Original code + comments

modules/line_descriptor/CMakeLists.txt

+#INCLUDE_DIRECTORIES(/data1/lz/LilianTests/ARPACKLAB/arpack++/include/)
+#INCLUDE_DIRECTORIES(/data1/lz/LilianTests/ARPACKLAB/arpack++)
+INCLUDE_DIRECTORIES(/usr/include/arpack++/include/)
+INCLUDE_DIRECTORIES(/usr/include/arpack++)
+
+#project name
+PROJECT(LILIANTESTS)
+
+cmake_minimum_required(VERSION 2.8)
+
+if(COMMAND cmake_policy)
+  cmake_policy(SET CMP0003 NEW)
+endif(COMMAND cmake_policy)
+
+SET(BUILD_SHARED_LIBS ON)
+
+## where are user-specific cmake modules
+SET(CMAKE_MODULE_PATH $ENV{CMAKE_MODULE_PATH})
+
+OPTION(USE_BIAS OFF)
+
+#IF(USE_BIAS)
+#FIND_PACKAGE(BIAS)
+#IF(BIAS_FOUND)
+#  INCLUDE(${BIAS_USE_FILE})
+#ELSE(BIAS_FOUND)
+#  MESSAGE(SEND_ERROR "BIAS lib not found.")
+#ENDIF(BIAS_FOUND)
+#ENDIF(USE_BIAS)
+
+
+IF(USE_BIAS)
+INCLUDE_DIRECTORIES(${BIAS_INCLUDE_DIR} /usr/local/include/BIAS /usr/include/ImageMagick /usr/local/include/opencv2 ${WXWIDGETS_INCLUDE_DIR})
+LINK_DIRECTORIES( ${BIAS_LINK_DIRECTORIES})
+ENDIF(USE_BIAS)
+  
+SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${BIAS_CXX_FLAGS} -std=c++0x")
+SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS}  ${BIAS_C_FLAGS}")
+
+# source files of library "LineMatchingLib" to be created
+SET(LineMatchingLib_SRCS
+    #src/PairwiseLineMatching.cpp
+    src/LineDescriptor.cpp
+    src/EDLineDetector.cpp
+)
+# header files to be installed
+SET(LineMatchingLib_HEADER
+    #include/PairwiseLineMatching.hh
+    include/LineDescriptor.hh
+    include/EDLineDetector.hh
+    include/LineStructure.hh
+)
+
+
+ADD_LIBRARY(LineMatchingLib
+            ${LineMatchingLib_SRCS}
+            ${LineMatchingLib_HEADER})
+TARGET_LINK_LIBRARIES(LineMatchingLib /usr/lib/libsuperlu.so opencv_core opencv_highgui opencv_imgproc) 
+
+
+#ADD_EXECUTABLE(TestLineMatchingAlgorithm src/TestLineMatchingAlgorithm.cpp)
+#TARGET_LINK_LIBRARIES(TestLineMatchingAlgorithm   LineMatchingLib )
+
+

modules/line_descriptor/include/opencv2/line_descriptor/LineDescriptor.hh

+/*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) 2011-2012, Lilian Zhang, all rights reserved.
+Copyright (C) 2013, Manuele Tamburrano, Stefano Fabri, 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:
+
+  * Redistributions of source code must retain the above copyright notice,
+    this list of conditions and the following disclaimer.
+
+  * Redistributions 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.
+*/
+
+#ifndef LINEDESCRIPTOR_HH_
+#define LINEDESCRIPTOR_HH_
+
+
+#include "EDLineDetector.hh"
+#include "LineStructure.hh"
+
+
+#include <map>
+struct OctaveLine{
+  unsigned int octaveCount;//the octave which this line is detected
+  unsigned int lineIDInOctave;//the line ID in that octave image
+  unsigned int lineIDInScaleLineVec;//the line ID in Scale line vector
+  float lineLength; //the length of line in original image scale
+};
+
+
+/* This class is used to generate the line descriptors from multi-scale images  */
+class LineDescriptor
+{
+public:
+	LineDescriptor(int n_octave);
+	LineDescriptor(unsigned int numOfBand, unsigned int widthOfBand, int n_octave);
+	~LineDescriptor();
+	enum{
+		NearestNeighbor=0, //the nearest neighbor is taken as matching
+		NNDR=1//nearest/next ratio
+	};
+  /*This function is used to detect lines from multi-scale images.*/
+	int OctaveKeyLines(cv::Mat & image, ScaleLines &keyLines);
+  int GetLineDescriptor(cv::Mat & image,
+  		ScaleLines &keyLines);
+  int GetLineDescriptor(cv::Mat & image,
+  		ScaleLines &keyLines, bool lsd);
+
+  void findNearestParallelLines(ScaleLines & keyLines);
+
+  void GetLineBinaryDescriptor(std::vector<cv::Mat> & oct_binaryDescMat, ScaleLines & keyLines);
+  int MatchLineByDescriptor(ScaleLines &keyLinesLeft, ScaleLines &keyLinesRight,
+  		std::vector<short> &matchLeft, std::vector<short> &matchRight,
+  		int criteria=NNDR);
+  float LowestThreshold;//global threshold for line descriptor distance, default is 0.35
+  float NNDRThreshold;//the NNDR threshold for line descriptor distance, default is 0.6
+  
+  int ksize_; //the size of Gaussian kernel: ksize X ksize, default value is 5.
+  unsigned int  numOfOctave_;//the number of image octave
+  unsigned int  numOfBand_;//the number of band used to compute line descriptor
+  unsigned int  widthOfBand_;//the width of band;
+  std::vector<float> gaussCoefL_;//the local gaussian coefficient apply to the orthogonal line direction within each band;
+  std::vector<float> gaussCoefG_;//the global gaussian coefficient apply to each Row within line support region
+  
+  
+private:
+
+	void sample(float *igray,float *ogray, float factor, int width, int height)
+	{
+
+		int swidth = (int)((float) width / factor);
+		int sheight = (int)((float) height / factor);
+
+		for(int j=0; j < sheight; j++)
+		 for(int i=0; i < swidth; i++)
+			ogray[j*swidth + i] = igray[(int)((float) j * factor) * width + (int) ((float) i*factor)];
+
+	}
+	void sampleUchar(uchar *igray,uchar *ogray, float factor, int width, int height)
+    {
+
+        int swidth = (int)((float) width / factor);
+        int sheight = (int)((float) height / factor);
+
+        for(int j=0; j < sheight; j++)
+         for(int i=0; i < swidth; i++)
+            ogray[j*swidth + i] = igray[(int)((float) j * factor) * width + (int) ((float) i*factor)];
+
+    }
+	/*Compute the line descriptor of input line set. This function should be called
+	 *after OctaveKeyLines() function; */
+	int ComputeLBD_(ScaleLines &keyLines);
+	/*For each octave of image, we define an EDLineDetector, because we can get gradient images (dxImg, dyImg, gImg)
+	 *from the EDLineDetector class without extra computation cost. Another reason is that, if we use
+	 *a single EDLineDetector to detect lines in different octave of images, then we need to allocate and release
+	 *memory for gradient images (dxImg, dyImg, gImg) repeatedly for their varying size*/
+	std::vector<EDLineDetector*> edLineVec_;
+
+	
+};
+
+
+
+
+
+
+#endif /* LINEDESCRIPTOR_HH_ */

modules/line_descriptor/include/opencv2/line_descriptor/LineStructure.hh

+/*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) 2011-2012, Lilian Zhang, all rights reserved.
+Copyright (C) 2013, Manuele Tamburrano, Stefano Fabri, 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:
+
+  * Redistributions of source code must retain the above copyright notice,
+    this list of conditions and the following disclaimer.
+
+  * Redistributions 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.
+*/
+
+#ifndef LINESTRUCTURE_HH_
+#define LINESTRUCTURE_HH_
+
+#include <vector>
+// A 2D line (normal equation parameters).
+struct SingleLine
+{
+	//note: rho and theta are based on coordinate origin, i.e. the top-left corner of image
+	double rho;//unit: pixel length
+	double theta;//unit: rad
+	double linePointX;// = rho * cos(theta);
+	double linePointY;// = rho * sin(theta);
+	//for EndPoints, the coordinate origin is the top-left corner of image.
+	double startPointX;
+	double startPointY;
+	double endPointX;
+	double endPointY;
+	//direction of a line, the angle between positive line direction (dark side is in the left) and positive X axis.
+	double direction;
+	//mean gradient magnitude
+	double gradientMagnitude;
+	//mean gray value of pixels in dark side of line
+	double darkSideGrayValue;
+	//mean gray value of pixels in light side of line
+	double lightSideGrayValue;
+	//the length of line
+	double lineLength;
+	//the width of line;
+	double width;
+	//number of pixels
+	int numOfPixels;
+	//the decriptor of line
+	std::vector<double> descriptor;
+};
+
+// Specifies a vector of lines.
+typedef std::vector<SingleLine> Lines_list;
+
+struct OctaveSingleLine
+{
+	/*endPoints, the coordinate origin is the top-left corner of the original image.
+	 *startPointX = sPointInOctaveX * (factor)^octaveCount;	*/
+	float startPointX;
+	float startPointY;
+	float endPointX;
+	float endPointY;
+	//endPoints, the coordinate origin is the top-left corner of the octave image.
+	float sPointInOctaveX;
+	float sPointInOctaveY;
+	float ePointInOctaveX;
+	float ePointInOctaveY;
+	//direction of a line, the angle between positive line direction (dark side is in the left) and positive X axis.
+	float direction;
+	//the summation of gradient magnitudes of pixels on lines
+	float salience;
+	//the length of line
+	float lineLength;
+	//number of pixels
+	unsigned int numOfPixels;
+	//the octave which this line is detected
+	unsigned int octaveCount;
+	//the decriptor of line
+	std::vector<float> descriptor;
+};
+
+// Specifies a vector of lines.
+typedef std::vector<OctaveSingleLine> LinesVec;
+
+typedef std::vector<LinesVec> ScaleLines;//each element in ScaleLines is a vector of lines which corresponds the same line detected in different octave images.
+
+#endif /* LINESTRUCTURE_HH_ */