implemented mean shift segmentation with elimination of small segments, added tests

modules/gpu/include/opencv2/gpu/gpu.hpp

@@ -473,6 +473,10 @@ namespace cv
         CV_EXPORTS void meanShiftProc(const GpuMat& src, GpuMat& dstr, GpuMat& dstsp, int sp, int sr, 
             TermCriteria criteria = TermCriteria(TermCriteria::MAX_ITER + TermCriteria::EPS, 5, 1));
 
+        //! Does mean shift segmentation with elimiation of small regions.
+        CV_EXPORTS void meanShiftSegmentation(const GpuMat& src, Mat& dst, int sp, int sr, int minsize,
+            TermCriteria criteria = TermCriteria(TermCriteria::MAX_ITER + TermCriteria::EPS, 5, 1));
+
         //! Does coloring of disparity image: [0..ndisp) -> [0..240, 1, 1] in HSV.
         //! Supported types of input disparity: CV_8U, CV_16S.
         //! Output disparity has CV_8UC4 type in BGRA format (alpha = 255).

modules/gpu/src/mssegmentation.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.
+// 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 <time.h>
+#include <vector>
+#include "precomp.hpp"
+
+#if !defined(HAVE_CUDA)
+
+namespace cv
+{
+namespace gpu
+{
+
+void meanShiftSegmentation(const GpuMat&, Mat&, int, int, int, TermCriteria) { throw_nogpu(); }
+
+} // namespace gpu
+} // namespace cv
+
+#else
+
+//#define _MSSEGMENTATION_DBG
+
+#ifdef _MSSEGMENTATION_DBG
+#include <iostream>
+#define LOG(s) std::cout << (s) << std::endl
+#define LOG2(s1, s2) std::cout << (s1) << (s2) << std::endl
+#define DBG(code) code
+#else
+#define LOG(s1)
+#define LOG2(s1, s2)
+#define DBG(code)
+#endif
+
+#define PIX(y, x) ((y) * ncols + (x))
+
+using namespace std;
+
+// Auxiliray stuff
+namespace
+{
+
+//
+// Declarations
+//
+
+class DjSets
+{
+public:
+    DjSets(int n);
+    ~DjSets();
+    int find(int elem) const;
+    int merge(int set1, int set2);
+
+    int* parent;
+    int* rank;
+    int* size;
+private:
+    DjSets(const DjSets&) {}
+    DjSets operator =(const DjSets&) {}
+};
+
+
+template <typename T>
+struct GraphEdge
+{
+    GraphEdge() {}
+    GraphEdge(int to, int next, const T& val) : to(to), next(next), val(val) {}
+    int to;
+    int next;
+    T val;
+};
+
+
+template <typename T>
+class Graph
+{
+public:
+    typedef GraphEdge<T> Edge;
+
+    Graph(int numv, int nume_max);
+    ~Graph();
+
+    void addEdge(int from, int to, const T& val=T());
+
+    int* start;
+    Edge* edges;
+
+    int numv;
+    int nume_max;
+    int nume;
+private:
+    Graph(const Graph&) {}
+    Graph operator =(const Graph&) {}
+};
+
+
+struct SegmLinkVal
+{
+    SegmLinkVal() {}
+    SegmLinkVal(int dr, int dsp) : dr(dr), dsp(dsp) {}
+    bool operator <(const SegmLinkVal& other) const
+    {
+        return dr + dsp < other.dr + other.dsp;
+    }
+    int dr;
+    int dsp;
+};
+
+
+struct SegmLink
+{
+    SegmLink() {}
+    SegmLink(int from, int to, const SegmLinkVal& val) 
+        : from(from), to(to), val(val) {}
+    int from;
+    int to;
+    SegmLinkVal val;
+};
+
+
+struct SegmLinkCmp
+{
+    bool operator ()(const SegmLink& lhs, const SegmLink& rhs) const
+    {
+        return lhs.val < rhs.val;
+    }
+};
+
+//
+// Implementation
+//
+
+DjSets::DjSets(int n)
+{
+    parent = new int[n];
+    rank = new int[n];
+    size = new int[n];   
+    for (int i = 0; i < n; ++i)
+    {
+        parent[i] = i;
+        rank[i] = 0;
+        size[i] = 1;
+    }
+}
+
+
+DjSets::~DjSets()
+{
+    delete[] parent;
+    delete[] rank;
+    delete[] size;
+}
+
+
+inline int DjSets::find(int elem) const
+{
+    int set = elem;
+    while (set != parent[set])
+        set = parent[set];
+    while (elem != parent[elem])
+    {
+        int next = parent[elem];
+        parent[elem] = set;
+        elem = next;
+    }
+    return set;
+}
+
+
+inline int DjSets::merge(int set1, int set2)
+{
+    if (rank[set1] < rank[set2])
+    {
+        parent[set1] = set2;
+        size[set2] += size[set1];
+        return set2;
+    }
+    if (rank[set2] < rank[set1])
+    {
+        parent[set2] = set1;
+        size[set1] += size[set2];
+        return set1;
+    }
+    parent[set1] = set2;
+    rank[set2]++;
+    size[set2] += size[set1];
+    return set2;
+}
+
+
+template <typename T>
+Graph<T>::Graph(int numv, int nume_max)
+{
+    this->numv = numv;
+    this->nume_max = nume_max;
+    start = new int[numv];
+    for (int i = 0; i < numv; ++i)
+        start[i] = -1;
+    edges = new Edge[nume_max];
+    nume = 0;
+}
+
+
+template <typename T>
+Graph<T>::~Graph()
+{
+    delete[] start;
+    delete[] edges;
+}
+
+
+template <typename T>
+inline void Graph<T>::addEdge(int from, int to, const T& val)
+{
+    Edge* edge = edges + nume;
+    new (edge) SegmLink(to, start[from], val);
+    start[from] = nume;
+    nume++;
+}
+
+
+inline int sqr(int x)
+{
+    return x * x;
+}
+
+} // anonymous namespace
+
+
+namespace cv
+{
+namespace gpu
+{
+
+void meanShiftSegmentation(const GpuMat& src, Mat& dst, int sp, int sr, int minsize, TermCriteria criteria)
+{
+    CV_Assert(src.type() == CV_8UC4);
+    const int nrows = src.rows;
+    const int ncols = src.cols;
+    const int hr = sr;
+    const int hsp = sp;
+
+    DBG(clock_t start = clock());
+
+    // Perform mean shift procedure and obtain region and spatial maps
+    GpuMat h_rmap, h_spmap;
+    meanShiftProc(src, h_rmap, h_spmap, sp, sr, criteria);
+    Mat rmap = h_rmap;
+    Mat spmap = h_spmap;
+
+    LOG2("meanshift:", clock() - start);
+    DBG(start = clock());
+
+    Graph<SegmLinkVal> g(nrows * ncols, 4 * (nrows - 1) * (ncols - 1)
+                                        + (nrows - 1) + (ncols - 1));
+
+    LOG2("ragalloc:", clock() - start);
+    DBG(start = clock());
+
+    // Make region adjacent graph from image
+    // TODO: SSE?
+    Vec4b r1;
+    Vec4b r2[4];
+    Point_<short> sp1;
+    Point_<short> sp2[4];
+    int dr[4];
+    int dsp[4];
+    for (int y = 0; y < nrows - 1; ++y)
+    {
+        Vec4b* ry = rmap.ptr<Vec4b>(y);
+        Vec4b* ryp = rmap.ptr<Vec4b>(y + 1);
+        Point_<short>* spy = spmap.ptr<Point_<short> >(y);
+        Point_<short>* spyp = spmap.ptr<Point_<short> >(y + 1);
+        for (int x = 0; x < ncols - 1; ++x)
+        {
+            r1 = ry[x];
+            sp1 = spy[x];
+
+            r2[0] = ry[x + 1];
+            r2[1] = ryp[x];
+            r2[2] = ryp[x + 1];
+            r2[3] = ryp[x];
+
+            sp2[0] = spy[x + 1];
+            sp2[1] = spyp[x];
+            sp2[2] = spyp[x + 1];
+            sp2[3] = spyp[x];
+
+            dr[0] = sqr(r1[0] - r2[0][0]) + sqr(r1[1] - r2[0][1]) + sqr(r1[2] - r2[0][2]);
+            dr[1] = sqr(r1[0] - r2[1][0]) + sqr(r1[1] - r2[1][1]) + sqr(r1[2] - r2[1][2]);
+            dr[2] = sqr(r1[0] - r2[2][0]) + sqr(r1[1] - r2[2][1]) + sqr(r1[2] - r2[2][2]);
+            dsp[0] = sqr(sp1.x - sp2[0].x) + sqr(sp1.y - sp2[0].y);
+            dsp[1] = sqr(sp1.x - sp2[1].x) + sqr(sp1.y - sp2[1].y);
+            dsp[2] = sqr(sp1.x - sp2[2].x) + sqr(sp1.y - sp2[2].y); 
+
+            r1 = ry[x + 1];
+            sp1 = spy[x + 1];
+
+            dr[3] = sqr(r1[0] - r2[3][0]) + sqr(r1[1] - r2[3][1]) + sqr(r1[2] - r2[3][2]);
+            dsp[3] = sqr(sp1.x - sp2[3].x) + sqr(sp1.y - sp2[3].y); 
+
+            g.addEdge(PIX(y, x), PIX(y, x + 1), SegmLinkVal(dr[0], dsp[0]));
+            g.addEdge(PIX(y, x), PIX(y + 1, x), SegmLinkVal(dr[1], dsp[1]));
+            g.addEdge(PIX(y, x), PIX(y + 1, x + 1), SegmLinkVal(dr[2], dsp[2]));
+            g.addEdge(PIX(y, x + 1), PIX(y, x + 1), SegmLinkVal(dr[3], dsp[3]));
+        }
+    }
+    for (int y = 0; y < nrows - 1; ++y)
+    {
+        r1 = rmap.at<Vec4b>(y, ncols - 1);
+        r2[0] = rmap.at<Vec4b>(y + 1, ncols - 1);
+        sp1 = spmap.at<Point_<short> >(y, ncols - 1);
+        sp2[0] = spmap.at<Point_<short> >(y + 1, ncols - 1);
+        dr[0] = sqr(r1[0] - r2[0][0]) + sqr(r1[1] - r2[0][1]) + sqr(r1[2] - r2[0][2]);
+        dsp[0] = sqr(sp1.x - sp2[0].x) + sqr(sp1.y - sp2[0].y);   
+        g.addEdge(PIX(y, ncols - 1), PIX(y + 1, ncols - 1), SegmLinkVal(dr[0], dsp[0]));
+    }
+    for (int x = 0; x < ncols - 1; ++x)
+    {
+        r1 = rmap.at<Vec4b>(nrows - 1, x);
+        r2[0] = rmap.at<Vec4b>(nrows - 1, x + 1);
+        sp1 = spmap.at<Point_<short> >(nrows - 1, x);
+        sp2[0] = spmap.at<Point_<short> >(nrows - 1, x + 1);
+        dr[0] = sqr(r1[0] - r2[0][0]) + sqr(r1[1] - r2[0][1]) + sqr(r1[2] - r2[0][2]);
+        dsp[0] = sqr(sp1.x - sp2[0].x) + sqr(sp1.y - sp2[0].y);   
+        g.addEdge(PIX(nrows - 1, x), PIX(nrows - 1, x + 1), SegmLinkVal(dr[0], dsp[0]));
+    }
+
+    LOG2("raginit:", clock() - start);
+    DBG(start = clock());
+
+    DjSets comps(g.numv);
+
+    LOG2("djsetinit:", clock() - start);
+    DBG(start = clock());
+
+    // Find adjacent components
+    for (int v = 0; v < g.numv; ++v)
+    {
+        for (int e_it = g.start[v]; e_it != -1; e_it = g.edges[e_it].next)
+        {
+            int comp1 = comps.find(v);
+            int comp2 = comps.find(g.edges[e_it].to);
+            if (comp1 != comp2 && g.edges[e_it].val.dr < hr 
+                               && g.edges[e_it].val.dsp < hsp)
+                comps.merge(comp1, comp2);
+        }
+    }
+
+    LOG2("findadjacent:", clock() - start);
+    DBG(start = clock());
+
+    vector<SegmLink> edges;
+    edges.reserve(g.numv);
+
+    LOG2("initedges:", clock() - start);
+    DBG(start = clock());
+
+    for (int v = 0; v < g.numv; ++v)
+    {
+        int comp1 = comps.find(v);
+        for (int e_it = g.start[v]; e_it != -1; e_it = g.edges[e_it].next)
+        {
+            int comp2 = comps.find(g.edges[e_it].to);
+            if (comp1 != comp2)
+                edges.push_back(SegmLink(comp1, comp2, g.edges[e_it].val));
+        }
+    }
+
+    LOG2("prepareforsort:", clock() - start);
+    DBG(start = clock());
+
+    // Sort all graph's edges connecting differnet components (in asceding order)
+    sort(edges.begin(), edges.end(), SegmLinkCmp());
+
+    LOG2("sortedges:", clock() - start);
+    DBG(start = clock());
+
+    // Exclude small components (starting from the nearest couple)
+    vector<SegmLink>::iterator e_it = edges.begin();
+    for (; e_it != edges.end(); ++e_it)
+    {
+        int comp1 = comps.find(e_it->from);
+        int comp2 = comps.find(e_it->to);
+        if (comp1 != comp2 && (comps.size[comp1] < minsize || comps.size[comp2] < minsize))
+            comps.merge(comp1, comp2);
+    }
+
+    LOG2("excludesmall:", clock() - start);
+    DBG(start = clock());
+
+    // Compute sum of the pixel's colors which are in the same segment
+    Mat h_src = src;
+    vector<Vec4i> sumcols(nrows * ncols, Vec4i(0, 0, 0, 0));
+    for (int y = 0; y < nrows; ++y)
+    {
+        Vec4b* h_srcy = h_src.ptr<Vec4b>(y);
+        for (int x = 0; x < ncols; ++x)
+        {
+            int parent = comps.find(PIX(y, x));
+            Vec4b col = h_srcy[x];
+            Vec4i& sumcol = sumcols[parent];
+            sumcol[0] += col[0];
+            sumcol[1] += col[1];
+            sumcol[2] += col[2];
+        }
+    }
+
+    LOG2("computesum:", clock() - start);
+    DBG(start = clock());
+
+    // Create final image, color of each segment is the average color of its pixels
+    dst.create(src.size(), src.type());
+
+    for (int y = 0; y < nrows; ++y)
+    {
+        Vec4b* dsty = dst.ptr<Vec4b>(y);
+        for (int x = 0; x < ncols; ++x)
+        {
+            int parent = comps.find(PIX(y, x));
+            const Vec4i& sumcol = sumcols[parent];
+            Vec4b& dstcol = dsty[x];
+            dstcol[0] = static_cast<uchar>(sumcol[0] / comps.size[parent]);
+            dstcol[1] = static_cast<uchar>(sumcol[1] / comps.size[parent]);
+            dstcol[2] = static_cast<uchar>(sumcol[2] / comps.size[parent]);
+        }
+    }
+
+    LOG2("createfinal:", clock() - start);
+}
+
+} // namespace gpu
+} // namespace cv
+
+#endif // #if !defined (HAVE_CUDA)
\ No newline at end of file

tests/gpu/src/mssegmentation.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.
+//
+//
+//                        Intel License Agreement
+//                For Open Source Computer Vision Library
+//
+// Copyright (C) 2000, Intel Corporation, 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 Intel Corporation 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 <opencv2/opencv.hpp>
+#include <opencv2/gpu/gpu.hpp>
+#include <iostream>
+#include <string>
+#include <iosfwd>
+#include "gputest.hpp"
+using namespace cv;
+using namespace cv::gpu;
+using namespace std;
+
+struct CV_GpuMeanShiftSegmentationTest : public CvTest {
+    CV_GpuMeanShiftSegmentationTest() : CvTest( "GPU-MeanShiftSegmentation", "MeanShiftSegmentation" ) {}
+
+    void run(int) 
+    {
+        try 
+        {
+            Mat img_rgb = imread(string(ts->get_data_path()) + "meanshift/cones.png");
+            if (img_rgb.empty())
+            {
+                ts->set_failed_test_info(CvTS::FAIL_MISSING_TEST_DATA);
+                return;
+            }
+
+            Mat img;
+            cvtColor(img_rgb, img, CV_BGR2BGRA);
+
+            for (int minsize = 0; minsize < 2000; minsize = (minsize + 1) * 2) 
+            {
+                stringstream path;
+                path << ts->get_data_path() << "meanshift/cones_segmented_sp10_sr10_minsize" << minsize << ".png";
+
+                Mat dst;
+                meanShiftSegmentation((GpuMat)img, dst, 10, 10, minsize);
+                Mat dst_rgb;
+                cvtColor(dst, dst_rgb, CV_BGRA2BGR);
+
+                //imwrite(path.str(), dst_rgb);
+                Mat dst_ref = imread(path.str());
+                if (dst_ref.empty()) 
+                {
+                    ts->set_failed_test_info(CvTS::FAIL_MISSING_TEST_DATA);
+                    return;
+                }
+                if (abs(cv::norm(dst_rgb - dst_ref, NORM_INF)) > 1e-3) 
+                {
+                    ts->printf(CvTS::LOG, "\ndiffers from image *minsize%d.png\n", minsize);
+                    ts->set_failed_test_info(CvTS::FAIL_BAD_ACCURACY);
+                    return;
+                }
+            }
+        }
+        catch (const cv::Exception& e) 
+        {
+            if (!check_and_treat_gpu_exception(e, ts))
+                throw;
+            return;
+        }
+
+        ts->set_failed_test_info(CvTS::OK);
+    }    
+} ms_segm_test;
\ No newline at end of file