTrack_Demo.cpp
* @brief Apply Shi-Tomasi corner detector
*/
void goodFeaturesToTrack_Demo( int, void* )
void goodFeaturesToTrack_Demo( int, void* )
{
if( maxCorners < 1 ) { maxCorners = 1; }
/// Parameters for Shi-Tomasi algorithm
vector<Point2f> corners;
double qualityLevel = 0.01;
......@@ -87,7 +87,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
copy = src.clone();
/// Apply corner detection
goodFeaturesToTrack( src_gray,
goodFeaturesToTrack( src_gray,
corners,
maxCorners,
qualityLevel,
......@@ -96,18 +96,18 @@ This tutorial code's is shown lines below. You can also download it from `here <
blockSize,
useHarrisDetector,
k );
/// Draw corners detected
cout<<"** Number of corners detected: "<<corners.size()<<endl;
int r = 4;
for( int i = 0; i < corners.size(); i++ )
{ circle( copy, corners[i], r, Scalar(rng.uniform(0,255), rng.uniform(0,255),
{ circle( copy, corners[i], r, Scalar(rng.uniform(0,255), rng.uniform(0,255),
rng.uniform(0,255)), -1, 8, 0 ); }
/// Show what you got
namedWindow( source_window, CV_WINDOW_AUTOSIZE );
imshow( source_window, copy );
imshow( source_window, copy );
}
Explanation
......@@ -117,6 +117,6 @@ Result
======
.. image:: images/Feature_Detection_Result_a.jpg
:align: center
:align: center
doc/tutorials/features2d/trackingmotion/harris_detector/harris_detector.rst
View file @ ce9b97c7
......@@ -10,7 +10,7 @@ In this tutorial you will learn:
.. container:: enumeratevisibleitemswithsquare
* What features are and why they are important
* What features are and why they are important
* Use the function :corner_harris:`cornerHarris <>` to detect corners using the Harris-Stephens method.
Theory
......@@ -56,7 +56,7 @@ How does it work?
.. container:: enumeratevisibleitemswithsquare
* Let's look for corners. Since corners represents a variation in the gradient in the image, we will look for this "variation".
* Let's look for corners. Since corners represents a variation in the gradient in the image, we will look for this "variation".
* Consider a grayscale image :math:`I`. We are going to sweep a window :math:`w(x,y)` (with displacements :math:`u` in the x direction and :math:`v` in the right direction) :math:`I` and will calculate the variation of intensity.
......@@ -66,10 +66,10 @@ How does it work?
where:
* :math:`w(x,y)` is the window at position :math:`(x,y)`
* :math:`w(x,y)` is the window at position :math:`(x,y)`
* :math:`I(x,y)` is the intensity at :math:`(x,y)`
* :math:`I(x+u,y+v)` is the intensity at the moved window :math:`(x+u,y+v)`
* Since we are looking for windows with corners, we are looking for windows with a large variation in intensity. Hence, we have to maximize the equation above, specifically the term:
.. math::
......@@ -89,36 +89,36 @@ How does it work?
.. math::
E(u,v) \approx \sum _{x,y} u^{2}I_{x}^{2} + 2uvI_{x}I_{y} + v^{2}I_{y}^{2}
* Which can be expressed in a matrix form as:
.. math::
E(u,v) \approx \begin{bmatrix}
u & v
u & v
\end{bmatrix}
\left (
\displaystyle \sum_{x,y}
w(x,y)
\begin{bmatrix}
I_x^{2} & I_{x}I_{y} \\
I_xI_{y} & I_{y}^{2}
I_xI_{y} & I_{y}^{2}
\end{bmatrix}
\right )
\right )
\begin{bmatrix}
u \\
v
\end{bmatrix}
v
\end{bmatrix}
* Let's denote:
.. math::
M = \displaystyle \sum_{x,y}
w(x,y)
w(x,y)
\begin{bmatrix}
I_x^{2} & I_{x}I_{y} \\
I_xI_{y} & I_{y}^{2}
I_xI_{y} & I_{y}^{2}
\end{bmatrix}
* So, our equation now is:
......@@ -126,34 +126,34 @@ How does it work?
.. math::
E(u,v) \approx \begin{bmatrix}
u & v
u & v
\end{bmatrix}
M
\begin{bmatrix}
u \\
v
\end{bmatrix}
v
\end{bmatrix}
* A score is calculated for each window, to determine if it can possibly contain a corner:
.. math::
R = det(M) - k(trace(M))^{2}
R = det(M) - k(trace(M))^{2}
where:
* det(M) = :math:`\lambda_{1}\lambda_{2}`
* trace(M) = :math:`\lambda_{1}+\lambda_{2}`
a window with a score :math:`R` greater than a certain value is considered a "corner"
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/TrackingMotion/cornerHarris_Demo.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/TrackingMotion/cornerHarris_Demo.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
......@@ -161,7 +161,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
#include <stdio.h>
#include <stdlib.h>
using namespace cv;
using namespace cv;
using namespace std;
/// Global variables
......@@ -186,7 +186,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
namedWindow( source_window, CV_WINDOW_AUTOSIZE );
createTrackbar( "Threshold: ", source_window, &thresh, max_thresh, cornerHarris_demo );
imshow( source_window, src );
cornerHarris_demo( 0, 0 );
waitKey(0);
......@@ -204,25 +204,25 @@ This tutorial code's is shown lines below. You can also download it from `here <
int blockSize = 2;
int apertureSize = 3;
double k = 0.04;
/// Detecting corners
cornerHarris( src_gray, dst, blockSize, apertureSize, k, BORDER_DEFAULT );
/// Normalizing
normalize( dst, dst_norm, 0, 255, NORM_MINMAX, CV_32FC1, Mat() );
convertScaleAbs( dst_norm, dst_norm_scaled );
convertScaleAbs( dst_norm, dst_norm_scaled );
/// Drawing a circle around corners
for( int j = 0; j < dst_norm.rows ; j++ )
{ for( int i = 0; i < dst_norm.cols; i++ )
{
if( (int) dst_norm.at<float>(j,i) > thresh )
{
circle( dst_norm_scaled, Point( i, j ), 5, Scalar(0), 2, 8, 0 );
{
circle( dst_norm_scaled, Point( i, j ), 5, Scalar(0), 2, 8, 0 );
}
}
}
/// Showing the result
}
}
/// Showing the result
namedWindow( corners_window, CV_WINDOW_AUTOSIZE );
imshow( corners_window, dst_norm_scaled );
}
......@@ -237,11 +237,11 @@ Result
The original image:
.. image:: images/Harris_Detector_Original_Image.jpg
:align: center
:align: center
The detected corners are surrounded by a small black circle
.. image:: images/Harris_Detector_Result.jpg
:align: center
:align: center
doc/tutorials/imgproc/erosion_dilatation/erosion_dilatation.rst
View file @ ce9b97c7
......@@ -22,7 +22,7 @@ Cool Theory
Morphological Operations
--------------------------
* In short: A set of operations that process images based on shapes. Morphological operations apply a *structuring element* to an input image and generate an output image.
* In short: A set of operations that process images based on shapes. Morphological operations apply a *structuring element* to an input image and generate an output image.
* The most basic morphological operations are two: Erosion and Dilation. They have a wide array of uses, i.e. :
......@@ -36,7 +36,7 @@ Morphological Operations
.. image:: images/Morphology_1_Tutorial_Theory_Original_Image.png
:alt: Original image
:align: center
:align: center
Dilation
^^^^^^^^^
......@@ -49,7 +49,7 @@ Dilation
.. image:: images/Morphology_1_Tutorial_Theory_Dilation.png
:alt: Dilation result - Theory example
:align: center
:align: center
The background (bright) dilates around the black regions of the letter.
......@@ -58,21 +58,21 @@ Erosion
* This operation is the sister of dilation. What this does is to compute a local minimum over the area of the kernel.
* As the kernel :math:`B` is scanned over the image, we compute the minimal pixel value overlapped by :math:`B` and replace the image pixel under the anchor point with that minimal value.
* As the kernel :math:`B` is scanned over the image, we compute the minimal pixel value overlapped by :math:`B` and replace the image pixel under the anchor point with that minimal value.
* Analagously to the example for dilation, we can apply the erosion operator to the original image (shown above). You can see in the result below that the bright areas of the image (the background, apparently), get thinner, whereas the dark zones (the "writing"( gets bigger.
.. image:: images/Morphology_1_Tutorial_Theory_Erosion.png
:alt: Erosion result - Theory example
:align: center
:align: center
Code
======
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgProc/Morphology_1.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgProc/Morphology_1.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
......@@ -104,29 +104,29 @@ This tutorial code's is shown lines below. You can also download it from `here <
if( !src.data )
{ return -1; }
/// Create windows
namedWindow( "Erosion Demo", CV_WINDOW_AUTOSIZE );
namedWindow( "Dilation Demo", CV_WINDOW_AUTOSIZE );
cvMoveWindow( "Dilation Demo", src.cols, 0 );
/// Create Erosion Trackbar
createTrackbar( "Element:\n 0: Rect \n 1: Cross \n 2: Ellipse", "Erosion Demo",
&erosion_elem, max_elem,
createTrackbar( "Element:\n 0: Rect \n 1: Cross \n 2: Ellipse", "Erosion Demo",
&erosion_elem, max_elem,
Erosion );
createTrackbar( "Kernel size:\n 2n +1", "Erosion Demo",
createTrackbar( "Kernel size:\n 2n +1", "Erosion Demo",
&erosion_size, max_kernel_size,
Erosion );
/// Create Dilation Trackbar
createTrackbar( "Element:\n 0: Rect \n 1: Cross \n 2: Ellipse", "Dilation Demo",
&dilation_elem, max_elem,
createTrackbar( "Element:\n 0: Rect \n 1: Cross \n 2: Ellipse", "Dilation Demo",
&dilation_elem, max_elem,
Dilation );
createTrackbar( "Kernel size:\n 2n +1", "Dilation Demo",
createTrackbar( "Kernel size:\n 2n +1", "Dilation Demo",
&dilation_size, max_kernel_size,
Dilation );
Dilation );
/// Default start
Erosion( 0, 0 );
......@@ -144,13 +144,13 @@ This tutorial code's is shown lines below. You can also download it from `here <
else if( erosion_elem == 1 ){ erosion_type = MORPH_CROSS; }
else if( erosion_elem == 2) { erosion_type = MORPH_ELLIPSE; }
Mat element = getStructuringElement( erosion_type,
Mat element = getStructuringElement( erosion_type,
Size( 2*erosion_size + 1, 2*erosion_size+1 ),
Point( erosion_size, erosion_size ) );
Point( erosion_size, erosion_size ) );
/// Apply the erosion operation
erode( src, erosion_dst, element );
imshow( "Erosion Demo", erosion_dst );
imshow( "Erosion Demo", erosion_dst );
}
/** @function Dilation */
......@@ -161,12 +161,12 @@ This tutorial code's is shown lines below. You can also download it from `here <
else if( dilation_elem == 1 ){ dilation_type = MORPH_CROSS; }
else if( dilation_elem == 2) { dilation_type = MORPH_ELLIPSE; }
Mat element = getStructuringElement( dilation_type,
Mat element = getStructuringElement( dilation_type,
Size( 2*dilation_size + 1, 2*dilation_size+1 ),
Point( dilation_size, dilation_size ) );
Point( dilation_size, dilation_size ) );
/// Apply the dilation operation
dilate( src, dilation_dst, element );
imshow( "Dilation Demo", dilation_dst );
imshow( "Dilation Demo", dilation_dst );
}
......@@ -182,12 +182,12 @@ Explanation
* Create a set of 02 Trackbars for each operation:
* The first trackbar "Element" returns either **erosion_elem** or **dilation_elem**
* The second trackbar "Kernel size" return **erosion_size** or **dilation_size** for the corresponding operation.
* The second trackbar "Kernel size" return **erosion_size** or **dilation_size** for the corresponding operation.
* Every time we move any slider, the user's function **Erosion** or **Dilation** will be called and it will update the output image based on the current trackbar values.
Let's analyze these two functions:
#. **erosion:**
.. code-block:: cpp
......@@ -200,32 +200,32 @@ Explanation
else if( erosion_elem == 1 ){ erosion_type = MORPH_CROSS; }
else if( erosion_elem == 2) { erosion_type = MORPH_ELLIPSE; }
Mat element = getStructuringElement( erosion_type,
Mat element = getStructuringElement( erosion_type,
Size( 2*erosion_size + 1, 2*erosion_size+1 ),
Point( erosion_size, erosion_size ) );
Point( erosion_size, erosion_size ) );
/// Apply the erosion operation
erode( src, erosion_dst, element );
imshow( "Erosion Demo", erosion_dst );
imshow( "Erosion Demo", erosion_dst );
}
* The function that performs the *erosion* operation is :erode:`erode <>`. As we can see, it receives three arguments:
* *src*: The source image
* *erosion_dst*: The output image
* *element*: This is the kernel we will use to perform the operation. If we do not specify, the default is a simple :math:`3x3` matrix. Otherwise, we can specify its shape. For this, we need to use the function :get_structuring_element:`getStructuringElement <>`:
.. code-block:: cpp
Mat element = getStructuringElement( erosion_type,
Mat element = getStructuringElement( erosion_type,
Size( 2*erosion_size + 1, 2*erosion_size+1 ),
Point( erosion_size, erosion_size ) );
Point( erosion_size, erosion_size ) );
We can choose any of three shapes for our kernel:
.. container:: enumeratevisibleitemswithsquare
+ Rectangular box: MORPH_RECT
+ Cross: MORPH_CROSS
+ Cross: MORPH_CROSS
+ Ellipse: MORPH_ELLIPSE
Then, we just have to specify the size of our kernel and the *anchor point*. If not specified, it is assumed to be in the center.
......@@ -233,8 +233,8 @@ Explanation
* That is all. We are ready to perform the erosion of our image.
.. note::
Additionally, there is another parameter that allows you to perform multiple erosions (iterations) at once. We are not using it in this simple tutorial, though. You can check out the Reference for more details.
Additionally, there is another parameter that allows you to perform multiple erosions (iterations) at once. We are not using it in this simple tutorial, though. You can check out the Reference for more details.
#. **dilation:**
......@@ -250,12 +250,12 @@ The code is below. As you can see, it is completely similar to the snippet of co
else if( dilation_elem == 1 ){ dilation_type = MORPH_CROSS; }
else if( dilation_elem == 2) { dilation_type = MORPH_ELLIPSE; }
Mat element = getStructuringElement( dilation_type,
Mat element = getStructuringElement( dilation_type,
Size( 2*dilation_size + 1, 2*dilation_size+1 ),
Point( dilation_size, dilation_size ) );
Point( dilation_size, dilation_size ) );
/// Apply the dilation operation
dilate( src, dilation_dst, element );
imshow( "Dilation Demo", dilation_dst );
imshow( "Dilation Demo", dilation_dst );
}
......@@ -267,10 +267,10 @@ Results
.. image:: images/Morphology_1_Tutorial_Original_Image.jpg
:alt: Original image
:align: center
:align: center
We get the results below. Varying the indices in the Trackbars give different output images, naturally. Try them out! You can even try to add a third Trackbar to control the number of iterations.
.. image:: images/Morphology_1_Tutorial_Cover.jpg
:alt: Dilation and Erosion application
:align: center
:align: center
doc/tutorials/imgproc/gausian_median_blur_bilateral_filter/gausian_median_blur_bilateral_filter.rst
View file @ ce9b97c7
......@@ -19,11 +19,11 @@ Theory
======
.. note::
The explanation below belongs to the book `Computer Vision: Algorithms and Applications <http://szeliski.org/Book/>`_ by Richard Szeliski and to *LearningOpenCV*
The explanation below belongs to the book `Computer Vision: Algorithms and Applications <http://szeliski.org/Book/>`_ by Richard Szeliski and to *LearningOpenCV*
.. container:: enumeratevisibleitemswithsquare
* *Smoothing*, also called *blurring*, is a simple and frequently used image processing operation.
* *Smoothing*, also called *blurring*, is a simple and frequently used image processing operation.
* There are many reasons for smoothing. In this tutorial we will focus on smoothing in order to reduce noise (other uses will be seen in the following tutorials).
......@@ -33,7 +33,7 @@ Theory
g(i,j) = \sum_{k,l} f(i+k, j+l) h(k,l)
:math:`h(k,l)` is called the *kernel*, which is nothing more than the coefficients of the filter.
It helps to visualize a *filter* as a window of coefficients sliding across the image.
......@@ -44,19 +44,19 @@ Normalized Box Filter
.. container:: enumeratevisibleitemswithsquare
* This filter is the simplest of all! Each output pixel is the *mean* of its kernel neighbors ( all of them contribute with equal weights)
* This filter is the simplest of all! Each output pixel is the *mean* of its kernel neighbors ( all of them contribute with equal weights)
* The kernel is below:
.. math::
K = \dfrac{1}{K_{width} \cdot K_{height}} \begin{bmatrix}
1 & 1 & 1 & ... & 1 \\
1 & 1 & 1 & ... & 1 \\
. & . & . & ... & 1 \\
. & . & . & ... & 1 \\
1 & 1 & 1 & ... & 1
\end{bmatrix}
\end{bmatrix}
Gaussian Filter
......@@ -69,16 +69,16 @@ Gaussian Filter
* Just to make the picture clearer, remember how a 1D Gaussian kernel look like?
.. image:: images/Smoothing_Tutorial_theory_gaussian_0.jpg
:align: center
:align: center
Assuming that an image is 1D, you can notice that the pixel located in the middle would have the biggest weight. The weight of its neighbors decreases as the spatial distance between them and the center pixel increases.
Assuming that an image is 1D, you can notice that the pixel located in the middle would have the biggest weight. The weight of its neighbors decreases as the spatial distance between them and the center pixel increases.
.. note::
Remember that a 2D Gaussian can be represented as :
.. math::
G_{0}(x, y) = A e^{ \dfrac{ -(x - \mu_{x})^{2} }{ 2\sigma^{2}_{x} } + \dfrac{ -(y - \mu_{y})^{2} }{ 2\sigma^{2}_{y} } }
where :math:`\mu` is the mean (the peak) and :math:`\sigma` represents the variance (per each of the variables :math:`x` and :math:`y`)
......@@ -97,9 +97,9 @@ Bilateral Filter
* So far, we have explained some filters which main goal is to *smooth* an input image. However, sometimes the filters do not only dissolve the noise, but also smooth away the *edges*. To avoid this (at certain extent at least), we can use a bilateral filter.
* In an analogous way as the Gaussian filter, the bilateral filter also considers the neighboring pixels with weights assigned to each of them. These weights have two components, the first of which is the same weighting used by the Gaussian filter. The second component takes into account the difference in intensity between the neighboring pixels and the evaluated one.
* In an analogous way as the Gaussian filter, the bilateral filter also considers the neighboring pixels with weights assigned to each of them. These weights have two components, the first of which is the same weighting used by the Gaussian filter. The second component takes into account the difference in intensity between the neighboring pixels and the evaluated one.
* For a more detailed explanation you can check `this link <http://homepages.inf.ed.ac.uk/rbf/CVonline/LOCAL_COPIES/MANDUCHI1/Bilateral_Filtering.html>`_
* For a more detailed explanation you can check `this link <http://homepages.inf.ed.ac.uk/rbf/CVonline/LOCAL_COPIES/MANDUCHI1/Bilateral_Filtering.html>`_
Code
......@@ -108,14 +108,14 @@ Code
.. container:: enumeratevisibleitemswithsquare
* **What does this program do?**
.. container:: enumeratevisibleitemswithsquare
* Loads an image
* Applies 4 different kinds of filters (explained in Theory) and show the filtered images sequentially
* **Downloadable code**:
Click `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgProc/Smoothing.cpp>`_
Click `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgProc/Smoothing.cpp>`_
* **Code at glance:**
......@@ -140,29 +140,29 @@ Code
int display_caption( char* caption );
int display_dst( int delay );
/**
* function main
/**
* function main
*/
int main( int argc, char** argv )
int main( int argc, char** argv )
{
namedWindow( window_name, CV_WINDOW_AUTOSIZE );
/// Load the source image
src = imread( "../images/lena.jpg", 1 );
src = imread( "../images/lena.jpg", 1 );
if( display_caption( "Original Image" ) != 0 ) { return 0; }
dst = src.clone();
if( display_dst( DELAY_CAPTION ) != 0 ) { return 0; }
/// Applying Homogeneous blur
/// Applying Homogeneous blur
if( display_caption( "Homogeneous Blur" ) != 0 ) { return 0; }
for ( int i = 1; i < MAX_KERNEL_LENGTH; i = i + 2 )
{ blur( src, dst, Size( i, i ), Point(-1,-1) );
if( display_dst( DELAY_BLUR ) != 0 ) { return 0; } }
/// Applying Gaussian blur
/// Applying Gaussian blur
if( display_caption( "Gaussian Blur" ) != 0 ) { return 0; }
for ( int i = 1; i < MAX_KERNEL_LENGTH; i = i + 2 )
......@@ -193,8 +193,8 @@ Code
int display_caption( char* caption )
{
dst = Mat::zeros( src.size(), src.type() );
putText( dst, caption,
Point( src.cols/4, src.rows/2),
putText( dst, caption,
Point( src.cols/4, src.rows/2),
CV_FONT_HERSHEY_COMPLEX, 1, Scalar(255, 255, 255) );
imshow( window_name, dst );
......@@ -208,7 +208,7 @@ Code
imshow( window_name, dst );
int c = waitKey ( delay );
if( c >= 0 ) { return -1; }
return 0;
return 0;
}
......@@ -216,7 +216,7 @@ Code
Explanation
=============
#. Let's check the OpenCV functions that involve only the smoothing procedure, since the rest is already known by now.
#. Let's check the OpenCV functions that involve only the smoothing procedure, since the rest is already known by now.
#. **Normalized Block Filter:**
......@@ -237,10 +237,10 @@ Explanation
+ *dst*: Destination image
+ *Size( w,h )*: Defines the size of the kernel to be used ( of width *w* pixels and height *h* pixels)
+ *Size( w,h )*: Defines the size of the kernel to be used ( of width *w* pixels and height *h* pixels)
+ *Point(-1, -1)*: Indicates where the anchor point (the pixel evaluated) is located with respect to the neighborhood. If there is a negative value, then the center of the kernel is considered the anchor point.
+ *Point(-1, -1)*: Indicates where the anchor point (the pixel evaluated) is located with respect to the neighborhood. If there is a negative value, then the center of the kernel is considered the anchor point.
#. **Gaussian Filter:**
It is performed by the function :gaussian_blur:`GaussianBlur <>` :
......@@ -262,9 +262,9 @@ Explanation
+ *Size(w, h)*: The size of the kernel to be used (the neighbors to be considered). :math:`w` and :math:`h` have to be odd and positive numbers otherwise thi size will be calculated using the :math:`\sigma_{x}` and :math:`\sigma_{y}` arguments.
+ :math:`\sigma_{x}`: The standard deviation in x. Writing :math:`0` implies that :math:`\sigma_{x}` is calculated using kernel size.
+ :math:`\sigma_{y}`: The standard deviation in y. Writing :math:`0` implies that :math:`\sigma_{y}` is calculated using kernel size.
#. **Median Filter:**
......@@ -283,12 +283,12 @@ Explanation
+ *src*: Source image
+ *dst*: Destination image, must be the same type as *src*
+ *i*: Size of the kernel (only one because we use a square window). Must be odd.
+ *i*: Size of the kernel (only one because we use a square window). Must be odd.
#. **Bilateral Filter**
Provided by OpenCV function :bilateral_filter:`bilateralFilter <>`
.. code-block:: cpp
......@@ -296,7 +296,7 @@ Explanation
for ( int i = 1; i < MAX_KERNEL_LENGTH; i = i + 2 )
{ bilateralFilter ( src, dst, i, i*2, i/2 );
if( display_dst( DELAY_BLUR ) != 0 ) { return 0; } }
We use 5 arguments:
.. container:: enumeratevisibleitemswithsquare
......@@ -306,9 +306,9 @@ Explanation
+ *dst*: Destination image
+ *d*: The diameter of each pixel neighborhood.
+ :math:`\sigma_{Color}`: Standard deviation in the color space.
+ :math:`\sigma_{Space}`: Standard deviation in the coordinate space (in pixel terms)
......@@ -317,10 +317,10 @@ Results
.. container:: enumeratevisibleitemswithsquare
* The code opens an image (in this case *lena.jpg*) and display it under the effects of the 4 filters explained.
* The code opens an image (in this case *lena.jpg*) and display it under the effects of the 4 filters explained.
* Here is a snapshot of the image smoothed using *medianBlur*:
.. image:: images/Smoothing_Tutorial_Result_Median_Filter.jpg
:alt: Smoothing with a median filter
:align: center
:align: center
doc/tutorials/imgproc/histograms/back_projection/back_projection.rst
View file @ ce9b97c7
......@@ -14,7 +14,7 @@ In this tutorial you will learn:
* What is Back Projection and why it is useful
* How to use the OpenCV function :calc_back_project:`calcBackProject <>` to calculate Back Projection
* How to mix different channels of an image by using the OpenCV function :mix_channels:`mixChannels <>`
......@@ -27,8 +27,8 @@ What is Back Projection?
.. container:: enumeratevisibleitemswithsquare
* Back Projection is a way of recording how well the pixels of a given image fit the distribution of pixels in a histogram model.
* To make it simpler: For Back Projection, you calculate the histogram model of a feature and then use it to find this feature in an image.
* To make it simpler: For Back Projection, you calculate the histogram model of a feature and then use it to find this feature in an image.
* Application example: If you have a histogram of flesh color (say, a Hue-Saturation histogram ), then you can use it to find flesh color areas in an image:
......@@ -42,9 +42,9 @@ How does it work?
* Let's say you have gotten a skin histogram (Hue-Saturation) based on the image below. The histogram besides is going to be our *model histogram* (which we know represents a sample of skin tonality). You applied some mask to capture only the histogram of the skin area:
====== ======
|T0| |T1|
====== ======
====== ======
|T0| |T1|
====== ======
.. |T0| image:: images/Back_Projection_Theory0.jpg
:align: middle
......@@ -55,9 +55,9 @@ How does it work?
* Now, let's imagine that you get another hand image (Test Image) like the one below: (with its respective histogram):
====== ======
|T2| |T3|
====== ======
====== ======
|T2| |T3|
====== ======
.. |T2| image:: images/Back_Projection_Theory2.jpg
:align: middle
......@@ -70,7 +70,7 @@ How does it work?
a. In each pixel of our Test Image (i.e. :math:`p(i,j)` ), collect the data and find the correspondent bin location for that pixel (i.e. :math:`( h_{i,j}, s_{i,j} )` ).
b. Lookup the *model histogram* in the correspondent bin - :math:`( h_{i,j}, s_{i,j} )` - and read the bin value.
b. Lookup the *model histogram* in the correspondent bin - :math:`( h_{i,j}, s_{i,j} )` - and read the bin value.
c. Store this bin value in a new image (*BackProjection*). Also, you may consider to normalize the *model histogram* first, so the output for the Test Image can be visible for you.
......@@ -88,7 +88,7 @@ Code
.. container:: enumeratevisibleitemswithsquare
* **What does this program do?**
.. container:: enumeratevisibleitemswithsquare
* Loads an image
......@@ -99,9 +99,9 @@ Code
* **Downloadable code**:
a. Click `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/Histograms_Matching/calcBackProject_Demo1.cpp>`_ for the basic version (explained in this tutorial).
b. For stuff slightly fancier (using H-S histograms and floodFill to define a mask for the skin area) you can check the `improved demo <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/Histograms_Matching/calcBackProject_Demo2.cpp>`_
c. ...or you can always check out the classical `camshiftdemo <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/camshiftdemo.cpp>`_ in samples.
a. Click `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/Histograms_Matching/calcBackProject_Demo1.cpp>`_ for the basic version (explained in this tutorial).
b. For stuff slightly fancier (using H-S histograms and floodFill to define a mask for the skin area) you can check the `improved demo <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/Histograms_Matching/calcBackProject_Demo2.cpp>`_
c. ...or you can always check out the classical `camshiftdemo <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/camshiftdemo.cpp>`_ in samples.
* **Code at glance:**
......@@ -116,7 +116,7 @@ Code
using namespace std;
/// Global Variables
Mat src; Mat hsv; Mat hue;
Mat src; Mat hsv; Mat hue;
int bins = 25;
/// Function Headers
......@@ -133,7 +133,7 @@ Code
/// Use only the Hue value
hue.create( hsv.size(), hsv.depth() );
int ch[] = { 0, 0 };
mixChannels( &hsv, 1, &hue, 1, ch, 1 );
mixChannels( &hsv, 1, &hue, 1, ch, 1 );
/// Create Trackbar to enter the number of bins
char* window_image = "Source image";
......@@ -146,7 +146,7 @@ Code
/// Wait until user exits the program
waitKey(0);
return 0;
return 0;
}
......@@ -157,7 +157,7 @@ Code
void Hist_and_Backproj(int, void* )
{
MatND hist;
int histSize = MAX( bins, 2 );
int histSize = MAX( bins, 2 );
float hue_range[] = { 0, 180 };
const float* ranges = { hue_range };
......@@ -168,16 +168,16 @@ Code
/// Get Backprojection
MatND backproj;
calcBackProject( &hue, 1, 0, hist, backproj, &ranges, 1, true );
/// Draw the backproj
imshow( "BackProj", backproj );
/// Draw the histogram
int w = 400; int h = 400;
int bin_w = cvRound( (double) w / histSize );
int bin_w = cvRound( (double) w / histSize );
Mat histImg = Mat::zeros( w, h, CV_8UC3 );
for( int i = 0; i < bins; i ++ )
for( int i = 0; i < bins; i ++ )
{ rectangle( histImg, Point( i*bin_w, h ), Point( (i+1)*bin_w, h - cvRound( hist.at<float>(i)*h/255.0 ) ), Scalar( 0, 0, 255 ), -1 ); }
imshow( "Histogram", histImg );
......@@ -190,7 +190,7 @@ Explanation
.. code-block:: cpp
Mat src; Mat hsv; Mat hue;
Mat src; Mat hsv; Mat hue;
int bins = 25;
#. Read the input image and transform it to HSV format:
......@@ -206,7 +206,7 @@ Explanation
hue.create( hsv.size(), hsv.depth() );
int ch[] = { 0, 0 };
mixChannels( &hsv, 1, &hue, 1, ch, 1 );
mixChannels( &hsv, 1, &hue, 1, ch, 1 );
as you see, we use the function :mix_channels:`mixChannels` to get only the channel 0 (Hue) from the hsv image. It gets the following parameters:
......@@ -214,15 +214,15 @@ Explanation
+ **&hsv:** The source array from which the channels will be copied
+ **1:** The number of source arrays
+ **&hue:** The destination array of the copied channels
+ **&hue:** The destination array of the copied channels
+ **1:** The number of destination arrays
+ **ch[] = {0,0}:** The array of index pairs indicating how the channels are copied. In this case, the Hue(0) channel of &hsv is being copied to the 0 channel of &hue (1-channel)
+ **1:** Number of index pairs
+ **1:** Number of index pairs
#. Create a Trackbar for the user to enter the bin values. Any change on the Trackbar means a call to the **Hist_and_Backproj** callback function.
.. code-block:: cpp
char* window_image = "Source image";
namedWindow( window_image, CV_WINDOW_AUTOSIZE );
createTrackbar("* Hue bins: ", window_image, &bins, 180, Hist_and_Backproj );
......@@ -235,7 +235,7 @@ Explanation
imshow( window_image, src );
waitKey(0);
return 0;
return 0;
#. **Hist_and_Backproj function:** Initialize the arguments needed for :calc_hist:`calcHist <>`. The number of bins comes from the Trackbar:
......@@ -245,7 +245,7 @@ Explanation
void Hist_and_Backproj(int, void* )
{
MatND hist;
int histSize = MAX( bins, 2 );
int histSize = MAX( bins, 2 );
float hue_range[] = { 0, 180 };
const float* ranges = { hue_range };
......@@ -264,7 +264,7 @@ Explanation
calcBackProject( &hue, 1, 0, hist, backproj, &ranges, 1, true );
all the arguments are known (the same as used to calculate the histogram), only we add the backproj matrix, which will store the backprojection of the source image (&hue)
#. Display backproj:
.. code-block:: cpp
......@@ -276,10 +276,10 @@ Explanation
.. code-block:: cpp
int w = 400; int h = 400;
int bin_w = cvRound( (double) w / histSize );
int bin_w = cvRound( (double) w / histSize );
Mat histImg = Mat::zeros( w, h, CV_8UC3 );
for( int i = 0; i < bins; i ++ )
for( int i = 0; i < bins; i ++ )
{ rectangle( histImg, Point( i*bin_w, h ), Point( (i+1)*bin_w, h - cvRound( hist.at<float>(i)*h/255.0 ) ), Scalar( 0, 0, 255 ), -1 ); }
imshow( "Histogram", histImg );
......@@ -291,9 +291,9 @@ Results
#. Here are the output by using a sample image ( guess what? Another hand ). You can play with the bin values and you will observe how it affects the results:
====== ====== ======
|R0| |R1| |R2|
====== ====== ======
====== ====== ======
|R0| |R1| |R2|
====== ====== ======
.. |R0| image:: images/Back_Projection1_Source_Image.jpg
:align: middle
......
doc/tutorials/imgproc/histograms/histogram_calculation/histogram_calculation.rst
View file @ ce9b97c7
......@@ -13,7 +13,7 @@ In this tutorial you will learn how to:
* Use the OpenCV function :split:`split <>` to divide an image into its correspondent planes.
* To calculate histograms of arrays of images by using the OpenCV function :calc_hist:`calcHist <>`
* To normalize an array by using the function :normalize:`normalize <>`
......@@ -34,7 +34,7 @@ What are histograms?
.. image:: images/Histogram_Calculation_Theory_Hist0.jpg
:align: center
:align: center
* What happens if we want to *count* this data in an organized way? Since we know that the *range* of information value for this case is 256 values, we can segment our range in subparts (called **bins**) like:
......@@ -42,22 +42,22 @@ What are histograms?
\begin{array}{l}
[0, 255] = { [0, 15] \cup [16, 31] \cup ....\cup [240,255] } \\
range = { bin_{1} \cup bin_{2} \cup ....\cup bin_{n = 15} }
\end{array}
\end{array}
and we can keep count of the number of pixels that fall in the range of each :math:`bin_{i}`. Applying this to the example above we get the image below ( axis x represents the bins and axis y the number of pixels in each of them).
.. image:: images/Histogram_Calculation_Theory_Hist1.jpg
:align: center
:align: center
* This was just a simple example of how an histogram works and why it is useful. An histogram can keep count not only of color intensities, but of whatever image features that we want to measure (i.e. gradients, directions, etc).
* This was just a simple example of how an histogram works and why it is useful. An histogram can keep count not only of color intensities, but of whatever image features that we want to measure (i.e. gradients, directions, etc).
* Let's identify some parts of the histogram:
a. **dims**: The number of parameters you want to collect data of. In our example, **dims = 1** because we are only counting the intensity values of each pixel (in a greyscale image).
b. **bins**: It is the number of **subdivisions** in each dim. In our example, **bins = 16**
c. **range**: The limits for the values to be measured. In this case: **range = [0,255]**
c. **range**: The limits for the values to be measured. In this case: **range = [0,255]**
* What if you want to count two features? In this case your resulting histogram would be a 3D plot (in which x and y would be :math:`bin_{x}` and :math:`bin_{y}` for each feature and z would be the number of counts for each combination of :math:`(bin_{x}, bin_{y})`. The same would apply for more features (of course it gets trickier).
......@@ -65,7 +65,7 @@ What OpenCV offers you
-----------------------
For simple purposes, OpenCV implements the function :calc_hist:`calcHist <>`, which calculates the histogram of a set of arrays (usually images or image planes). It can operate with up to 32 dimensions. We will see it in the code below!
Code
====
......@@ -73,7 +73,7 @@ Code
.. container:: enumeratevisibleitemswithsquare
* **What does this program do?**
.. container:: enumeratevisibleitemswithsquare
* Loads an image
......@@ -82,7 +82,7 @@ Code
* Plot the three histograms in a window
* **Downloadable code**:
Click `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/Histograms_Matching/calcHist_Demo.cpp>`_
Click `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/Histograms_Matching/calcHist_Demo.cpp>`_
* **Code at glance:**
......@@ -181,7 +181,7 @@ Explanation
if( !src.data )
{ return -1; }
#. Separate the source image in its three R,G and B planes. For this we use the OpenCV function :split:`split <>`:
#. Separate the source image in its three R,G and B planes. For this we use the OpenCV function :split:`split <>`:
.. code-block:: cpp
......@@ -195,7 +195,7 @@ Explanation
a. Establish number of bins (5, 10...):
.. code-block:: cpp
int histSize = 256; //from 0 to 255
b. Set the range of values (as we said, between 0 and 255 )
......@@ -219,25 +219,25 @@ Explanation
Mat b_hist, g_hist, r_hist;
e. We proceed to calculate the histograms by using the OpenCV function :calc_hist:`calcHist <>`:
.. code-block:: cpp
/// Compute the histograms:
calcHist( &bgr_planes[0], 1, 0, Mat(), b_hist, 1, &histSize, &histRange, uniform, accumulate );
calcHist( &bgr_planes[1], 1, 0, Mat(), g_hist, 1, &histSize, &histRange, uniform, accumulate );
calcHist( &bgr_planes[2], 1, 0, Mat(), r_hist, 1, &histSize, &histRange, uniform, accumulate );
where the arguments are:
.. container:: enumeratevisibleitemswithsquare
+ **&bgr_planes[0]:** The source array(s)
+ **1**: The number of source arrays (in this case we are using 1. We can enter here also a list of arrays )
+ **0**: The channel (*dim*) to be measured. In this case it is just the intensity (each array is single-channel) so we just write 0.
+ **Mat()**: A mask to be used on the source array ( zeros indicating pixels to be ignored ). If not defined it is not used
+ **b_hist**: The Mat object where the histogram will be stored
+ **1**: The histogram dimensionality.
+ **histSize:** The number of bins per each used dimension
+ **1**: The histogram dimensionality.
+ **histSize:** The number of bins per each used dimension
+ **histRange:** The range of values to be measured per each dimension
+ **uniform** and **accumulate**: The bin sizes are the same and the histogram is cleared at the beginning.
......@@ -264,7 +264,7 @@ Explanation
this function receives these arguments:
.. container:: enumeratevisibleitemswithsquare
+ **b_hist:** Input array
+ **b_hist:** Output normalized array (can be the same)
+ **0** and**histImage.rows**: For this example, they are the lower and upper limits to normalize the values of **r_hist**
......@@ -291,7 +291,7 @@ Explanation
}
we use the expression:
we use the expression:
.. code-block:: cpp
......@@ -315,7 +315,7 @@ Explanation
waitKey(0);
return 0;
Result
======
......@@ -323,10 +323,10 @@ Result
#. Using as input argument an image like the shown below:
.. image:: images/Histogram_Calculation_Original_Image.jpg
:align: center
:align: center
#. Produces the following histogram:
.. image:: images/Histogram_Calculation_Result.jpg
:align: center
:align: center
doc/tutorials/imgproc/histograms/histogram_comparison/histogram_comparison.rst
View file @ ce9b97c7
......@@ -25,43 +25,43 @@ Theory
a. **Correlation ( CV\_COMP\_CORREL )**
.. math::
d(H_1,H_2) = \frac{\sum_I (H_1(I) - \bar{H_1}) (H_2(I) - \bar{H_2})}{\sqrt{\sum_I(H_1(I) - \bar{H_1})^2 \sum_I(H_2(I) - \bar{H_2})^2}}
d(H_1,H_2) = \frac{\sum_I (H_1(I) - \bar{H_1}) (H_2(I) - \bar{H_2})}{\sqrt{\sum_I(H_1(I) - \bar{H_1})^2 \sum_I(H_2(I) - \bar{H_2})^2}}
where
.. math::
\bar{H_k} = \frac{1}{N} \sum _J H_k(J)
\bar{H_k} = \frac{1}{N} \sum _J H_k(J)
and :math:`N` is the total number of histogram bins.
b. **Chi-Square ( CV\_COMP\_CHISQR )**
.. math::
d(H_1,H_2) = \sum _I \frac{\left(H_1(I)-H_2(I)\right)^2}{H_1(I)}
d(H_1,H_2) = \sum _I \frac{\left(H_1(I)-H_2(I)\right)^2}{H_1(I)}
c. **Intersection ( method=CV\_COMP\_INTERSECT )**
.. math::
d(H_1,H_2) = \sum _I \min (H_1(I), H_2(I))
d(H_1,H_2) = \sum _I \min (H_1(I), H_2(I))
d. **Bhattacharyya distance ( CV\_COMP\_BHATTACHARYYA )**
.. math::
d(H_1,H_2) = \sqrt{1 - \frac{1}{\sqrt{\bar{H_1} \bar{H_2} N^2}} \sum_I \sqrt{H_1(I) \cdot H_2(I)}}
d(H_1,H_2) = \sqrt{1 - \frac{1}{\sqrt{\bar{H_1} \bar{H_2} N^2}} \sum_I \sqrt{H_1(I) \cdot H_2(I)}}
Code
====
......@@ -69,7 +69,7 @@ Code
.. container:: enumeratevisibleitemswithsquare
* **What does this program do?**
.. container:: enumeratevisibleitemswithsquare
* Loads a *base image* and 2 *test images* to be compared with it.
......@@ -79,8 +79,8 @@ Code
* Compare the histogram of the *base image* with respect to the 2 test histograms, the histogram of the lower half base image and with the same base image histogram.
* Display the numerical matching parameters obtained.
* **Downloadable code**:
Click `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/Histograms_Matching/compareHist_Demo.cpp>`_
* **Downloadable code**:
Click `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/Histograms_Matching/compareHist_Demo.cpp>`_
* **Code at glance:**
......@@ -105,7 +105,7 @@ Code
/// Load three images with different environment settings
if( argc < 4 )
{ printf("** Error. Usage: ./compareHist_Demo <image_settings0> <image_setting1> <image_settings2>\n");
return -1;
return -1;
}
src_base = imread( argv[1], 1 );
......@@ -117,7 +117,7 @@ Code
cvtColor( src_test1, hsv_test1, CV_BGR2HSV );
cvtColor( src_test2, hsv_test2, CV_BGR2HSV );
hsv_half_down = hsv_base( Range( hsv_base.rows/2, hsv_base.rows - 1 ), Range( 0, hsv_base.cols - 1 ) );
hsv_half_down = hsv_base( Range( hsv_base.rows/2, hsv_base.rows - 1 ), Range( 0, hsv_base.cols - 1 ) );
/// Using 30 bins for hue and 32 for saturation
int h_bins = 50; int s_bins = 60;
......@@ -153,14 +153,14 @@ Code
/// Apply the histogram comparison methods
for( int i = 0; i < 4; i++ )
{ int compare_method = i;
{ int compare_method = i;
double base_base = compareHist( hist_base, hist_base, compare_method );
double base_half = compareHist( hist_base, hist_half_down, compare_method );
double base_test1 = compareHist( hist_base, hist_test1, compare_method );
double base_test2 = compareHist( hist_base, hist_test2, compare_method );
printf( " Method [%d] Perfect, Base-Half, Base-Test(1), Base-Test(2) : %f, %f, %f, %f \n", i, base_base, base_half , base_test1, base_test2 );
}
}
printf( "Done \n" );
......@@ -171,7 +171,7 @@ Code
Explanation
===========
#. Declare variables such as the matrices to store the base image and the two other images to compare ( RGB and HSV )
#. Declare variables such as the matrices to store the base image and the two other images to compare ( RGB and HSV )
.. code-block:: cpp
......@@ -186,7 +186,7 @@ Explanation
if( argc < 4 )
{ printf("** Error. Usage: ./compareHist_Demo <image_settings0> <image_setting1> <image_settings2>\n");
return -1;
return -1;
}
src_base = imread( argv[1], 1 );
......@@ -205,7 +205,7 @@ Explanation
.. code-block:: cpp
hsv_half_down = hsv_base( Range( hsv_base.rows/2, hsv_base.rows - 1 ), Range( 0, hsv_base.cols - 1 ) );
hsv_half_down = hsv_base( Range( hsv_base.rows/2, hsv_base.rows - 1 ), Range( 0, hsv_base.cols - 1 ) );
#. Initialize the arguments to calculate the histograms (bins, ranges and channels H and S ).
......@@ -233,7 +233,7 @@ Explanation
#. Calculate the Histograms for the base image, the 2 test images and the half-down base image:
.. code-block:: cpp
calcHist( &hsv_base, 1, channels, Mat(), hist_base, 2, histSize, ranges, true, false );
normalize( hist_base, hist_base, 0, 1, NORM_MINMAX, -1, Mat() );
......@@ -252,24 +252,24 @@ Explanation
.. code-block:: cpp
for( int i = 0; i < 4; i++ )
{ int compare_method = i;
{ int compare_method = i;
double base_base = compareHist( hist_base, hist_base, compare_method );
double base_half = compareHist( hist_base, hist_half_down, compare_method );
double base_test1 = compareHist( hist_base, hist_test1, compare_method );
double base_test2 = compareHist( hist_base, hist_test2, compare_method );
printf( " Method [%d] Perfect, Base-Half, Base-Test(1), Base-Test(2) : %f, %f, %f, %f \n", i, base_base, base_half , base_test1, base_test2 );
}
}
Results
========
#. We use as input the following images:
============ ============ ============
============ ============ ============
|Base_0| |Test_1| |Test_2|
============ ============ ============
============ ============ ============
.. |Base_0| image:: images/Histogram_Comparison_Source_0.jpg
:align: middle
......@@ -289,10 +289,10 @@ Results
=============== =============== =============== =============== ===============
*Method* Base - Base Base - Half Base - Test 1 Base - Test 2
=============== =============== =============== =============== ===============
*Correlation* 1.000000 0.930766 0.182073 0.120447
*Chi-square* 0.000000 4.940466 21.184536 49.273437
*Intersection* 24.391548 14.959809 3.889029 5.775088
*Bhattacharyya* 0.000000 0.222609 0.646576 0.801869
*Correlation* 1.000000 0.930766 0.182073 0.120447
*Chi-square* 0.000000 4.940466 21.184536 49.273437
*Intersection* 24.391548 14.959809 3.889029 5.775088
*Bhattacharyya* 0.000000 0.222609 0.646576 0.801869
=============== =============== =============== =============== ===============
......
doc/tutorials/imgproc/histograms/histogram_equalization/histogram_equalization.rst
View file @ ce9b97c7
......@@ -12,7 +12,7 @@ In this tutorial you will learn:
* What an image histogram is and why it is useful
* To equalize histograms of images by using the OpenCV function:equalize_hist:`equalizeHist <>`
* To equalize histograms of images by using the OpenCV function:equalize_hist:`equalizeHist <>`
......@@ -24,12 +24,12 @@ What is an Image Histogram?
.. container:: enumeratevisibleitemswithsquare
* It is a graphical representation of the intensity distribution of an image.
* It is a graphical representation of the intensity distribution of an image.
* It quantifies the number of pixels for each intensity value considered.
.. image:: images/Histogram_Equalization_Theory_0.jpg
:align: center
:align: center
What is Histogram Equalization?
......@@ -42,30 +42,30 @@ What is Histogram Equalization?
* To make it clearer, from the image above, you can see that the pixels seem clustered around the middle of the available range of intensities. What Histogram Equalization does is to *stretch out* this range. Take a look at the figure below: The green circles indicate the *underpopulated* intensities. After applying the equalization, we get an histogram like the figure in the center. The resulting image is shown in the picture at right.
.. image:: images/Histogram_Equalization_Theory_1.jpg
:align: center
:align: center
How does it work?
-----------------
.. container:: enumeratevisibleitemswithsquare
* Equalization implies *mapping* one distribution (the given histogram) to another distribution (a wider and more uniform distribution of intensity values) so the intensity values are spreaded over the whole range.
* Equalization implies *mapping* one distribution (the given histogram) to another distribution (a wider and more uniform distribution of intensity values) so the intensity values are spreaded over the whole range.
* To accomplish the equalization effect, the remapping should be the *cumulative distribution function (cdf)* (more details, refer to *Learning OpenCV*). For the histogram :math:`H(i)`, its *cumulative distribution* :math:`H^{'}(i)` is:
.. math::
H^{'}(i) = \sum_{0 \le j < i} H(j)
H^{'}(i) = \sum_{0 \le j < i} H(j)
To use this as a remapping function, we have to normalize :math:`H^{'}(i)` such that the maximum value is 255 ( or the maximum value for the intensity of the image ). From the example above, the cumulative function is:
.. image:: images/Histogram_Equalization_Theory_2.jpg
:align: center
:align: center
* Finally, we use a simple remapping procedure to obtain the intensity values of the equalized image:
.. math::
equalized( x, y ) = H^{'}( src(x,y) )
Code
......@@ -74,16 +74,16 @@ Code
.. container:: enumeratevisibleitemswithsquare
* **What does this program do?**
.. container:: enumeratevisibleitemswithsquare
* Loads an image
* Convert the original image to grayscale
* Convert the original image to grayscale
* Equalize the Histogram by using the OpenCV function :equalize_hist:`EqualizeHist <>`
* Display the source and equalized images in a window.
* **Downloadable code**:
Click `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/Histograms_Matching/EqualizeHist_Demo.cpp>`_
Click `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/Histograms_Matching/EqualizeHist_Demo.cpp>`_
* **Code at glance:**
......@@ -117,15 +117,15 @@ Code
/// Apply Histogram Equalization
equalizeHist( src, dst );
/// Display results
namedWindow( source_window, CV_WINDOW_AUTOSIZE );
namedWindow( equalized_window, CV_WINDOW_AUTOSIZE );
imshow( source_window, src );
imshow( equalized_window, dst );
/// Wait until user exits the program
/// Wait until user exits the program
waitKey(0);
return 0;
......@@ -134,7 +134,7 @@ Code
Explanation
===========
#. Declare the source and destination images as well as the windows names:
#. Declare the source and destination images as well as the windows names:
.. code-block:: cpp
......@@ -144,7 +144,7 @@ Explanation
char* equalized_window = "Equalized Image";
#. Load the source image:
.. code-block:: cpp
src = imread( argv[1], 1 );
......@@ -164,7 +164,7 @@ Explanation
.. code-block:: cpp
equalizeHist( src, dst );
As it can be easily seen, the only arguments are the original image and the output (equalized) image.
#. Display both images (original and equalized) :
......@@ -176,9 +176,9 @@ Explanation
imshow( source_window, src );
imshow( equalized_window, dst );
#. Wait until user exists the program
.. code-block:: cpp
waitKey(0);
......@@ -191,19 +191,19 @@ Results
#. To appreciate better the results of equalization, let's introduce an image with not much contrast, such as:
.. image:: images/Histogram_Equalization_Original_Image.jpg
:align: center
:align: center
which, by the way, has this histogram:
.. image:: images/Histogram_Equalization_Original_Histogram.jpg
:align: center
:align: center
notice that the pixels are clustered around the center of the histogram.
#. After applying the equalization with our program, we get this result:
.. image:: images/Histogram_Equalization_Equalized_Image.jpg
:align: center
:align: center
this image has certainly more contrast. Check out its new histogram like this:
......
doc/tutorials/imgproc/imgtrans/canny_detector/canny_detector.rst
View file @ ce9b97c7
......@@ -19,7 +19,7 @@ Theory
* **Low error rate:** Meaning a good detection of only existent edges.
* **Good localization:** The distance between edge pixels detected and real edge pixels have to be minimized.
* **Minimal response:** Only one detector response per edge.
* **Minimal response:** Only one detector response per edge.
Steps
------
......@@ -27,39 +27,39 @@ Steps
#. Filter out any noise. The Gaussian filter is used for this purpose. An example of a Gaussian kernel of :math:`size = 5` that might be used is shown below:
.. math::
K = \dfrac{1}{159}\begin{bmatrix}
2 & 4 & 5 & 4 & 2 \\
4 & 9 & 12 & 9 & 4 \\
5 & 12 & 15 & 12 & 5 \\
4 & 9 & 12 & 9 & 4 \\
2 & 4 & 5 & 4 & 2
\end{bmatrix}
2 & 4 & 5 & 4 & 2
\end{bmatrix}
#. Find the intensity gradient of the image. For this, we follow a procedure analogous to Sobel:
#. Find the intensity gradient of the image. For this, we follow a procedure analogous to Sobel:
a. Apply a pair of convolution masks (in :math:`x` and :math:`y` directions:
.. math::
G_{x} = \begin{bmatrix}
-1 & 0 & +1 \\
-2 & 0 & +2 \\
-1 & 0 & +1
-1 & 0 & +1
\end{bmatrix}
G_{y} = \begin{bmatrix}
-1 & -2 & -1 \\
0 & 0 & 0 \\
+1 & +2 & +1
\end{bmatrix}
+1 & +2 & +1
\end{bmatrix}
b. Find the gradient strength and direction with:
.. math::
\begin{array}{l}
G = \sqrt{ G_{x}^{2} + G_{y}^{2} } \\
G = \sqrt{ G_{x}^{2} + G_{y}^{2} } \\
\theta = \arctan(\dfrac{ G_{y} }{ G_{x} })
\end{array}
......@@ -71,22 +71,22 @@ Steps
a. If a pixel gradient is higher than the *upper* threshold, the pixel is accepted as an edge
b. If a pixel gradient value is below the *lower* threshold, then it is rejected.
c. If the pixel gradient is between the two thresholds, then it will be accepted only if it is connected to a pixel that is above the *upper* threshold.
c. If the pixel gradient is between the two thresholds, then it will be accepted only if it is connected to a pixel that is above the *upper* threshold.
Canny recommended a *upper*:*lower* ratio between 2:1 and 3:1.
#. For more details, you can always consult your favorite Computer Vision book.
#. For more details, you can always consult your favorite Computer Vision book.
Code
=====
#. **What does this program do?**
* Asks the user to enter a numerical value to set the lower threshold for our *Canny Edge Detector* (by means of a Trackbar)
* Applies the *Canny Detector* and generates a **mask** (bright lines representing the edges on a black background).
* Applies the mask obtained on the original image and display it in a window.
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/CannyDetector_Demo.cpp>`_
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgTrans/CannyDetector_Demo.cpp>`_
.. code-block:: cpp
......@@ -123,7 +123,7 @@ Code
/// Using Canny's output as a mask, we display our result
dst = Scalar::all(0);
src.copyTo( dst, detected_edges);
imshow( window_name, dst );
}
......@@ -194,7 +194,7 @@ Explanation
{ return -1; }
#. Create a matrix of the same type and size of *src* (to be *dst*)
.. code-block:: cpp
dst.create( src.size(), src.type() );
......@@ -249,9 +249,9 @@ Explanation
.. code-block:: cpp
dst = Scalar::all(0);
#. Finally, we will use the function :copy_to:`copyTo <>` to map only the areas of the image that are identified as edges (on a black background).
#. Finally, we will use the function :copy_to:`copyTo <>` to map only the areas of the image that are identified as edges (on a black background).
.. code-block:: cpp
src.copyTo( dst, detected_edges);
......@@ -280,8 +280,8 @@ Result
:alt: Result after running Canny
:width: 200pt
:align: center
* Notice how the image is superposed to the black background on the edge regions.
doc/tutorials/imgproc/imgtrans/copyMakeBorder/copyMakeBorder.rst
View file @ ce9b97c7
......@@ -10,8 +10,8 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV function :copy_make_border:`copyMakeBorder <>` to set the borders (extra padding to your image).
* Use the OpenCV function :copy_make_border:`copyMakeBorder <>` to set the borders (extra padding to your image).
Theory
========
......@@ -19,14 +19,14 @@ Theory
The explanation below belongs to the book **Learning OpenCV** by Bradski and Kaehler.
#. In our previous tutorial we learned to use convolution to operate on images. One problem that naturally arises is how to handle the boundaries. How can we convolve them if the evaluated points are at the edge of the image?
#. In our previous tutorial we learned to use convolution to operate on images. One problem that naturally arises is how to handle the boundaries. How can we convolve them if the evaluated points are at the edge of the image?
#. What most of OpenCV functions do is to copy a given image onto another slightly larger image and then automatically pads the boundary (by any of the methods explained in the sample code just below). This way, the convolution can be performed over the needed pixels without problems (the extra padding is cut after the operation is done).
#. In this tutorial, we will briefly explore two ways of defining the extra padding (border) for an image:
a. **BORDER_CONSTANT**: Pad the image with a constant value (i.e. black or :math:`0`
b. **BORDER_REPLICATE**: The row or column at the very edge of the original is replicated to the extra border.
This will be seen more clearly in the Code section.
......@@ -37,20 +37,20 @@ Code
======
#. **What does this program do?**
* Load an image
* Load an image
* Let the user choose what kind of padding use in the input image. There are two options:
#. *Constant value border*: Applies a padding of a constant value for the whole border. This value will be updated randomly each 0.5 seconds.
#. *Constant value border*: Applies a padding of a constant value for the whole border. This value will be updated randomly each 0.5 seconds.
#. *Replicated border*: The border will be replicated from the pixel values at the edges of the original image.
The user chooses either option by pressing 'c' (constant) or 'r' (replicate)
* The program finishes when the user presses 'ESC'
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/copyMakeBorder_demo.cpp>`_
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgTrans/copyMakeBorder_demo.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
......@@ -59,7 +59,7 @@ Code
using namespace cv;
/// Global Variables
/// Global Variables
Mat src, dst;
int top, bottom, left, right;
int borderType;
......@@ -75,10 +75,10 @@ Code
/// Load an image
src = imread( argv[1] );
if( !src.data )
{ return -1;
printf(" No data entered, please enter the path to an image file \n");
printf(" No data entered, please enter the path to an image file \n");
}
/// Brief how-to for this program
......@@ -92,12 +92,12 @@ Code
namedWindow( window_name, CV_WINDOW_AUTOSIZE );
/// Initialize arguments for the filter
top = (int) (0.05*src.rows); bottom = (int) (0.05*src.rows);
top = (int) (0.05*src.rows); bottom = (int) (0.05*src.rows);
left = (int) (0.05*src.cols); right = (int) (0.05*src.cols);
dst = src;
imshow( window_name, dst );
while( true )
{
c = waitKey(500);
......@@ -140,14 +140,14 @@ Explanation
.. code-block:: cpp
src = imread( argv[1] );
if( !src.data )
{ return -1;
printf(" No data entered, please enter the path to an image file \n");
printf(" No data entered, please enter the path to an image file \n");
}
#. After giving a short intro of how to use the program, we create a window:
.. code-block:: cpp
namedWindow( window_name, CV_WINDOW_AUTOSIZE );
......@@ -156,13 +156,13 @@ Explanation
.. code-block:: cpp
top = (int) (0.05*src.rows); bottom = (int) (0.05*src.rows);
top = (int) (0.05*src.rows); bottom = (int) (0.05*src.rows);
left = (int) (0.05*src.cols); right = (int) (0.05*src.cols);
#. The program begins a *while* loop. If the user presses 'c' or 'r', the *borderType* variable takes the value of *BORDER_CONSTANT* or *BORDER_REPLICATE* respectively:
.. code-block:: cpp
while( true )
{
c = waitKey(500);
......@@ -185,7 +185,7 @@ Explanation
#. Finally, we call the function :copy_make_border:`copyMakeBorder <>` to apply the respective padding:
.. code-block:: cpp
copyMakeBorder( src, dst, top, bottom, left, right, borderType, value );
The arguments are:
......@@ -199,7 +199,7 @@ Explanation
#. We display our output image in the image created previously
.. code-block:: cpp
imshow( window_name, dst );
......@@ -213,12 +213,12 @@ Results
.. container:: enumeratevisibleitemswithsquare
* By default, it begins with the border set to BORDER_CONSTANT. Hence, a succession of random colored borders will be shown.
* If you press 'r', the border will become a replica of the edge pixels.
* If you press 'r', the border will become a replica of the edge pixels.
* If you press 'c', the random colored borders will appear again
* If you press 'ESC' the program will exit.
Below some screenshot showing how the border changes color and how the *BORDER_REPLICATE* option looks:
.. image:: images/CopyMakeBorder_Tutorial_Results.jpg
:alt: Final result after copyMakeBorder application
......
doc/tutorials/imgproc/imgtrans/filter_2d/filter_2d.rst
View file @ ce9b97c7
......@@ -10,8 +10,8 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV function :filter2d:`filter2D <>` to create your own linear filters.
* Use the OpenCV function :filter2d:`filter2D <>` to create your own linear filters.
Theory
=======
......@@ -21,15 +21,15 @@ Theory
Convolution
------------
In a very general sense, convolution is an operation between every part of an image and an operator (kernel).
In a very general sense, convolution is an operation between every part of an image and an operator (kernel).
What is a kernel?
------------------
A kernel is essentially a fixed size array of numerical coefficeints along with an *anchor point* in that array, which is tipically located at the center.
A kernel is essentially a fixed size array of numerical coefficeints along with an *anchor point* in that array, which is tipically located at the center.
.. image:: images/filter_2d_tutorial_kernel_theory.png
:alt: kernel example
:align: center
:align: center
How does convolution with a kernel work?
-----------------------------------------
......@@ -38,7 +38,7 @@ Assume you want to know the resulting value of a particular location in the imag
#. Place the kernel anchor on top of a determined pixel, with the rest of the kernel overlaying the corresponding local pixels in the image.
#. Multiply the kernel coefficients by the corresponding image pixel values and sum the result.
#. Multiply the kernel coefficients by the corresponding image pixel values and sum the result.
#. Place the result to the location of the *anchor* in the input image.
......@@ -47,35 +47,35 @@ Assume you want to know the resulting value of a particular location in the imag
Expressing the procedure above in the form of an equation we would have:
.. math::
H(x,y) = \sum_{i=0}^{M_{i} - 1} \sum_{j=0}^{M_{j}-1} I(x+i - a_{i}, y + j - a_{j})K(i,j)
Fortunately, OpenCV provides you with the function :filter2d:`filter2D <>` so you do not have to code all these operations.
Fortunately, OpenCV provides you with the function :filter2d:`filter2D <>` so you do not have to code all these operations.
Code
======
#. **What does this program do?**
* Loads an image
* Performs a *normalized box filter*. For instance, for a kernel of size :math:`size = 3`, the kernel would be:
.. math::
K = \dfrac{1}{3 \cdot 3} \begin{bmatrix}
1 & 1 & 1 \\
1 & 1 & 1 \\
1 & 1 & 1
\end{bmatrix}
1 & 1 & 1
\end{bmatrix}
The program will perform the filter operation with kernels of sizes 3, 5, 7, 9 and 11.
* The filter output (with each kernel) will be shown during 500 milliseconds
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/filter2D_demo.cpp>`_
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgTrans/filter2D_demo.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
......@@ -93,7 +93,7 @@ Code
Mat kernel;
Point anchor;
double delta;
int ddepth;
int ddepth;
int kernel_size;
char* window_name = "filter2D Demo";
......@@ -107,7 +107,7 @@ Code
/// Create window
namedWindow( window_name, CV_WINDOW_AUTOSIZE );
/// Initialize arguments for the filter
anchor = Point( -1, -1 );
delta = 0;
......@@ -131,7 +131,7 @@ Code
imshow( window_name, dst );
ind++;
}
return 0;
}
......@@ -171,12 +171,12 @@ Explanation
kernel_size = 3 + 2*( ind%5 );
kernel = Mat::ones( kernel_size, kernel_size, CV_32F )/ (float)(kernel_size*kernel_size);
The first line is to update the *kernel_size* to odd values in the range: :math:`[3,11]`. The second line actually builds the kernel by setting its value to a matrix filled with :math:`1's` and normalizing it by dividing it between the number of elements.
The first line is to update the *kernel_size* to odd values in the range: :math:`[3,11]`. The second line actually builds the kernel by setting its value to a matrix filled with :math:`1's` and normalizing it by dividing it between the number of elements.
#. After setting the kernel, we can generate the filter by using the function :filter2d:`filter2D <>`:
.. code-block:: cpp
filter2D(src, dst, ddepth , kernel, anchor, delta, BORDER_DEFAULT );
The arguments denote:
......
doc/tutorials/imgproc/imgtrans/hough_circle/hough_circle.rst
View file @ ce9b97c7
......@@ -17,16 +17,16 @@ Hough Circle Transform
* The Hough Circle Transform works in a *roughly* analogous way to the Hough Line Transform explained in the previous tutorial.
* In the line detection case, a line was defined by two parameters :math:`(r, \theta)`. In the circle case, we need three parameters to define a circle:
.. math::
C : ( x_{center}, y_{center}, r )
C : ( x_{center}, y_{center}, r )
where :math:`(x_{center}, y_{center})` define the center position (gree point) and :math:`r` is the radius, which allows us to completely define a circle, as it can be seen below:
.. image:: images/Hough_Circle_Tutorial_Theory_0.jpg
:alt: Result of detecting circles with Hough Transform
:align: center
:align: center
* For sake of efficiency, OpenCV implements a detection method slightly trickier than the standard Hough Transform: *The Hough gradient method*. For more details, please check the book *Learning OpenCV* or your favorite Computer Vision bibliography
......@@ -34,19 +34,19 @@ Code
======
#. **What does this program do?**
* Loads an image and blur it to reduce the noise
* Applies the *Hough Circle Transform* to the blurred image .
* Applies the *Hough Circle Transform* to the blurred image .
* Display the detected circle in a window.
.. |TutorialHoughCirclesSimpleDownload| replace:: here
.. _TutorialHoughCirclesSimpleDownload: http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/houghlines.cpp
.. _TutorialHoughCirclesSimpleDownload: http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/houghlines.cpp
.. |TutorialHoughCirclesFancyDownload| replace:: here
.. _TutorialHoughCirclesFancyDownload: http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/HoughCircle_Demo.cpp
.. _TutorialHoughCirclesFancyDownload: http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgTrans/HoughCircle_Demo.cpp
#. The sample code that we will explain can be downloaded from |TutorialHoughCirclesSimpleDownload|_. A slightly fancier version (which shows both Hough standard and probabilistic with trackbars for changing the threshold values) can be found |TutorialHoughCirclesFancyDownload|_.
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
......@@ -66,7 +66,7 @@ Code
if( !src.data )
{ return -1; }
/// Convert it to gray
/// Convert it to gray
cvtColor( src, src_gray, CV_BGR2GRAY );
/// Reduce the noise so we avoid false circle detection
......@@ -88,7 +88,7 @@ Code
circle( src, center, radius, Scalar(0,0,255), 3, 8, 0 );
}
/// Show your results
/// Show your results
namedWindow( "Hough Circle Transform Demo", CV_WINDOW_AUTOSIZE );
imshow( "Hough Circle Transform Demo", src );
......@@ -117,7 +117,7 @@ Explanation
cvtColor( src, src_gray, CV_BGR2GRAY );
#. Apply a Gaussian blur to reduce noise and avoid false circle detection:
.. code-block:: cpp
GaussianBlur( src_gray, src_gray, Size(9, 9), 2, 2 );
......@@ -138,10 +138,10 @@ Explanation
* *dp = 1*: The inverse ratio of resolution
* *min_dist = src_gray.rows/8*: Minimum distance between detected centers
* *param_1 = 200*: Upper threshold for the internal Canny edge detector
* *param_2* = 100*: Threshold for center detection.
* *min_radius = 0*: Minimum radio to be detected. If unknown, put zero as default.
* *param_2* = 100*: Threshold for center detection.
* *min_radius = 0*: Minimum radio to be detected. If unknown, put zero as default.
* *max_radius = 0*: Maximum radius to be detected. If unknown, put zero as default
#. Draw the detected circles:
.. code-block:: cpp
......@@ -154,14 +154,14 @@ Explanation
circle( src, center, 3, Scalar(0,255,0), -1, 8, 0 );
// circle outline
circle( src, center, radius, Scalar(0,0,255), 3, 8, 0 );
}
}
You can see that we will draw the circle(s) on red and the center(s) with a small green dot
#. Display the detected circle(s):
.. code-block:: cpp
namedWindow( "Hough Circle Transform Demo", CV_WINDOW_AUTOSIZE );
imshow( "Hough Circle Transform Demo", src );
......@@ -175,8 +175,8 @@ Explanation
Result
=======
The result of running the code above with a test image is shown below:
The result of running the code above with a test image is shown below:
.. image:: images/Hough_Circle_Tutorial_Result.jpg
:alt: Result of detecting circles with Hough Transform
:align: center
:align: center
doc/tutorials/imgproc/imgtrans/hough_lines/hough_lines.rst
View file @ ce9b97c7
......@@ -9,7 +9,7 @@ Goal
In this tutorial you will learn how to:
* Use the OpenCV functions :hough_lines:`HoughLines <>` and :hough_lines_p:`HoughLinesP <>` to detect lines in an image.
Theory
=======
......@@ -18,60 +18,60 @@ Theory
Hough Line Transform
---------------------
#. The Hough Line Transform is a transform used to detect straight lines.
#. The Hough Line Transform is a transform used to detect straight lines.
#. To apply the Transform, first an edge detection pre-processing is desirable.
How does it work?
^^^^^^^^^^^^^^^^^^
#. As you know, a line in the image space can be expressed with two variables. For example:
a. In the **Cartesian coordinate system:** Parameters: :math:`(m,b)`.
b. In the **Polar coordinate system:** Parameters: :math:`(r,\theta)`
.. image:: images/Hough_Lines_Tutorial_Theory_0.jpg
:alt: Line variables
:align: center
:align: center
For Hough Transforms, we will express lines in the *Polar system*. Hence, a line equation can be written as:
For Hough Transforms, we will express lines in the *Polar system*. Hence, a line equation can be written as:
.. math::
y = \left ( -\dfrac{\cos \theta}{\sin \theta} \right ) x + \left ( \dfrac{r}{\sin \theta} \right )
y = \left ( -\dfrac{\cos \theta}{\sin \theta} \right ) x + \left ( \dfrac{r}{\sin \theta} \right )
Arranging the terms: :math:`r = x \cos \theta + y \sin \theta`
#. In general for each point :math:`(x_{0}, y_{0})`, we can define the family of lines that goes through that point as:
.. math::
r_{\theta} = x_{0} \cdot \cos \theta + y_{0} \cdot \sin \theta
Meaning that each pair :math:`(r_{\theta},\theta)` represents each line that passes by :math:`(x_{0}, y_{0})`.
Meaning that each pair :math:`(r_{\theta},\theta)` represents each line that passes by :math:`(x_{0}, y_{0})`.
#. If for a given :math:`(x_{0}, y_{0})` we plot the family of lines that goes through it, we get a sinusoid. For instance, for :math:`x_{0} = 8` and :math:`y_{0} = 6` we get the following plot (in a plane :math:`\theta` - :math:`r`):
.. image:: images/Hough_Lines_Tutorial_Theory_1.jpg
:alt: Polar plot of a the family of lines of a point
:align: center
:align: center
We consider only points such that :math:`r > 0` and :math:`0< \theta < 2 \pi`.
We consider only points such that :math:`r > 0` and :math:`0< \theta < 2 \pi`.
#. We can do the same operation above for all the points in an image. If the curves of two different points intersect in the plane :math:`\theta` - :math:`r`, that means that both points belong to a same line. For instance, following with the example above and drawing the plot for two more points: :math:`x_{1} = 9`, :math:`y_{1} = 4` and :math:`x_{2} = 12`, :math:`y_{2} = 3`, we get:
.. image:: images/Hough_Lines_Tutorial_Theory_2.jpg
:alt: Polar plot of the family of lines for three points
:align: center
:align: center
The three plots intersect in one single point :math:`(0.925, 9.6)`, these coordinates are the parameters (:math:`\theta, r`) or the line in which :math:`(x_{0}, y_{0})`, :math:`(x_{1}, y_{1})` and :math:`(x_{2}, y_{2})` lay.
The three plots intersect in one single point :math:`(0.925, 9.6)`, these coordinates are the parameters (:math:`\theta, r`) or the line in which :math:`(x_{0}, y_{0})`, :math:`(x_{1}, y_{1})` and :math:`(x_{2}, y_{2})` lay.
#. What does all the stuff above mean? It means that in general, a line can be *detected* by finding the number of intersections between curves.The more curves intersecting means that the line represented by that intersection have more points. In general, we can define a *threshold* of the minimum number of intersections needed to *detect* a line.
#. This is what the Hough Line Transform does. It keeps track of the intersection between curves of every point in the image. If the number of intersections is above some *threshold*, then it declares it as a line with the parameters :math:`(\theta, r_{\theta})` of the intersection point.
Standard and Probabilistic Hough Line Transform
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
OpenCV implements two kind of Hough Line Transforms:
OpenCV implements two kind of Hough Line Transforms:
a. **The Standard Hough Transform**
......@@ -88,21 +88,21 @@ b. **The Probabilistic Hough Line Transform**
Code
======
.. |TutorialHoughLinesSimpleDownload| replace:: here
.. _TutorialHoughLinesSimpleDownload: http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/houghlines.cpp
.. |TutorialHoughLinesFancyDownload| replace:: here
.. _TutorialHoughLinesFancyDownload: http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/HoughLines_Demo.cpp
.. |TutorialHoughLinesSimpleDownload| replace:: here
.. _TutorialHoughLinesSimpleDownload: http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/houghlines.cpp
.. |TutorialHoughLinesFancyDownload| replace:: here
.. _TutorialHoughLinesFancyDownload: http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgTrans/HoughLines_Demo.cpp
#. **What does this program do?**
* Loads an image
* Applies either a *Standard Hough Line Transform* or a *Probabilistic Line Transform*.
* Applies either a *Standard Hough Line Transform* or a *Probabilistic Line Transform*.
* Display the original image and the detected line in two windows.
#. The sample code that we will explain can be downloaded from |TutorialHoughLinesSimpleDownload|_. A slightly fancier version (which shows both Hough standard and probabilistic with trackbars for changing the threshold values) can be found |TutorialHoughLinesFancyDownload|_.
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
......@@ -207,9 +207,9 @@ Explanation
* *rho* : The resolution of the parameter :math:`r` in pixels. We use **1** pixel.
* *theta*: The resolution of the parameter :math:`\theta` in radians. We use **1 degree** (CV_PI/180)
* *threshold*: The minimum number of intersections to "*detect*" a line
* *srn* and *stn*: Default parameters to zero. Check OpenCV reference for more info.
* *srn* and *stn*: Default parameters to zero. Check OpenCV reference for more info.
b. And then you display the result by drawing the lines.
b. And then you display the result by drawing the lines.
.. code-block:: cpp
......@@ -236,14 +236,14 @@ Explanation
HoughLinesP(dst, lines, 1, CV_PI/180, 50, 50, 10 );
with the arguments:
* *dst*: Output of the edge detector. It should be a grayscale image (although in fact it is a binary one)
* *lines*: A vector that will store the parameters :math:`(x_{start}, y_{start}, x_{end}, y_{end})` of the detected lines
* *rho* : The resolution of the parameter :math:`r` in pixels. We use **1** pixel.
* *theta*: The resolution of the parameter :math:`\theta` in radians. We use **1 degree** (CV_PI/180)
* *threshold*: The minimum number of intersections to "*detect*" a line
* *minLinLength*: The minimum number of points that can form a line. Lines with less than this number of points are disregarded.
* *maxLineGap*: The maximum gap between two points to be considered in the same line.
* *minLinLength*: The minimum number of points that can form a line. Lines with less than this number of points are disregarded.
* *maxLineGap*: The maximum gap between two points to be considered in the same line.
b. And then you display the result by drawing the lines.
......@@ -256,7 +256,7 @@ Explanation
}
#. Display the original image and the detected lines:
#. Display the original image and the detected lines:
.. code-block:: cpp
......@@ -274,20 +274,20 @@ Result
=======
.. note::
The results below are obtained using the slightly fancier version we mentioned in the *Code* section. It still implements the same stuff as above, only adding the Trackbar for the Threshold.
Using an input image such as:
.. image:: images/Hough_Lines_Tutorial_Original_Image.jpg
:alt: Result of detecting lines with Hough Transform
:align: center
:align: center
We get the following result by using the Probabilistic Hough Line Transform:
.. image:: images/Hough_Lines_Tutorial_Result.jpg
:alt: Result of detecting lines with Hough Transform
:align: center
:align: center
You may observe that the number of lines detected vary while you change the *threshold*. The explanation is sort of evident: If you establish a higher threshold, fewer lines will be detected (since you will need more points to declare a line detected).
You may observe that the number of lines detected vary while you change the *threshold*. The explanation is sort of evident: If you establish a higher threshold, fewer lines will be detected (since you will need more points to declare a line detected).
doc/tutorials/imgproc/imgtrans/laplace_operator/laplace_operator.rst
View file @ ce9b97c7
......@@ -36,7 +36,7 @@ Laplacian Operator
-------------------
#. From the explanation above, we deduce that the second derivative can be used to *detect edges*. Since images are "*2D*", we would need to take the derivative in both dimensions. Here, the Laplacian operator comes handy.
#. The *Laplacian operator* is defined by:
.. math::
......@@ -49,13 +49,13 @@ Code
======
#. **What does this program do?**
* Loads an image
* Remove noise by applying a Gaussian blur and then convert the original image to grayscale
* Remove noise by applying a Gaussian blur and then convert the original image to grayscale
* Applies a Laplacian operator to the grayscale image and stores the output image
* Display the result in a window
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/Laplace_Demo.cpp>`_
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgTrans/Laplace_Demo.cpp>`_
.. code-block:: cpp
......@@ -70,7 +70,7 @@ Code
int main( int argc, char** argv )
{
Mat src, src_gray, dst;
int kernel_size = 3;
int kernel_size = 3;
int scale = 1;
int delta = 0;
int ddepth = CV_16S;
......@@ -116,7 +116,7 @@ Explanation
.. code-block:: cpp
Mat src, src_gray, dst;
int kernel_size = 3;
int kernel_size = 3;
int scale = 1;
int delta = 0;
int ddepth = CV_16S;
......@@ -136,7 +136,7 @@ Explanation
.. code-block:: cpp
GaussianBlur( src, src, Size(3,3), 0, 0, BORDER_DEFAULT );
#. Convert the image to grayscale using :cvt_color:`cvtColor <>`
.. code-block:: cpp
......
doc/tutorials/imgproc/imgtrans/remap/remap.rst
View file @ ce9b97c7
......@@ -16,14 +16,14 @@ Theory
What is remapping?
------------------
* It is the process of taking pixels from one place in the image and locating them in another position in a new image.
* It is the process of taking pixels from one place in the image and locating them in another position in a new image.
* To accomplish the mapping process, it might be necessary to do some interpolation for non-integer pixel locations, since there will not always be a one-to-one-pixel correspondence between source and destination images.
* We can express the remap for every pixel location :math:`(x,y)` as:
.. math::
g(x,y) = f ( h(x,y) )
where :math:`g()` is the remapped image, :math:`f()` the source image and :math:`h(x,y)` is the mapping function that operates on :math:`(x,y)`.
......@@ -34,7 +34,7 @@ What is remapping?
h(x,y) = (I.cols - x, y )
What would happen? It is easily seen that the image would flip in the :math:`x` direction. For instance, consider the input image:
What would happen? It is easily seen that the image would flip in the :math:`x` direction. For instance, consider the input image:
.. image:: images/Remap_Tutorial_Theory_0.jpg
:alt: Original test image
......@@ -54,12 +54,12 @@ Code
====
#. **What does this program do?**
* Loads an image
* Each second, apply 1 of 4 different remapping processes to the image and display them indefinitely in a window.
* Wait for the user to exit the program
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/Remap_Demo.cpp>`_
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgTrans/Remap_Demo.cpp>`_
.. code-block:: cpp
......@@ -91,7 +91,7 @@ Code
dst.create( src.size(), src.type() );
map_x.create( src.size(), CV_32FC1 );
map_y.create( src.size(), CV_32FC1 );
/// Create window
namedWindow( remap_window, CV_WINDOW_AUTOSIZE );
......@@ -106,7 +106,7 @@ Code
/// Update map_x & map_y. Then apply remap
update_map();
remap( src, dst, map_x, map_y, CV_INTER_LINEAR, BORDER_CONSTANT, Scalar(0,0, 0) );
remap( src, dst, map_x, map_y, CV_INTER_LINEAR, BORDER_CONSTANT, Scalar(0,0, 0) );
/// Display results
imshow( remap_window, dst );
......@@ -126,7 +126,7 @@ Code
{ for( int i = 0; i < src.cols; i++ )
{
switch( ind )
{
{
case 0:
if( i > src.cols*0.25 && i < src.cols*0.75 && j > src.rows*0.25 && j < src.rows*0.75 )
{
......@@ -169,7 +169,7 @@ Explanation
int ind = 0;
#. Load an image:
.. code-block:: cpp
src = imread( argv[1], 1 );
......@@ -181,7 +181,7 @@ Explanation
dst.create( src.size(), src.type() );
map_x.create( src.size(), CV_32FC1 );
map_y.create( src.size(), CV_32FC1 );
#. Create a window to display results
.. code-block:: cpp
......@@ -189,7 +189,7 @@ Explanation
namedWindow( remap_window, CV_WINDOW_AUTOSIZE );
#. Establish a loop. Each 1000 ms we update our mapping matrices (*mat_x* and *mat_y*) and apply them to our source image:
.. code-block:: cpp
while( true )
......@@ -202,19 +202,19 @@ Explanation
/// Update map_x & map_y. Then apply remap
update_map();
remap( src, dst, map_x, map_y, CV_INTER_LINEAR, BORDER_CONSTANT, Scalar(0,0, 0) );
remap( src, dst, map_x, map_y, CV_INTER_LINEAR, BORDER_CONSTANT, Scalar(0,0, 0) );
/// Display results
imshow( remap_window, dst );
}
The function that applies the remapping is :remap:`remap <>`. We give the following arguments:
* **src**: Source image
* **dst**: Destination image of same size as *src*
* **map_x**: The mapping function in the x direction. It is equivalent to the first component of :math:`h(i,j)`
* **map_y**: Same as above, but in y direction. Note that *map_y* and *map_x* are both of the same size as *src*
* **CV_INTER_LINEAR**: The type of interpolation to use for non-integer pixels. This is by default.
* **CV_INTER_LINEAR**: The type of interpolation to use for non-integer pixels. This is by default.
* **BORDER_CONSTANT**: Default
How do we update our mapping matrices *mat_x* and *mat_y*? Go on reading:
......@@ -225,25 +225,25 @@ Explanation
.. math::
h(i,j) = ( 2*i - src.cols/2 + 0.5, 2*j - src.rows/2 + 0.5)
h(i,j) = ( 2*i - src.cols/2 + 0.5, 2*j - src.rows/2 + 0.5)
for all pairs :math:`(i,j)` such that: :math:`\dfrac{src.cols}{4}<i<\dfrac{3 \cdot src.cols}{4}` and :math:`\dfrac{src.rows}{4}<j<\dfrac{3 \cdot src.rows}{4}`
for all pairs :math:`(i,j)` such that: :math:`\dfrac{src.cols}{4}<i<\dfrac{3 \cdot src.cols}{4}` and :math:`\dfrac{src.rows}{4}<j<\dfrac{3 \cdot src.rows}{4}`
b. Turn the image upside down: :math:`h( i, j ) = (i, src.rows - j)`
c. Reflect the image from left to right: :math:`h(i,j) = ( src.cols - i, j )`
d. Combination of b and c: :math:`h(i,j) = ( src.cols - i, src.rows - j )`
This is expressed in the following snippet. Here, *map_x* represents the first coordinate of *h(i,j)* and *map_y* the second coordinate.
.. code-block:: cpp
for( int j = 0; j < src.rows; j++ )
{ for( int i = 0; i < src.cols; i++ )
{
switch( ind )
{
{
case 0:
if( i > src.cols*0.25 && i < src.cols*0.75 && j > src.rows*0.25 && j < src.rows*0.75 )
{
......@@ -292,7 +292,7 @@ Result
:align: center
#. Turning it upside down:
.. image:: images/Remap_Tutorial_Result_1.jpg
:alt: Result 0 for remapping
:width: 250pt
......
doc/tutorials/imgproc/imgtrans/sobel_derivatives/sobel_derivatives.rst
View file @ ce9b97c7
......@@ -12,8 +12,8 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV function :sobel:`Sobel <>` to calculate the derivatives from an image.
* Use the OpenCV function :scharr:`Scharr <>` to calculate a more accurate derivative for a kernel of size :math:`3 \cdot 3`
* Use the OpenCV function :scharr:`Scharr <>` to calculate a more accurate derivative for a kernel of size :math:`3 \cdot 3`
Theory
========
......@@ -29,8 +29,8 @@ Theory
.. image:: images/Sobel_Derivatives_Tutorial_Theory_0.jpg
:alt: How intensity changes in an edge
:align: center
You can easily notice that in an *edge*, the pixel intensity *changes* in a notorious way. A good way to express *changes* is by using *derivatives*. A high change in gradient indicates a major change in the image.
You can easily notice that in an *edge*, the pixel intensity *changes* in a notorious way. A good way to express *changes* is by using *derivatives*. A high change in gradient indicates a major change in the image.
#. To be more graphical, let's assume we have a 1D-image. An edge is shown by the "jump" in intensity in the plot below:
......@@ -51,9 +51,9 @@ Theory
Sobel Operator
---------------
#. The Sobel Operator is a discrete differentiation operator. It computes an approximation of the gradient of an image intensity function.
#. The Sobel Operator is a discrete differentiation operator. It computes an approximation of the gradient of an image intensity function.
#. The Sobel Operator combines Gaussian smoothing and differentiation.
#. The Sobel Operator combines Gaussian smoothing and differentiation.
Formulation
^^^^^^^^^^^^
......@@ -64,21 +64,21 @@ Assuming that the image to be operated is :math:`I`:
a. **Horizontal changes**: This is computed by convolving :math:`I` with a kernel :math:`G_{x}` with odd size. For example for a kernel size of 3, :math:`G_{x}` would be computed as:
.. math::
G_{x} = \begin{bmatrix}
-1 & 0 & +1 \\
-2 & 0 & +2 \\
-1 & 0 & +1
-1 & 0 & +1
\end{bmatrix} * I
b. **Vertical changes**: This is computed by convolving :math:`I` with a kernel :math:`G_{y}` with odd size. For example for a kernel size of 3, :math:`G_{y}` would be computed as:
.. math::
G_{y} = \begin{bmatrix}
-1 & -2 & -1 \\
0 & 0 & 0 \\
+1 & +2 & +1
+1 & +2 & +1
\end{bmatrix} * I
#. At each point of the image we calculate an approximation of the *gradient* in that point by combining both results above:
......@@ -90,7 +90,7 @@ Assuming that the image to be operated is :math:`I`:
Although sometimes the following simpler equation is used:
.. math::
G = |G_{x}| + |G_{y}|
......@@ -103,14 +103,14 @@ Assuming that the image to be operated is :math:`I`:
G_{x} = \begin{bmatrix}
-3 & 0 & +3 \\
-10 & 0 & +10 \\
-3 & 0 & +3
\end{bmatrix}
-3 & 0 & +3
\end{bmatrix}
G_{y} = \begin{bmatrix}
-3 & -10 & -3 \\
0 & 0 & 0 \\
+3 & +10 & +3
\end{bmatrix}
+3 & +10 & +3
\end{bmatrix}
You can check out more information of this function in the OpenCV reference (:scharr:`Scharr <>`). Also, in the sample code below, you will notice that above the code for :sobel:`Sobel <>` function there is also code for the :scharr:`Scharr <>` function commented. Uncommenting it (and obviously commenting the Sobel stuff) should give you an idea of how this function works.
......@@ -118,12 +118,12 @@ Code
=====
#. **What does this program do?**
* Applies the *Sobel Operator* and generates as output an image with the detected *edges* bright on a darker background.
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/Sobel_Demo.cpp>`_
.. code-block:: cpp
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgTrans/Sobel_Demo.cpp>`_
.. code-block:: cpp
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
......@@ -137,7 +137,7 @@ Code
{
Mat src, src_gray;
Mat grad;
Mat grad;
char* window_name = "Sobel Demo - Simple Edge Detector";
int scale = 1;
int delta = 0;
......@@ -162,15 +162,15 @@ Code
/// Generate grad_x and grad_y
Mat grad_x, grad_y;
Mat abs_grad_x, abs_grad_y;
/// Gradient X
//Scharr( src_gray, grad_x, ddepth, 1, 0, scale, delta, BORDER_DEFAULT );
Sobel( src_gray, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT );
Sobel( src_gray, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_x, abs_grad_x );
/// Gradient Y
/// Gradient Y
//Scharr( src_gray, grad_y, ddepth, 0, 1, scale, delta, BORDER_DEFAULT );
Sobel( src_gray, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT );
Sobel( src_gray, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT );
convertScaleAbs( grad_y, abs_grad_y );
/// Total Gradient (approximate)
......@@ -192,7 +192,7 @@ Explanation
.. code-block:: cpp
Mat src, src_gray;
Mat grad;
Mat grad;
char* window_name = "Sobel Demo - Simple Edge Detector";
int scale = 1;
int delta = 0;
......@@ -203,12 +203,12 @@ Explanation
.. code-block:: cpp
src = imread( argv[1] );
if( !src.data )
{ return -1; }
#. First, we apply a :gaussian_blur:`GaussianBlur <>` to our image to reduce the noise ( kernel size = 3 )
.. code-block:: cpp
GaussianBlur( src, src, Size(3,3), 0, 0, BORDER_DEFAULT );
......@@ -220,27 +220,27 @@ Explanation
cvtColor( src, src_gray, CV_RGB2GRAY );
#. Second, we calculate the "*derivatives*" in *x* and *y* directions. For this, we use the function :sobel:`Sobel <>` as shown below:
.. code-block:: cpp
Mat grad_x, grad_y;
Mat abs_grad_x, abs_grad_y;
/// Gradient X
Sobel( src_gray, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT );
/// Gradient Y
Sobel( src_gray, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT );
Sobel( src_gray, grad_x, ddepth, 1, 0, 3, scale, delta, BORDER_DEFAULT );
/// Gradient Y
Sobel( src_gray, grad_y, ddepth, 0, 1, 3, scale, delta, BORDER_DEFAULT );
The function takes the following arguments:
* *src_gray*: In our example, the input image. Here it is *CV_8U*
* *grad_x*/*grad_y*: The output image.
* *src_gray*: In our example, the input image. Here it is *CV_8U*
* *grad_x*/*grad_y*: The output image.
* *ddepth*: The depth of the output image. We set it to *CV_16S* to avoid overflow.
* *x_order*: The order of the derivative in **x** direction.
* *y_order*: The order of the derivative in **y** direction.
* *x_order*: The order of the derivative in **x** direction.
* *y_order*: The order of the derivative in **y** direction.
* *scale*, *delta* and *BORDER_DEFAULT*: We use default values.
Notice that to calculate the gradient in *x* direction we use: :math:`x_{order}= 1` and :math:`y_{order} = 0`. We do analogously for the *y* direction.
Notice that to calculate the gradient in *x* direction we use: :math:`x_{order}= 1` and :math:`y_{order} = 0`. We do analogously for the *y* direction.
#. We convert our partial results back to *CV_8U*:
......@@ -248,7 +248,7 @@ Explanation
convertScaleAbs( grad_x, abs_grad_x );
convertScaleAbs( grad_y, abs_grad_y );
#. Finally, we try to approximate the *gradient* by adding both directional gradients (note that this is not an exact calculation at all! but it is good for our purposes).
......@@ -268,7 +268,7 @@ Results
========
#. Here is the output of applying our basic detector to *lena.jpg*:
.. image:: images/Sobel_Derivatives_Tutorial_Result.jpg
:alt: Result of applying Sobel operator to lena.jpg
......
doc/tutorials/imgproc/imgtrans/warp_affine/warp_affine.rst
View file @ ce9b97c7
......@@ -19,49 +19,49 @@ Theory
What is an Affine Transformation?
----------------------------------
#. It is any transformation that can be expressed in the form of a *matrix multiplication* (linear transformation) followed by a *vector addition* (translation).
#. It is any transformation that can be expressed in the form of a *matrix multiplication* (linear transformation) followed by a *vector addition* (translation).
#. From the above, We can use an Affine Transformation to express:
#. From the above, We can use an Affine Transformation to express:
a. Rotations (linear transformation)
b. Translations (vector addition)
c. Scale operations (linear transformation)
you can see that, in essence, an Affine Transformation represents a **relation** between two images.
#. The usual way to represent an Affine Transform is by using a :math:`2 \times 3` matrix.
you can see that, in essence, an Affine Transformation represents a **relation** between two images.
.. math::
#. The usual way to represent an Affine Transform is by using a :math:`2 \times 3` matrix.
.. math::
A = \begin{bmatrix}
a_{00} & a_{01} \\
a_{00} & a_{01} \\
a_{10} & a_{11}
\end{bmatrix}_{2 \times 2}
B = \begin{bmatrix}
b_{00} \\
b_{00} \\
b_{10}
\end{bmatrix}_{2 \times 1}
M = \begin{bmatrix}
A & B
A & B
\end{bmatrix}
=
=
\begin{bmatrix}
a_{00} & a_{01} & b_{00} \\
a_{10} & a_{11} & b_{10}
a_{00} & a_{01} & b_{00} \\
a_{10} & a_{11} & b_{10}
\end{bmatrix}_{2 \times 3}
Considering that we want to transform a 2D vector :math:`X = \begin{bmatrix}x \\ y\end{bmatrix}` by using :math:`A` and :math:`B`, we can do it equivalently with:
:math:`T = A \cdot \begin{bmatrix}x \\ y\end{bmatrix} + B` or :math:`T = M \cdot [x, y, 1]^{T}`
.. math::
T = \begin{bmatrix}
a_{00}x + a_{01}y + b_{00} \\
a_{00}x + a_{01}y + b_{00} \\
a_{10}x + a_{11}y + b_{10}
\end{bmatrix}
\end{bmatrix}
How do we get an Affine Transformation?
......@@ -80,20 +80,20 @@ How do we get an Affine Transformation?
:width: 350pt
:align: center
the points 1, 2 and 3 (forming a triangle in image 1) are mapped into image 2, still forming a triangle, but now they have changed notoriously. If we find the Affine Transformation with these 3 points (you can choose them as you like), then we can apply this found relation to the whole pixels in the image.
the points 1, 2 and 3 (forming a triangle in image 1) are mapped into image 2, still forming a triangle, but now they have changed notoriously. If we find the Affine Transformation with these 3 points (you can choose them as you like), then we can apply this found relation to the whole pixels in the image.
Code
====
#. **What does this program do?**
* Loads an image
* Applies an Affine Transform to the image. This Transform is obtained from the relation between three points. We use the function :warp_affine:`warpAffine <>` for that purpose.
* Applies a Rotation to the image after being transformed. This rotation is with respect to the image center
* Waits until the user exits the program
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgTrans/Geometric_Transforms_Demo.cpp>`_
#. The tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgTrans/Geometric_Transforms_Demo.cpp>`_
.. code-block:: cpp
......@@ -123,14 +123,14 @@ Code
/// Load the image
src = imread( argv[1], 1 );
/// Set the dst image the same type and size as src
/// Set the dst image the same type and size as src
warp_dst = Mat::zeros( src.rows, src.cols, src.type() );
/// Set your 3 points to calculate the Affine Transform
srcTri[0] = Point2f( 0,0 );
srcTri[1] = Point2f( src.cols - 1, 0 );
srcTri[2] = Point2f( 0, src.rows - 1 );
dstTri[0] = Point2f( src.cols*0.0, src.rows*0.33 );
dstTri[1] = Point2f( src.cols*0.85, src.rows*0.25 );
dstTri[2] = Point2f( src.cols*0.15, src.rows*0.7 );
......@@ -153,7 +153,7 @@ Code
/// Rotate the warped image
warpAffine( warp_dst, warp_rotate_dst, rot_mat, warp_dst.size() );
/// Show what you got
namedWindow( source_window, CV_WINDOW_AUTOSIZE );
imshow( source_window, src );
......@@ -193,7 +193,7 @@ Explanation
#. Initialize the destination image as having the same size and type as the source:
.. code-block:: cpp
warp_dst = Mat::zeros( src.rows, src.cols, src.type() );
#. **Affine Transform:** As we explained lines above, we need two sets of 3 points to derive the affine transform relation. Take a look:
......@@ -203,11 +203,11 @@ Explanation
srcTri[0] = Point2f( 0,0 );
srcTri[1] = Point2f( src.cols - 1, 0 );
srcTri[2] = Point2f( 0, src.rows - 1 );
dstTri[0] = Point2f( src.cols*0.0, src.rows*0.33 );
dstTri[1] = Point2f( src.cols*0.85, src.rows*0.25 );
dstTri[2] = Point2f( src.cols*0.15, src.rows*0.7 );
You may want to draw the points to make a better idea of how they change. Their locations are approximately the same as the ones depicted in the example figure (in the Theory section). You may note that the size and orientation of the triangle defined by the 3 points change.
#. Armed with both sets of points, we calculate the Affine Transform by using OpenCV function :get_affine_transform:`getAffineTransform <>`:
......@@ -264,7 +264,7 @@ Explanation
#. Finally, we display our results in two windows plus the original image for good measure:
.. code-block:: cpp
namedWindow( source_window, CV_WINDOW_AUTOSIZE );
imshow( source_window, src );
......@@ -292,7 +292,7 @@ Result
:alt: Original image
:width: 250pt
:align: center
after applying the first Affine Transform we obtain:
.. image:: images/Warp_Affine_Tutorial_Result_Warp.jpg
......
doc/tutorials/imgproc/opening_closing_hats/opening_closing_hats.rst
View file @ ce9b97c7
......@@ -11,8 +11,8 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV function :morphology_ex:`morphologyEx <>` to apply Morphological Transformation such as:
+ Opening
+ Opening
+ Closing
+ Morphological Gradient
+ Top Hat
......@@ -24,12 +24,12 @@ Theory
.. note::
The explanation below belongs to the book **Learning OpenCV** by Bradski and Kaehler.
In the previous tutorial we covered two basic Morphology operations:
In the previous tutorial we covered two basic Morphology operations:
.. container:: enumeratevisibleitemswithsquare
* Erosion
* Dilation.
* Dilation.
Based on these two we can effectuate more sophisticated transformations to our images. Here we discuss briefly 05 operations offered by OpenCV:
......@@ -39,7 +39,7 @@ Opening
* It is obtained by the erosion of an image followed by a dilation.
.. math::
dst = open( src, element) = dilate( erode( src, element ) )
* Useful for removing small objects (it is assumed that the objects are bright on a dark foreground)
......@@ -48,7 +48,7 @@ Opening
.. image:: images/Morphology_2_Tutorial_Theory_Opening.png
:alt: Opening
:align: center
:align: center
Closing
---------
......@@ -56,14 +56,14 @@ Closing
* It is obtained by the dilation of an image followed by an erosion.
.. math::
dst = close( src, element ) = erode( dilate( src, element ) )
* Useful to remove small holes (dark regions).
* Useful to remove small holes (dark regions).
.. image:: images/Morphology_2_Tutorial_Theory_Closing.png
:alt: Closing example
:align: center
:align: center
Morphological Gradient
......@@ -79,7 +79,7 @@ Morphological Gradient
.. image:: images/Morphology_2_Tutorial_Theory_Gradient.png
:alt: Gradient
:align: center
:align: center
Top Hat
......@@ -88,12 +88,12 @@ Top Hat
* It is the difference between an input image and its opening.
.. math::
dst = tophat( src, element ) = src - open( src, element )
.. image:: images/Morphology_2_Tutorial_Theory_TopHat.png
:alt: Top Hat
:align: center
:align: center
Black Hat
----------
......@@ -101,19 +101,19 @@ Black Hat
* It is the difference between the closing and its input image
.. math::
dst = blackhat( src, element ) = close( src, element ) - src
.. image:: images/Morphology_2_Tutorial_Theory_BlackHat.png
:alt: Black Hat
:align: center
:align: center
Code
======
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgProc/Morphology_2.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgProc/Morphology_2.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
......@@ -145,7 +145,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
if( !src.data )
{ return -1; }
/// Create window
namedWindow( window_name, CV_WINDOW_AUTOSIZE );
......@@ -153,12 +153,12 @@ This tutorial code's is shown lines below. You can also download it from `here <
createTrackbar("Operator:\n 0: Opening - 1: Closing \n 2: Gradient - 3: Top Hat \n 4: Black Hat", window_name, &morph_operator, max_operator, Morphology_Operations );
/// Create Trackbar to select kernel type
createTrackbar( "Element:\n 0: Rect - 1: Cross - 2: Ellipse", window_name,
&morph_elem, max_elem,
createTrackbar( "Element:\n 0: Rect - 1: Cross - 2: Ellipse", window_name,
&morph_elem, max_elem,
Morphology_Operations );
/// Create Trackbar to choose kernel size
createTrackbar( "Kernel size:\n 2n +1", window_name,
createTrackbar( "Kernel size:\n 2n +1", window_name,
&morph_size, max_kernel_size,
Morphology_Operations );
......@@ -169,7 +169,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
return 0;
}
/**
/**
* @function Morphology_Operations
*/
void Morphology_Operations( int, void* )
......@@ -177,11 +177,11 @@ This tutorial code's is shown lines below. You can also download it from `here <
// Since MORPH_X : 2,3,4,5 and 6
int operation = morph_operator + 2;
Mat element = getStructuringElement( morph_elem, Size( 2*morph_size + 1, 2*morph_size+1 ), Point( morph_size, morph_size ) );
Mat element = getStructuringElement( morph_elem, Size( 2*morph_size + 1, 2*morph_size+1 ), Point( morph_size, morph_size ) );
/// Apply the specified morphology operation
morphologyEx( src, dst, operation, element );
imshow( window_name, dst );
imshow( window_name, dst );
}
......@@ -200,34 +200,34 @@ Explanation
.. code-block:: cpp
createTrackbar("Operator:\n 0: Opening - 1: Closing \n 2: Gradient - 3: Top Hat \n 4: Black Hat",
window_name, &morph_operator, max_operator,
createTrackbar("Operator:\n 0: Opening - 1: Closing \n 2: Gradient - 3: Top Hat \n 4: Black Hat",
window_name, &morph_operator, max_operator,
Morphology_Operations );
* The second trackbar **"Element"** returns **morph_elem**, which indicates what kind of structure our kernel is:
* The second trackbar **"Element"** returns **morph_elem**, which indicates what kind of structure our kernel is:
.. code-block:: cpp
createTrackbar( "Element:\n 0: Rect - 1: Cross - 2: Ellipse", window_name,
&morph_elem, max_elem,
createTrackbar( "Element:\n 0: Rect - 1: Cross - 2: Ellipse", window_name,
&morph_elem, max_elem,
Morphology_Operations );
* The final trackbar **"Kernel Size"** returns the size of the kernel to be used (**morph_size**)
.. code-block:: cpp
createTrackbar( "Kernel size:\n 2n +1", window_name,
createTrackbar( "Kernel size:\n 2n +1", window_name,
&morph_size, max_kernel_size,
Morphology_Operations );
* Every time we move any slider, the user's function **Morphology_Operations** will be called to effectuate a new morphology operation and it will update the output image based on the current trackbar values.
.. code-block:: cpp
/**
/**
* @function Morphology_Operations
*/
void Morphology_Operations( int, void* )
......@@ -235,11 +235,11 @@ Explanation
// Since MORPH_X : 2,3,4,5 and 6
int operation = morph_operator + 2;
Mat element = getStructuringElement( morph_elem, Size( 2*morph_size + 1, 2*morph_size+1 ), Point( morph_size, morph_size ) );
Mat element = getStructuringElement( morph_elem, Size( 2*morph_size + 1, 2*morph_size+1 ), Point( morph_size, morph_size ) );
/// Apply the specified morphology operation
morphologyEx( src, dst, operation, element );
imshow( window_name, dst );
imshow( window_name, dst );
}
......@@ -259,11 +259,11 @@ Explanation
.. code-block:: cpp
int operation = morph_operator + 2;
int operation = morph_operator + 2;
* **element**: The kernel to be used. We use the function :get_structuring_element:`getStructuringElement <>` to define our own structure.
Results
========
......@@ -272,11 +272,11 @@ Results
.. image:: images/Morphology_2_Tutorial_Original_Image.jpg
:alt: Morphology 2: Original image
:align: center
:align: center
* And here are two snapshots of the display window. The first picture shows the output after using the operator **Opening** with a cross kernel. The second picture (right side, shows the result of using a **Blackhat** operator with an ellipse kernel.
.. image:: images/Morphology_2_Tutorial_Cover.jpg
:alt: Morphology 2: Result sample
:align: center
:align: center
doc/tutorials/imgproc/pyramids/pyramids.rst
View file @ ce9b97c7
......@@ -11,7 +11,7 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV functions :pyr_up:`pyrUp <>` and :pyr_down:`pyrDown <>` to downsample or upsample a given image.
Theory
=======
......@@ -21,9 +21,9 @@ Theory
.. container:: enumeratevisibleitemswithsquare
* Usually we need to convert an image to a size different than its original. For this, there are two possible options:
#. *Upsize* the image (zoom in) or
#. *Downsize* it (zoom out).
#. *Upsize* the image (zoom in) or
#. *Downsize* it (zoom out).
* Although there is a *geometric transformation* function in OpenCV that -literally- resize an image (:resize:`resize <>`, which we will show in a future tutorial), in this section we analyze first the use of **Image Pyramids**, which are widely applied in a huge range of vision applications.
......@@ -39,20 +39,20 @@ Image Pyramid
* **Gaussian pyramid:** Used to downsample images
* **Laplacian pyramid:** Used to reconstruct an upsampled image from an image lower in the pyramid (with less resolution)
* **Laplacian pyramid:** Used to reconstruct an upsampled image from an image lower in the pyramid (with less resolution)
* In this tutorial we'll use the *Gaussian pyramid*.
Gaussian Pyramid
^^^^^^^^^^^^^^^^^
* Imagine the pyramid as a set of layers in which the higher the layer, the smaller the size.
* Imagine the pyramid as a set of layers in which the higher the layer, the smaller the size.
.. image:: images/Pyramids_Tutorial_Pyramid_Theory.png
:alt: Pyramid figure
:align: center
:align: center
* Every layer is numbered from bottom to top, so layer :math:`(i+1)` (denoted as :math:`G_{i+1}` is smaller than layer :math:`i` (:math:`G_{i}`).
* Every layer is numbered from bottom to top, so layer :math:`(i+1)` (denoted as :math:`G_{i+1}` is smaller than layer :math:`i` (:math:`G_{i}`).
* To produce layer :math:`(i+1)` in the Gaussian pyramid, we do the following:
......@@ -60,9 +60,9 @@ Gaussian Pyramid
.. math::
\frac{1}{16} \begin{bmatrix} 1 & 4 & 6 & 4 & 1 \\ 4 & 16 & 24 & 16 & 4 \\ 6 & 24 & 36 & 24 & 6 \\ 4 & 16 & 24 & 16 & 4 \\ 1 & 4 & 6 & 4 & 1 \end{bmatrix}
\frac{1}{16} \begin{bmatrix} 1 & 4 & 6 & 4 & 1 \\ 4 & 16 & 24 & 16 & 4 \\ 6 & 24 & 36 & 24 & 6 \\ 4 & 16 & 24 & 16 & 4 \\ 1 & 4 & 6 & 4 & 1 \end{bmatrix}
* Remove every even-numbered row and column.
* Remove every even-numbered row and column.
* You can easily notice that the resulting image will be exactly one-quarter the area of its predecessor. Iterating this process on the input image :math:`G_{0}` (original image) produces the entire pyramid.
......@@ -72,7 +72,7 @@ Gaussian Pyramid
* Perform a convolution with the same kernel shown above (multiplied by 4) to approximate the values of the "missing pixels"
* These two procedures (downsampling and upsampling as explained above) are implemented by the OpenCV functions :pyr_up:`pyrUp <>` and :pyr_down:`pyrDown <>`, as we will see in an example with the code below:
* These two procedures (downsampling and upsampling as explained above) are implemented by the OpenCV functions :pyr_up:`pyrUp <>` and :pyr_down:`pyrDown <>`, as we will see in an example with the code below:
.. note::
When we reduce the size of an image, we are actually *losing* information of the image.
......@@ -80,9 +80,9 @@ Gaussian Pyramid
Code
======
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ImgProc/Pyramids.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ImgProc/Pyramids.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/imgproc/imgproc.hpp"
#include "opencv2/highgui/highgui.hpp"
......@@ -115,7 +115,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
{ printf(" No data! -- Exiting the program \n");
return -1; }
tmp = src;
tmp = src;
dst = tmp;
/// Create window
......@@ -124,7 +124,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
/// Loop
while( true )
{
{
int c;
c = waitKey(10);
......@@ -132,7 +132,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
{ break; }
if( (char)c == 'u' )
{ pyrUp( tmp, dst, Size( tmp.cols*2, tmp.rows*2 ) );
printf( "** Zoom In: Image x 2 \n" );
printf( "** Zoom In: Image x 2 \n" );
}
else if( (char)c == 'd' )
{ pyrDown( tmp, dst, Size( tmp.cols/2, tmp.rows/2 ) );
......@@ -141,7 +141,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
imshow( window_name, dst );
tmp = dst;
}
}
return 0;
}
......@@ -160,13 +160,13 @@ Explanation
{ printf(" No data! -- Exiting the program \n");
return -1; }
* Create a Mat object to store the result of the operations (*dst*) and one to save temporal results (*tmp*).
* Create a Mat object to store the result of the operations (*dst*) and one to save temporal results (*tmp*).
.. code-block:: cpp
Mat src, dst, tmp;
/* ... */
tmp = src;
tmp = src;
dst = tmp;
......@@ -183,7 +183,7 @@ Explanation
.. code-block:: cpp
while( true )
{
{
int c;
c = waitKey(10);
......@@ -191,7 +191,7 @@ Explanation
{ break; }
if( (char)c == 'u' )
{ pyrUp( tmp, dst, Size( tmp.cols*2, tmp.rows*2 ) );
printf( "** Zoom In: Image x 2 \n" );
printf( "** Zoom In: Image x 2 \n" );
}
else if( (char)c == 'd' )
{ pyrDown( tmp, dst, Size( tmp.cols/2, tmp.rows/2 ) );
......@@ -200,12 +200,12 @@ Explanation
imshow( window_name, dst );
tmp = dst;
}
}
Our program exits if the user presses *ESC*. Besides, it has two options:
* **Perform upsampling (after pressing 'u')**
* **Perform upsampling (after pressing 'u')**
.. code-block:: cpp
......@@ -217,7 +217,7 @@ Explanation
* *dst*: The destination image (to be shown on screen, supposedly the double of the input image)
* *Size( tmp.cols*2, tmp.rows*2 )* : The destination size. Since we are upsampling, :pyr_up:`pyrUp <>` expects a size double than the input image (in this case *tmp*).
* **Perform downsampling (after pressing 'd')**
* **Perform downsampling (after pressing 'd')**
.. code-block:: cpp
......@@ -232,7 +232,7 @@ Explanation
* Notice that it is important that the input image can be divided by a factor of two (in both dimensions). Otherwise, an error will be shown.
* Finally, we update the input image **tmp** with the current image displayed, so the subsequent operations are performed on it.
.. code-block:: cpp
tmp = dst;
......@@ -245,19 +245,19 @@ Results
* After compiling the code above we can test it. The program calls an image **chicky_512.jpg** that comes in the *tutorial_code/image* folder. Notice that this image is :math:`512 \times 512`, hence a downsample won't generate any error (:math:`512 = 2^{9}`). The original image is shown below:
.. image:: images/Pyramids_Tutorial_Original_Image.jpg
:alt: Pyramids: Original image
:align: center
:alt: Pyramids: Original image
:align: center
* First we apply two successive :pyr_down:`pyrDown <>` operations by pressing 'd'. Our output is:
.. image:: images/Pyramids_Tutorial_PyrDown_Result.jpg
:alt: Pyramids: PyrDown Result
:align: center
:align: center
* Note that we should have lost some resolution due to the fact that we are diminishing the size of the image. This is evident after we apply :pyr_up:`pyrUp <>` twice (by pressing 'u'). Our output is now:
.. image:: images/Pyramids_Tutorial_PyrUp_Result.jpg
:alt: Pyramids: PyrUp Result
:align: center
:align: center
doc/tutorials/imgproc/shapedescriptors/bounding_rects_circles/bounding_rects_circles.rst
View file @ ce9b97c7
......@@ -11,9 +11,9 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV function :bounding_rect:`boundingRect <>`
* Use the OpenCV function :bounding_rect:`boundingRect <>`
* Use the OpenCV function :min_enclosing_circle:`minEnclosingCircle <>`
Theory
======
......@@ -21,9 +21,9 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ShapeDescriptors/generalContours_demo1.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ShapeDescriptors/generalContours_demo1.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
......@@ -73,7 +73,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
/// Detect edges using Threshold
threshold( src_gray, threshold_output, thresh, 255, THRESH_BINARY );
/// Find contours
/// Find contours
findContours( threshold_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
/// Approximate contours to polygons + get bounding rects and circles
......@@ -83,18 +83,18 @@ This tutorial code's is shown lines below. You can also download it from `here <
vector<float>radius( contours.size() );
for( int i = 0; i < contours.size(); i++ )
{ approxPolyDP( Mat(contours[i]), contours_poly[i], 3, true );
boundRect[i] = boundingRect( Mat(contours_poly[i]) );
{ approxPolyDP( Mat(contours[i]), contours_poly[i], 3, true );
boundRect[i] = boundingRect( Mat(contours_poly[i]) );
minEnclosingCircle( contours_poly[i], center[i], radius[i] );
}
}
/// Draw polygonal contour + bonding rects + circles
Mat drawing = Mat::zeros( threshold_output.size(), CV_8UC3 );
for( int i = 0; i< contours.size(); i++ )
{
{
Scalar color = Scalar( rng.uniform(0, 255), rng.uniform(0,255), rng.uniform(0,255) );
drawContours( drawing, contours_poly, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
drawContours( drawing, contours_poly, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
rectangle( drawing, boundRect[i].tl(), boundRect[i].br(), color, 2, 8, 0 );
circle( drawing, center[i], (int)radius[i], color, 2, 8, 0 );
}
......@@ -112,13 +112,13 @@ Result
#. Here it is:
========== ==========
|BRC_0| |BRC_1|
========== ==========
========== ==========
|BRC_0| |BRC_1|
========== ==========
.. |BRC_0| image:: images/Bounding_Rects_Circles_Source_Image.jpg
:align: middle
.. |BRC_1| image:: images/Bounding_Rects_Circles_Result.jpg
:align: middle
:align: middle
doc/tutorials/imgproc/shapedescriptors/bounding_rotated_ellipses/bounding_rotated_ellipses.rst
View file @ ce9b97c7
......@@ -11,9 +11,9 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV function :min_area_rect:`minAreaRect <>`
* Use the OpenCV function :min_area_rect:`minAreaRect <>`
* Use the OpenCV function :fit_ellipse:`fitEllipse <>`
Theory
======
......@@ -21,9 +21,9 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ShapeDescriptors/generalContours_demo2.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ShapeDescriptors/generalContours_demo2.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
......@@ -73,7 +73,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
/// Detect edges using Threshold
threshold( src_gray, threshold_output, thresh, 255, THRESH_BINARY );
/// Find contours
/// Find contours
findContours( threshold_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
/// Find the rotated rectangles and ellipses for each contour
......@@ -81,29 +81,29 @@ This tutorial code's is shown lines below. You can also download it from `here <
vector<RotatedRect> minEllipse( contours.size() );
for( int i = 0; i < contours.size(); i++ )
{ minRect[i] = minAreaRect( Mat(contours[i]) );
{ minRect[i] = minAreaRect( Mat(contours[i]) );
if( contours[i].size() > 5 )
{ minEllipse[i] = fitEllipse( Mat(contours[i]) ); }
}
}
/// Draw contours + rotated rects + ellipses
Mat drawing = Mat::zeros( threshold_output.size(), CV_8UC3 );
for( int i = 0; i< contours.size(); i++ )
{
{
Scalar color = Scalar( rng.uniform(0, 255), rng.uniform(0,255), rng.uniform(0,255) );
// contour
drawContours( drawing, contours, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
drawContours( drawing, contours, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
// ellipse
ellipse( drawing, minEllipse[i], color, 2, 8 );
// rotated rectangle
// rotated rectangle
Point2f rect_points[4]; minRect[i].points( rect_points );
for( int j = 0; j < 4; j++ )
line( drawing, rect_points[j], rect_points[(j+1)%4], color, 1, 8 );
line( drawing, rect_points[j], rect_points[(j+1)%4], color, 1, 8 );
}
/// Show in a window
namedWindow( "Contours", CV_WINDOW_AUTOSIZE );
imshow( "Contours", drawing );
imshow( "Contours", drawing );
}
Explanation
......@@ -114,13 +114,13 @@ Result
#. Here it is:
========== ==========
|BRE_0| |BRE_1|
========== ==========
========== ==========
|BRE_0| |BRE_1|
========== ==========
.. |BRE_0| image:: images/Bounding_Rotated_Ellipses_Source_Image.jpg
:align: middle
.. |BRE_1| image:: images/Bounding_Rotated_Ellipses_Result.jpg
:align: middle
:align: middle
doc/tutorials/imgproc/shapedescriptors/find_contours/find_contours.rst
View file @ ce9b97c7
......@@ -10,8 +10,8 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV function :find_contours:`findContours <>`
* Use the OpenCV function :draw_contours:`drawContours <>`
* Use the OpenCV function :find_contours:`findContours <>`
* Use the OpenCV function :draw_contours:`drawContours <>`
Theory
======
......@@ -19,9 +19,9 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ShapeDescriptors/findContours_demo.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ShapeDescriptors/findContours_demo.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
......@@ -71,20 +71,20 @@ This tutorial code's is shown lines below. You can also download it from `here <
/// Detect edges using canny
Canny( src_gray, canny_output, thresh, thresh*2, 3 );
/// Find contours
/// Find contours
findContours( canny_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
/// Draw contours
Mat drawing = Mat::zeros( canny_output.size(), CV_8UC3 );
for( int i = 0; i< contours.size(); i++ )
{
{
Scalar color = Scalar( rng.uniform(0, 255), rng.uniform(0,255), rng.uniform(0,255) );
drawContours( drawing, contours, i, color, 2, 8, hierarchy, 0, Point() );
drawContours( drawing, contours, i, color, 2, 8, hierarchy, 0, Point() );
}
/// Show in a window
namedWindow( "Contours", CV_WINDOW_AUTOSIZE );
imshow( "Contours", drawing );
imshow( "Contours", drawing );
}
Explanation
......@@ -95,13 +95,13 @@ Result
#. Here it is:
============= =============
|contour_0| |contour_1|
============= =============
============= =============
|contour_0| |contour_1|
============= =============
.. |contour_0| image:: images/Find_Contours_Original_Image.jpg
:align: middle
.. |contour_1| image:: images/Find_Contours_Result.jpg
:align: middle
:align: middle
doc/tutorials/imgproc/shapedescriptors/hull/hull.rst
View file @ ce9b97c7
......@@ -10,7 +10,7 @@ In this tutorial you will learn how to:
.. container:: enumeratevisibleitemswithsquare
* Use the OpenCV function :convex_hull:`convexHull <>`
* Use the OpenCV function :convex_hull:`convexHull <>`
Theory
......@@ -19,11 +19,11 @@ Theory
Code
====
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/svn/opencv/trunk/opencv/samples/cpp/tutorial_code/ShapeDescriptors/hull_demo.cpp>`_
This tutorial code's is shown lines below. You can also download it from `here <http://code.opencv.org/projects/opencv/repository/revisions/master/raw/samples/cpp/tutorial_code/ShapeDescriptors/hull_demo.cpp>`_
.. code-block:: cpp
.. code-block:: cpp
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/imgproc/imgproc.hpp"
#include <iostream>
#include <stdio.h>
......@@ -33,7 +33,7 @@ This tutorial code's is shown lines below. You can also download it from `here <
using namespace std;
Mat src; Mat src_gray;
int thresh = 100;
int thresh = 100;
int max_thresh = 255;
RNG rng(12345);
......@@ -73,21 +73,21 @@ This tutorial code's is shown lines below. You can also download it from `here <
/// Detect edges using Threshold
threshold( src_gray, threshold_output, thresh, 255, THRESH_BINARY );
/// Find contours
/// Find contours
findContours( threshold_output, contours, hierarchy, CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE, Point(0, 0) );
/// Find the convex hull object for each contour
vector<vector<Point> >hull( contours.size() );
for( int i = 0; i < contours.size(); i++ )
{ convexHull( Mat(contours[i]), hull[i], false ); }
{ convexHull( Mat(contours[i]), hull[i], false ); }
/// Draw contours + hull results
Mat drawing = Mat::zeros( threshold_output.size(), CV_8UC3 );
for( int i = 0; i< contours.size(); i++ )
{
{
Scalar color = Scalar( rng.uniform(0, 255), rng.uniform(0,255), rng.uniform(0,255) );
drawContours( drawing, contours, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
drawContours( drawing, hull, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
drawContours( drawing, contours, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
drawContours( drawing, hull, i, color, 1, 8, vector<Vec4i>(), 0, Point() );
}
/// Show in a window
......@@ -104,13 +104,13 @@ Result
#. Here it is:
========== ==========
|Hull_0| |Hull_1|
========== ==========
========== ==========
|Hull_0| |Hull_1|
========== ==========
.. |Hull_0| image:: images/Hull_Original_Image.jpg
:align: middle
.. |Hull_1| image:: images/Hull_Result.jpg
:align: middle
:align: middle
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