Merge pull request #10232 from TomBecker-BD:hough-many-circles

Hough many circles (#10232)

* Add Hui's optimization. Merge with latest changes in OpenCV.

* Use conditional compilation instead of a runtime flag.

* Whitespace.

* Create the sequence for the nonzero edge pixels only if using that approach.

* Improve performance for finding very large numbers of circles

* Return the circles with the larger accumulator values first, as per API documentation.
Use a separate step to check distance between circles. Allows circles to be sorted by strength first. Avoids locking in EstimateRadius which was slowing it down.
Return centers only if maxRadius == 0 as per API documentation.

* Sort the circles so results are deterministic. Otherwise the order of circles with the same strength depends on parallel processing completion order.

* Add test for HoughCircles.

* Add beads test.

* Wrap the non-zero points structure in a common interface so the code can use either a vector or a matrix.

* Remove the special case for skipping the radius search if maxRadius==0.

* Add performance tests.

* Use NULL instead of nullptr.
OpenCV should compile with C++98 compiler.

* Put test suite name first.
Use different test suite names for each test to avoid an error from the test runner.

* Address build bot errors and warnings.

* Skip radius search if maxRadius < 0.

* Dynamically switch to NZPointList when it will be faster than NZPointSet.

* Fix compile error: missing 'typename' prior to dependent type name.

* Fix compile error: missing 'typename' prior to dependent type name.
This time fix it the non C++ 11 way.

* Fix compile error: no type named 'const_reference' in 'class cv::NZPointList'

* Disable ManySmallCircles tests. Failing on Mac.

* Change beads image to JPEG for smaller file size.
Try enabling the ManySmallCircles tests again.

* Remove ManySmallCircles tests. They are failing on the Mac build.

* Fix expectations to check all circles.

* Changing case on a case-insensitive file system
Step 1: remove the old file names

* Changing case on a case-insensitive file system
Step 2: add them back with the new names

* Fix cmpAccum function to be strictly weak ordered.

* Add tests for many small circles.

* imgproc(perf): fix HoughCircles tests

* imgproc(houghCircles): refactor code

- simplify NZPointList
- drop broken (de-synchronization of 'current'/'mi' fields) NZPointSet iterator
- NZPointSet iterator is replaced to direct area scan
- use SIMD intrinsics
- avoid std exceptions (build for embedded systems)

modules/imgproc/include/opencv2/imgproc.hpp

@@ -2094,8 +2094,8 @@ Example: :
 
 @note Usually the function detects the centers of circles well. However, it may fail to find correct
 radii. You can assist to the function by specifying the radius range ( minRadius and maxRadius ) if
-you know it. Or, you may set maxRadius to 0 to return centers only without radius search, and find the correct
-radius using an additional procedure.
+you know it. Or, you may set maxRadius to a negative number to return centers only without radius
+search, and find the correct radius using an additional procedure.
 
 @param image 8-bit, single-channel, grayscale input image.
 @param circles Output vector of found circles. Each vector is encoded as a 3-element
@@ -2114,7 +2114,8 @@ accumulator threshold for the circle centers at the detection stage. The smaller
 false circles may be detected. Circles, corresponding to the larger accumulator values, will be
 returned first.
 @param minRadius Minimum circle radius.
-@param maxRadius Maximum circle radius.
+@param maxRadius Maximum circle radius. If <= 0, uses the maximum image dimension. If < 0, returns
+centers without finding the radius.
 
 @sa fitEllipse, minEnclosingCircle
  */

modules/imgproc/perf/perf_houghcircles.cpp

+#include "perf_precomp.hpp"
+#include "opencv2/imgproc.hpp"
+#include "opencv2/imgproc/types_c.h"
+
+using namespace std;
+using namespace cv;
+using namespace perf;
+
+PERF_TEST(PerfHoughCircles, Basic)
+{
+    string filename = getDataPath("cv/imgproc/stuff.jpg");
+    const double dp = 1.0;
+    double minDist = 20;
+    double edgeThreshold = 20;
+    double accumThreshold = 30;
+    int minRadius = 20;
+    int maxRadius = 200;
+
+    Mat img = imread(filename, IMREAD_GRAYSCALE);
+    ASSERT_FALSE(img.empty()) << "Unable to load source image " << filename;
+
+    GaussianBlur(img, img, Size(9, 9), 2, 2);
+
+    vector<Vec3f> circles;
+    declare.in(img);
+
+    TEST_CYCLE()
+    {
+        HoughCircles(img, circles, CV_HOUGH_GRADIENT, dp, minDist, edgeThreshold, accumThreshold, minRadius, maxRadius);
+    }
+
+    SANITY_CHECK_NOTHING();
+}
+
+PERF_TEST(PerfHoughCircles2, ManySmallCircles)
+{
+    string filename = getDataPath("cv/imgproc/beads.jpg");
+    const double dp = 1.0;
+    double minDist = 10;
+    double edgeThreshold = 90;
+    double accumThreshold = 11;
+    int minRadius = 7;
+    int maxRadius = 18;
+
+    Mat img = imread(filename, IMREAD_GRAYSCALE);
+    ASSERT_FALSE(img.empty()) << "Unable to load source image " << filename;
+
+    vector<Vec3f> circles;
+    declare.in(img);
+
+    TEST_CYCLE()
+    {
+        HoughCircles(img, circles, CV_HOUGH_GRADIENT, dp, minDist, edgeThreshold, accumThreshold, minRadius, maxRadius);
+    }
+
+    SANITY_CHECK_NOTHING();
+}

modules/imgproc/test/test_houghcircles.cpp

+/*M///////////////////////////////////////////////////////////////////////////////////////
+//
+//  IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
+//
+//  By downloading, copying, installing or using the software you agree to this license.
+//  If you do not agree to this license, do not download, install,
+//  copy or use the software.
+//
+//
+//                           License Agreement
+//                For Open Source Computer Vision Library
+//
+// Copyright (C) 2000-2008, Intel Corporation, all rights reserved.
+// Copyright (C) 2009, Willow Garage Inc., all rights reserved.
+// Copyright (C) 2014, Itseez, Inc, all rights reserved.
+// Third party copyrights are property of their respective owners.
+//
+// Redistribution and use in source and binary forms, with or without modification,
+// are permitted provided that the following conditions are met:
+//
+//   * Redistribution's of source code must retain the above copyright notice,
+//     this list of conditions and the following disclaimer.
+//
+//   * Redistribution's in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//
+//   * The name of the copyright holders may not be used to endorse or promote products
+//     derived from this software without specific prior written permission.
+//
+// This software is provided by the copyright holders and contributors "as is" and
+// any express or implied warranties, including, but not limited to, the implied
+// warranties of merchantability and fitness for a particular purpose are disclaimed.
+// In no event shall the Intel Corporation or contributors be liable for any direct,
+// indirect, incidental, special, exemplary, or consequential damages
+// (including, but not limited to, procurement of substitute goods or services;
+// loss of use, data, or profits; or business interruption) however caused
+// and on any theory of liability, whether in contract, strict liability,
+// or tort (including negligence or otherwise) arising in any way out of
+// the use of this software, even if advised of the possibility of such damage.
+//
+//M*/
+
+#include "test_precomp.hpp"
+
+#ifndef DEBUG_IMAGES
+#define DEBUG_IMAGES 0
+#endif
+
+using namespace cv;
+using namespace std;
+
+static string getTestCaseName(const string& picture_name, double minDist, double edgeThreshold, double accumThreshold, int minRadius, int maxRadius)
+{
+    string results_name = format("circles_%s_%.0f_%.0f_%.0f_%d_%d",
+        picture_name.c_str(), minDist, edgeThreshold, accumThreshold, minRadius, maxRadius);
+    string temp(results_name);
+    size_t pos = temp.find_first_of("\\/.");
+    while (pos != string::npos) {
+        temp.replace(pos, 1, "_");
+        pos = temp.find_first_of("\\/.");
+    }
+    return temp;
+}
+
+#if DEBUG_IMAGES
+static void highlightCircles(const string& imagePath, const vector<Vec3f>& circles, const string& outputImagePath)
+{
+    Mat imgDebug = imread(imagePath, IMREAD_COLOR);
+    const Scalar yellow(0, 255, 255);
+
+    for (vector<Vec3f>::const_iterator iter = circles.begin(); iter != circles.end(); ++iter)
+    {
+        const Vec3f& circle = *iter;
+        float x = circle[0];
+        float y = circle[1];
+        float r = max(circle[2], 2.0f);
+        cv::circle(imgDebug, Point(int(x), int(y)), int(r), yellow);
+    }
+    imwrite(outputImagePath, imgDebug);
+}
+#endif
+
+typedef std::tr1::tuple<string, double, double, double, int, int> Image_MinDist_EdgeThreshold_AccumThreshold_MinRadius_MaxRadius_t;
+class HoughCirclesTestFixture : public testing::TestWithParam<Image_MinDist_EdgeThreshold_AccumThreshold_MinRadius_MaxRadius_t>
+{
+    string picture_name;
+    double minDist;
+    double edgeThreshold;
+    double accumThreshold;
+    int minRadius;
+    int maxRadius;
+
+public:
+    HoughCirclesTestFixture()
+    {
+        picture_name = std::tr1::get<0>(GetParam());
+        minDist = std::tr1::get<1>(GetParam());
+        edgeThreshold = std::tr1::get<2>(GetParam());
+        accumThreshold = std::tr1::get<3>(GetParam());
+        minRadius = std::tr1::get<4>(GetParam());
+        maxRadius = std::tr1::get<5>(GetParam());
+    }
+
+    HoughCirclesTestFixture(const string& picture, double minD, double edge, double accum, int minR, int maxR) :
+        picture_name(picture), minDist(minD), edgeThreshold(edge), accumThreshold(accum), minRadius(minR), maxRadius(maxR)
+    {
+    }
+
+    void run_test()
+    {
+        string test_case_name = getTestCaseName(picture_name, minDist, edgeThreshold, accumThreshold, minRadius, maxRadius);
+        string filename = cvtest::TS::ptr()->get_data_path() + picture_name;
+        Mat src = imread(filename, IMREAD_GRAYSCALE);
+        EXPECT_FALSE(src.empty()) << "Invalid test image: " << filename;
+
+        GaussianBlur(src, src, Size(9, 9), 2, 2);
+
+        vector<Vec3f> circles;
+        const double dp = 1.0;
+        HoughCircles(src, circles, CV_HOUGH_GRADIENT, dp, minDist, edgeThreshold, accumThreshold, minRadius, maxRadius);
+
+        string imgProc = string(cvtest::TS::ptr()->get_data_path()) + "imgproc/";
+#if DEBUG_IMAGES
+        highlightCircles(filename, circles, imgProc + test_case_name + ".png");
+#endif
+
+        string xml = imgProc + "HoughCircles.xml";
+        FileStorage fs(xml, FileStorage::READ);
+        FileNode node = fs[test_case_name];
+        if (node.empty())
+        {
+            fs.release();
+            fs.open(xml, FileStorage::APPEND);
+            EXPECT_TRUE(fs.isOpened()) << "Cannot open sanity data file: " << xml;
+            fs << test_case_name << circles;
+            fs.release();
+            fs.open(xml, FileStorage::READ);
+            EXPECT_TRUE(fs.isOpened()) << "Cannot open sanity data file: " << xml;
+        }
+
+        vector<Vec3f> exp_circles;
+        read(fs[test_case_name], exp_circles, vector<Vec3f>());
+        fs.release();
+
+        EXPECT_EQ(exp_circles.size(), circles.size());
+    }
+};
+
+TEST_P(HoughCirclesTestFixture, regression)
+{
+    run_test();
+}
+
+INSTANTIATE_TEST_CASE_P(ImgProc, HoughCirclesTestFixture, testing::Combine(
+    // picture_name:
+    testing::Values("imgproc/stuff.jpg"),
+    // minDist:
+    testing::Values(20),
+    // edgeThreshold:
+    testing::Values(20),
+    // accumThreshold:
+    testing::Values(30),
+    // minRadius:
+    testing::Values(20),
+    // maxRadius:
+    testing::Values(200)
+    ));
+
+TEST(HoughCirclesTest, DefaultMaxRadius)
+{
+    string picture_name = "imgproc/stuff.jpg";
+    const double dp = 1.0;
+    double minDist = 20;
+    double edgeThreshold = 20;
+    double accumThreshold = 30;
+    int minRadius = 20;
+    int maxRadius = 0;
+
+    string filename = cvtest::TS::ptr()->get_data_path() + picture_name;
+    Mat src = imread(filename, IMREAD_GRAYSCALE);
+    EXPECT_FALSE(src.empty()) << "Invalid test image: " << filename;
+
+    GaussianBlur(src, src, Size(9, 9), 2, 2);
+
+    vector<Vec3f> circles;
+    HoughCircles(src, circles, CV_HOUGH_GRADIENT, dp, minDist, edgeThreshold, accumThreshold, minRadius, maxRadius);
+
+#if DEBUG_IMAGES
+    string imgProc = string(cvtest::TS::ptr()->get_data_path()) + "imgproc/";
+    highlightCircles(filename, circles, imgProc + "HoughCirclesTest_DefaultMaxRadius.png");
+#endif
+
+    int maxDimension = std::max(src.rows, src.cols);
+
+    EXPECT_GT(circles.size(), size_t(0)) << "Should find at least some circles";
+    for (size_t i = 0; i < circles.size(); ++i)
+    {
+        EXPECT_GE(circles[i][2], minRadius) << "Radius should be >= minRadius";
+        EXPECT_LE(circles[i][2], maxDimension) << "Radius should be <= max image dimension";
+    }
+}
+
+TEST(HoughCirclesTest, CentersOnly)
+{
+    string picture_name = "imgproc/stuff.jpg";
+    const double dp = 1.0;
+    double minDist = 20;
+    double edgeThreshold = 20;
+    double accumThreshold = 30;
+    int minRadius = 20;
+    int maxRadius = -1;
+
+    string filename = cvtest::TS::ptr()->get_data_path() + picture_name;
+    Mat src = imread(filename, IMREAD_GRAYSCALE);
+    EXPECT_FALSE(src.empty()) << "Invalid test image: " << filename;
+
+    GaussianBlur(src, src, Size(9, 9), 2, 2);
+
+    vector<Vec3f> circles;
+    HoughCircles(src, circles, CV_HOUGH_GRADIENT, dp, minDist, edgeThreshold, accumThreshold, minRadius, maxRadius);
+
+#if DEBUG_IMAGES
+    string imgProc = string(cvtest::TS::ptr()->get_data_path()) + "imgproc/";
+    highlightCircles(filename, circles, imgProc + "HoughCirclesTest_CentersOnly.png");
+#endif
+
+    EXPECT_GT(circles.size(), size_t(0)) << "Should find at least some circles";
+    for (size_t i = 0; i < circles.size(); ++i)
+    {
+        EXPECT_EQ(circles[i][2], 0.0f) << "Did not ask for radius";
+    }
+}
+
+TEST(HoughCirclesTest, ManySmallCircles)
+{
+    string picture_name = "imgproc/beads.jpg";
+    const double dp = 1.0;
+    double minDist = 10;
+    double edgeThreshold = 90;
+    double accumThreshold = 11;
+    int minRadius = 7;
+    int maxRadius = 18;
+
+    string filename = cvtest::TS::ptr()->get_data_path() + picture_name;
+    Mat src = imread(filename, IMREAD_GRAYSCALE);
+    EXPECT_FALSE(src.empty()) << "Invalid test image: " << filename;
+
+    vector<Vec3f> circles;
+    HoughCircles(src, circles, CV_HOUGH_GRADIENT, dp, minDist, edgeThreshold, accumThreshold, minRadius, maxRadius);
+
+#if DEBUG_IMAGES
+    string imgProc = string(cvtest::TS::ptr()->get_data_path()) + "imgproc/";
+    string test_case_name = getTestCaseName(picture_name, minDist, edgeThreshold, accumThreshold, minRadius, maxRadius);
+    highlightCircles(filename, circles, imgProc + test_case_name + ".png");
+#endif
+
+    EXPECT_GT(circles.size(), size_t(3000)) << "Should find a lot of circles";
+}