Rewrote GraphSegmentation in ximgproc

modules/ximgproc/doc/ximgproc.bib

@@ -56,6 +56,17 @@
   organization={IEEE}
 }
 
+@incollection{PFF2004,
+  title={Efficient graph-based image segmentation},
+  author={Felzenszwalb, Pedro F and Huttenlocher, Daniel P},
+  journal={International Journal of Computer Vision},
+  volume={59},
+  number={2},
+  pages={167--181},
+  year={2004},
+  publisher={Springer}
+}
+
 @article{Min2014,
   title={Fast global image smoothing based on weighted least squares},
   author={Min, Dongbo and Choi, Sunghwan and Lu, Jiangbo and Ham, Bumsub and Sohn, Kwanghoon and Do, Minh N},

modules/ximgproc/include/opencv2/ximgproc.hpp

@@ -42,6 +42,7 @@
 #include "ximgproc/sparse_match_interpolator.hpp"
 #include "ximgproc/structured_edge_detection.hpp"
 #include "ximgproc/seeds.hpp"
+#include "ximgproc/segmentation.hpp"
 #include "ximgproc/fast_hough_transform.hpp"
 
 /** @defgroup ximgproc Extended Image Processing
@@ -54,6 +55,8 @@ which somehow takes into account pixel affinities in natural images.
     @defgroup ximgproc_filters Filters
 
     @defgroup ximgproc_superpixel Superpixels
+
+    @defgroup ximgproc_segmentation Image segmentation
   @}
 */
 

modules/ximgproc/include/opencv2/ximgproc/segmentation.hpp

+/*
+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
+                       (3-clause BSD License)
+Copyright (C) 2013, OpenCV Foundation, 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.
+  * Neither the names of the copyright holders nor the names of the contributors
+    may 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 copyright holders 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 __OPENCV_XIMGPROC_SEGMENTATION_HPP__
+#define __OPENCV_XIMGPROC_SEGMENTATION_HPP__
+
+#include <opencv2/core.hpp>
+
+namespace cv {
+    namespace ximgproc {
+        namespace segmentation {
+            //! @addtogroup ximgproc_segmentation
+            //! @{
+
+                    /** @brief Graph Based Segmentation Algorithm.
+                        The class implements the algorithm described in @cite PFF2004 .
+                     */
+                    class CV_EXPORTS_W GraphSegmentation : public Algorithm {
+                        public:
+                            /** @brief Segment an image and store output in dst
+                                @param src The input image. Any number of channel (1 (Eg: Gray), 3 (Eg: RGB), 4 (Eg: RGB-D)) can be provided
+                                @param dst The output segmentation. It's a CV_32SC1 Mat with the same number of cols and rows as input image, with an unique, sequential, id for each pixel.
+                            */
+                            CV_WRAP virtual void processImage(InputArray src, OutputArray dst) = 0;
+
+                            CV_WRAP virtual void setSigma(double sigma) = 0;
+                            CV_WRAP virtual double getSigma() = 0;
+
+                            CV_WRAP virtual void setK(float k) = 0;
+                            CV_WRAP virtual float getK() = 0;
+
+                            CV_WRAP virtual void setMinSize(int min_size) = 0;
+                            CV_WRAP virtual int getMinSize() = 0;
+                    };
+
+                    /** @brief Creates a graph based segmentor
+                        @param simga The sigma parameter, used to smooth image
+                        @param k The k parameter of the algorythm
+                        @param min_size The minimum size of segments
+                     */
+                    CV_EXPORTS_W Ptr<GraphSegmentation> createGraphSegmentation(double sigma=0.5, float k=300, int min_size=100);
+            //! @}
+
+            // Represent an edge between two pixels
+            class Edge {
+                public:
+                    int from;
+                    int to;
+                    float weight;
+
+                    bool operator <(const Edge& e) const {
+                        return weight < e.weight;
+                    }
+            };
+
+            // A point in the sets of points
+            class PointSetElement {
+                public:
+                    int p;
+                    int size;
+
+                    PointSetElement() { }
+
+                    PointSetElement(int p_) {
+                        p = p_;
+                        size = 1;
+                    }
+            };
+
+            // An object to manage set of points, who can be fusionned
+            class PointSet {
+                public:
+                    PointSet(int nb_elements_);
+                    ~PointSet();
+
+                    int nb_elements;
+
+                    // Return the main point of the point's set
+                    int getBasePoint(int p);
+
+                    // Join two sets of points, based on their main point
+                    void joinPoints(int p_a, int p_b);
+
+                    // Return the set size of a set (based on the main point)
+                    int size(unsigned int p) { return mapping[p].size; }
+
+                private:
+                    PointSetElement* mapping;
+
+            };
+
+        }
+    }
+}
+
+#endif

modules/ximgproc/samples/cpp/graphsegmentation_demo.cpp

+/*
+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
+                       (3-clause BSD License)
+Copyright (C) 2013, OpenCV Foundation, 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.
+  * Neither the names of the copyright holders nor the names of the contributors
+    may 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 copyright holders 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.
+*/
+
+
+#include "opencv2/ximgproc/segmentation.hpp"
+#include "opencv2/highgui.hpp"
+#include <opencv2/core/utility.hpp>
+#include <opencv2/opencv.hpp>
+#include <iostream>
+
+using namespace cv;
+using namespace cv::ximgproc::segmentation;
+
+static void help() {
+    std::cout << std::endl <<
+    "A program demonstrating the use and capabilities of a particular graph based image" << std::endl <<
+    "segmentation algorithm described in P. Felzenszwalb, D. Huttenlocher," << std::endl <<
+    "             \"Efficient Graph-Based Image Segmentation\"" << std::endl <<
+    "International Journal of Computer Vision, Vol. 59, No. 2, September 2004" << std::endl << std::endl <<
+    "Usage:" << std::endl <<
+    "./graphsegmentation_demo input_image output_image [simga=0.5] [k=300] [min_size=100]" << std::endl;
+}
+
+Scalar hsv_to_rgb(Scalar c) {
+    Mat in(1, 1, CV_32FC3);
+    Mat out(1, 1, CV_32FC3);
+
+    float * p = in.ptr<float>(0);
+
+    p[0] = c[0] * 360;
+    p[1] = c[1];
+    p[2] = c[2];
+
+    cvtColor(in, out, COLOR_HSV2RGB);
+
+    Scalar t;
+
+    Vec3f p2 = out.at<Vec3f>(0, 0);
+
+    t[0] = (int)(p2[0] * 255);
+    t[1] = (int)(p2[1] * 255);
+    t[2] = (int)(p2[2] * 255);
+
+    return t;
+
+}
+
+Scalar color_mapping(int segment_id) {
+
+    double base = (double)(segment_id) * 0.618033988749895 + 0.24443434;
+
+    return hsv_to_rgb(Scalar(fmod(base, 1.2), 0.95, 0.80));
+
+}
+
+int main(int argc, char** argv) {
+
+    if (argc < 2 || argc > 6) {
+        help();
+        return -1;
+    }
+
+    setUseOptimized(true);
+    setNumThreads(8);
+
+    Ptr<GraphSegmentation> gs = createGraphSegmentation();
+
+    if (argc > 3)
+        gs->setSigma(atof(argv[3]));
+
+    if (argc > 4)
+        gs->setK(atoi(argv[4]));
+
+    if (argc > 5)
+        gs->setMinSize(atoi(argv[5]));
+
+    if (!gs) {
+        std::cerr << "Failed to create GraphSegmentation Algorithm." << std::endl;
+        return -2;
+    }
+
+    Mat input, output, output_image;
+
+    input = imread(argv[1]);
+
+    if (!input.data) {
+        std::cerr << "Failed to load input image" << std::endl;
+        return -3;
+    }
+
+    gs->processImage(input, output);
+
+    double min, max;
+    minMaxLoc(output, &min, &max);
+
+    int nb_segs = (int)max + 1;
+
+    std::cout << nb_segs << " segments" << std::endl;
+
+    output_image = Mat::zeros(output.rows, output.cols, CV_8UC3);
+
+    uint* p;
+    uchar* p2;
+
+    for (int i = 0; i < output.rows; i++) {
+
+        p = output.ptr<uint>(i);
+        p2 = output_image.ptr<uchar>(i);
+
+        for (int j = 0; j < output.cols; j++) {
+            Scalar color = color_mapping(p[j]);
+            p2[j*3] = color[0];
+            p2[j*3 + 1] = color[1];
+            p2[j*3 + 2] = color[2];
+        }
+    }
+
+    imwrite(argv[2], output_image);
+
+    std::cout << "Image written to " << argv[2] << std::endl;
+
+    return 0;
+}

modules/ximgproc/src/precomp.hpp

@@ -34,8 +34,8 @@
  *  the use of this software, even if advised of the possibility of such damage.
  */
 
-#ifndef _OPENCV_EDGEFILTER_PRECOMP_HPP_
-#define _OPENCV_EDGEFILTER_PRECOMP_HPP_
+#ifndef _OPENCV_XIMGPROC_PRECOMP_HPP_
+#define _OPENCV_XIMGPROC_PRECOMP_HPP_
 
 #include <opencv2/core.hpp>
 #include <opencv2/core/ocl.hpp>
@@ -48,4 +48,7 @@
 
 #include <opencv2/ximgproc.hpp>
 
-#endif
\ No newline at end of file
+#include <algorithm>
+#include <map>
+
+#endif