Added HOG features to the traincascade module

modules/traincascade/CMakeLists.txt

@@ -22,6 +22,7 @@ set(traincascade_files traincascade.cpp
     boost.cpp boost.h features.cpp traincascade_features.h
     haarfeatures.cpp haarfeatures.h
     lbpfeatures.cpp lbpfeatures.h
+	HOGfeatures.cpp HOGfeatures.h
     imagestorage.cpp imagestorage.h)
 
 set(the_target opencv_traincascade)    

modules/traincascade/HOGfeatures.cpp

+#include "HOGfeatures.h"
+#include "cascadeclassifier.h"
+
+
+CvHOGFeatureParams::CvHOGFeatureParams()
+{
+    maxCatCount = 0;
+    name = HOGF_NAME;
+    featSize = N_BINS * N_CELLS;
+}
+
+void CvHOGEvaluator::init(const CvFeatureParams *_featureParams, int _maxSampleCount, Size _winSize)
+{
+    CV_Assert( _maxSampleCount > 0);
+    int cols = (_winSize.width + 1) * (_winSize.height + 1);
+    for (int bin = 0; bin < N_BINS; bin++)
+    {
+        hist.push_back(Mat(_maxSampleCount, cols, CV_32FC1));
+    }
+    normSum.create( (int)_maxSampleCount, cols, CV_32FC1 );
+    CvFeatureEvaluator::init( _featureParams, _maxSampleCount, _winSize );
+}
+
+void CvHOGEvaluator::setImage(const Mat &img, uchar clsLabel, int idx)
+{
+    CV_DbgAssert( !hist.empty());
+    CvFeatureEvaluator::setImage( img, clsLabel, idx );
+    vector<Mat> integralHist;
+    for (int bin = 0; bin < N_BINS; bin++)
+    {
+        integralHist.push_back( Mat(winSize.height + 1, winSize.width + 1, hist[bin].type(), hist[bin].ptr<float>((int)idx)) );
+    }
+    Mat integralNorm(winSize.height + 1, winSize.width + 1, normSum.type(), normSum.ptr<float>((int)idx));
+    integralHistogram(img, integralHist, integralNorm, (int)N_BINS);
+}
+
+//void CvHOGEvaluator::writeFeatures( FileStorage &fs, const Mat& featureMap ) const
+//{
+//    _writeFeatures( features, fs, featureMap );
+//}
+
+void CvHOGEvaluator::writeFeatures( FileStorage &fs, const Mat& featureMap ) const
+{
+    int featIdx;
+    int componentIdx;
+    const Mat_<int>& featureMap_ = (const Mat_<int>&)featureMap;
+    fs << FEATURES << "[";
+    for ( int fi = 0; fi < featureMap.cols; fi++ )
+        if ( featureMap_(0, fi) >= 0 )
+        {
+            fs << "{";
+            featIdx = fi / getFeatureSize();
+            componentIdx = fi % getFeatureSize();
+            features[featIdx].write( fs, componentIdx );
+            fs << "}";
+        }
+    fs << "]";  
+}
+
+void CvHOGEvaluator::generateFeatures()
+{
+    int offset = winSize.width + 1;
+    Size blockStep;
+    int x, y, t, w, h;
+
+    for (t = 8; t <= winSize.width/2; t+=8) //t = size of a cell. blocksize = 4*cellSize
+    {
+        blockStep = Size(4,4);
+        w = 2*t; //width of a block
+        h = 2*t; //height of a block
+        for (x = 0; x <= winSize.width - w; x += blockStep.width)
+        {
+            for (y = 0; y <= winSize.height - h; y += blockStep.height)
+            {
+                features.push_back(Feature(offset, x, y, t, t));
+            }
+        }
+        w = 2*t;
+        h = 4*t;
+        for (x = 0; x <= winSize.width - w; x += blockStep.width)
+        {
+            for (y = 0; y <= winSize.height - h; y += blockStep.height)
+            {
+                features.push_back(Feature(offset, x, y, t, 2*t));
+            }
+        }
+        w = 4*t;
+        h = 2*t; 
+        for (x = 0; x <= winSize.width - w; x += blockStep.width)
+        {
+            for (y = 0; y <= winSize.height - h; y += blockStep.height)
+            {     
+                features.push_back(Feature(offset, x, y, 2*t, t));
+            }
+        }
+    }
+
+    numFeatures = (int)features.size();
+}
+
+CvHOGEvaluator::Feature::Feature()
+{
+    for (int i = 0; i < N_CELLS; i++)
+    {
+        rect[i] = Rect(0, 0, 0, 0);
+    }
+}
+
+CvHOGEvaluator::Feature::Feature( int offset, int x, int y, int cellW, int cellH )
+{
+    rect[0] = Rect(x, y, cellW, cellH); //cell0
+    rect[1] = Rect(x+cellW, y, cellW, cellH); //cell1
+    rect[2] = Rect(x, y+cellH, cellW, cellH); //cell2
+    rect[3] = Rect(x+cellW, y+cellH, cellW, cellH); //cell3
+
+    for (int i = 0; i < N_CELLS; i++)
+    {
+        CV_SUM_OFFSETS(fastRect[i].p0, fastRect[i].p1, fastRect[i].p2, fastRect[i].p3, rect[i], offset);
+    }
+}
+
+void CvHOGEvaluator::Feature::write(FileStorage &fs) const
+{
+    fs << CC_RECTS << "[";
+    for( int i = 0; i < N_CELLS; i++ )
+    {
+        fs << "[:" << rect[i].x << rect[i].y << rect[i].width << rect[i].height << "]";
+    }
+    fs << "]";
+}
+
+//cell and bin idx writing
+//void CvHOGEvaluator::Feature::write(FileStorage &fs, int varIdx) const
+//{
+//    int featComponent = varIdx % (N_CELLS * N_BINS);
+//    int cellIdx = featComponent / N_BINS;
+//    int binIdx = featComponent % N_BINS;
+//
+//    fs << CC_RECTS << "[:" << rect[cellIdx].x << rect[cellIdx].y << 
+//        rect[cellIdx].width << rect[cellIdx].height << binIdx << "]";
+//}
+
+//cell[0] and featComponent idx writing. By cell[0] it's possible to recover all block
+//All block is nessesary for block normalization
+void CvHOGEvaluator::Feature::write(FileStorage &fs, int featComponentIdx) const
+{
+    fs << CC_RECT << "[:" << rect[0].x << rect[0].y << 
+        rect[0].width << rect[0].height << featComponentIdx << "]";
+}
+
+
+void CvHOGEvaluator::integralHistogram(const Mat &img, vector<Mat> &histogram, Mat &norm, int nbins) const
+{
+    CV_Assert( img.type() == CV_8U || img.type() == CV_8UC3 );
+    int x, y, binIdx;
+
+    Size gradSize(img.size());
+    Size histSize(histogram[0].size());
+    Mat grad(gradSize, CV_32F);
+    Mat qangle(gradSize, CV_8U);
+
+    AutoBuffer<int> mapbuf(gradSize.width + gradSize.height + 4);
+    int* xmap = (int*)mapbuf + 1;
+    int* ymap = xmap + gradSize.width + 2;
+
+    const int borderType = (int)BORDER_REPLICATE;
+
+    for( x = -1; x < gradSize.width + 1; x++ )
+        xmap[x] = borderInterpolate(x, gradSize.width, borderType);
+    for( y = -1; y < gradSize.height + 1; y++ )
+        ymap[y] = borderInterpolate(y, gradSize.height, borderType);
+
+    int width = gradSize.width;
+    AutoBuffer<float> _dbuf(width*4);
+    float* dbuf = _dbuf;
+    Mat Dx(1, width, CV_32F, dbuf);
+    Mat Dy(1, width, CV_32F, dbuf + width);
+    Mat Mag(1, width, CV_32F, dbuf + width*2);
+    Mat Angle(1, width, CV_32F, dbuf + width*3);
+
+    float angleScale = (float)(nbins/CV_PI);
+
+    for( y = 0; y < gradSize.height; y++ )
+    {
+        const uchar* currPtr = img.data + img.step*ymap[y];
+        const uchar* prevPtr = img.data + img.step*ymap[y-1];
+        const uchar* nextPtr = img.data + img.step*ymap[y+1];
+        float* gradPtr = (float*)grad.ptr(y);
+        uchar* qanglePtr = (uchar*)qangle.ptr(y);
+
+        for( x = 0; x < width; x++ )
+        {
+            dbuf[x] = (float)(currPtr[xmap[x+1]] - currPtr[xmap[x-1]]);
+            dbuf[width + x] = (float)(nextPtr[xmap[x]] - prevPtr[xmap[x]]);
+        }
+        cartToPolar( Dx, Dy, Mag, Angle, false );
+        for( x = 0; x < width; x++ )
+        {
+            float mag = dbuf[x+width*2];
+            float angle = dbuf[x+width*3];
+            angle = angle*angleScale - 0.5f;
+            int bidx = cvFloor(angle);
+            angle -= bidx;
+            if( bidx < 0 )
+                bidx += nbins;
+            else if( bidx >= nbins )
+                bidx -= nbins;
+
+            qanglePtr[x] = (uchar)bidx;
+            gradPtr[x] = mag;
+        }
+    }
+    integral(grad, norm, grad.depth());
+
+    float* histBuf;
+    const float* magBuf;
+    const uchar* binsBuf;
+
+    int binsStep = (int)( qangle.step / sizeof(uchar) );
+    int histStep = (int)( histogram[0].step / sizeof(float) );
+    int magStep = (int)( grad.step / sizeof(float) );
+    for( binIdx = 0; binIdx < nbins; binIdx++ )
+    {
+        histBuf = (float*)histogram[binIdx].data;
+        magBuf = (const float*)grad.data;
+        binsBuf = (const uchar*)qangle.data;
+
+        memset( histBuf, 0, histSize.width * sizeof(histBuf[0]) );
+        histBuf += histStep + 1;
+        for( y = 0; y < qangle.rows; y++ )
+        { 
+            histBuf[-1] = 0.f;
+            float strSum = 0.f;
+            for( x = 0; x < qangle.cols; x++ )
+            {
+                if( binsBuf[x] == binIdx )
+                    strSum += magBuf[x];
+                histBuf[x] = histBuf[-histStep + x] + strSum;
+            }
+            histBuf += histStep;
+            binsBuf += binsStep;
+            magBuf += magStep;
+        }
+    }
+}

modules/traincascade/HOGfeatures.h

+#ifndef _OPENCV_HOGFEATURES_H_
+#define _OPENCV_HOGFEATURES_H_
+
+#include "traincascade_features.h"
+
+//#define TEST_INTHIST_BUILD
+//#define TEST_FEAT_CALC
+
+#define N_BINS 9
+#define N_CELLS 4
+
+#define HOGF_NAME "HOGFeatureParams"
+struct CvHOGFeatureParams : public CvFeatureParams
+{
+    CvHOGFeatureParams(); 
+};
+
+class CvHOGEvaluator : public CvFeatureEvaluator
+{
+public:
+    virtual ~CvHOGEvaluator() {}
+    virtual void init(const CvFeatureParams *_featureParams,
+        int _maxSampleCount, Size _winSize );
+    virtual void setImage(const Mat& img, uchar clsLabel, int idx);    
+    virtual float operator()(int varIdx, int sampleIdx) const;
+    virtual void writeFeatures( FileStorage &fs, const Mat& featureMap ) const;
+protected:
+    virtual void generateFeatures();
+    virtual void integralHistogram(const Mat &img, vector<Mat> &histogram, Mat &norm, int nbins) const;
+    class Feature
+    {
+    public:
+        Feature();
+        Feature( int offset, int x, int y, int cellW, int cellH ); 
+        float calc( const vector<Mat> &_hists, const Mat &_normSum, size_t y, int featComponent ) const; 
+        void write( FileStorage &fs ) const;
+        void write( FileStorage &fs, int varIdx ) const;
+
+        Rect rect[N_CELLS]; //cells
+
+        struct
+        {
+            int p0, p1, p2, p3;
+        } fastRect[N_CELLS];
+    };
+    vector<Feature> features;
+
+    Mat normSum; //for nomalization calculation (L1 or L2)
+    vector<Mat> hist;
+};
+
+inline float CvHOGEvaluator::operator()(int varIdx, int sampleIdx) const
+{
+    int featureIdx = varIdx / (N_BINS * N_CELLS);
+    int componentIdx = varIdx % (N_BINS * N_CELLS);
+    //return features[featureIdx].calc( hist, sampleIdx, componentIdx); 
+    return features[featureIdx].calc( hist, normSum, sampleIdx, componentIdx); 
+}
+
+inline float CvHOGEvaluator::Feature::calc( const vector<Mat>& _hists, const Mat& _normSum, size_t y, int featComponent ) const
+{
+    float normFactor;
+    float res;
+
+    int binIdx = featComponent % N_BINS;
+    int cellIdx = featComponent / N_BINS;
+
+    const float *hist = _hists[binIdx].ptr<float>(y);
+    res = hist[fastRect[cellIdx].p0] - hist[fastRect[cellIdx].p1] - hist[fastRect[cellIdx].p2] + hist[fastRect[cellIdx].p3];
+
+    const float *normSum = _normSum.ptr<float>(y);
+    normFactor = (float)(normSum[fastRect[0].p0] - normSum[fastRect[1].p1] - normSum[fastRect[2].p2] + normSum[fastRect[3].p3]);
+    res = (res > 0.001f) ? ( res / (normFactor + 0.001f) ) : 0.f; //for cutting negative values, which apper due to floating precision
+
+    return res;
+}
+
+#endif // _OPENCV_HOGFEATURES_H_

modules/traincascade/boost.cpp

@@ -233,7 +233,7 @@ void CvCascadeBoostTrainData::setData( const CvFeatureEvaluator* _featureEvaluat
 	if( _precalcValBufSize < 0 || _precalcIdxBufSize < 0)
         CV_Error( CV_StsOutOfRange, "_numPrecalcVal and _numPrecalcIdx must be positive or 0" );
 
-	var_count = var_all = featureEvaluator->getNumFeatures();
+	var_count = var_all = featureEvaluator->getNumFeatures() * featureEvaluator->getFeatureSize();
     sample_count = _numSamples;
     
     is_buf_16u = false;     

modules/traincascade/cascadeclassifier.cpp

@@ -4,7 +4,7 @@
 using namespace std;
 
 static const char* stageTypes[] = { CC_BOOST };
-static const char* featureTypes[] = { CC_HAAR, CC_LBP };
+static const char* featureTypes[] = { CC_HAAR, CC_LBP, CC_HOG };
 
 CvCascadeParams::CvCascadeParams() : stageType( defaultStageType ), 
     featureType( defaultFeatureType ), winSize( cvSize(24, 24) )
@@ -25,7 +25,9 @@ void CvCascadeParams::write( FileStorage &fs ) const
     CV_Assert( !stageTypeStr.empty() );
     fs << CC_STAGE_TYPE << stageTypeStr;
     String featureTypeStr = featureType == CvFeatureParams::HAAR ? CC_HAAR :
-                            featureType == CvFeatureParams::LBP ? CC_LBP : 0;
+                            featureType == CvFeatureParams::LBP ? CC_LBP : 
+                            featureType == CvFeatureParams::HOG ? CC_HOG :
+                            0;
     CV_Assert( !stageTypeStr.empty() );
     fs << CC_FEATURE_TYPE << featureTypeStr;
     fs << CC_HEIGHT << winSize.height;
@@ -49,7 +51,9 @@ bool CvCascadeParams::read( const FileNode &node )
         return false;
     rnode >> featureTypeStr;
     featureType = !featureTypeStr.compare( CC_HAAR ) ? CvFeatureParams::HAAR :
-                  !featureTypeStr.compare( CC_LBP ) ? CvFeatureParams::LBP : -1;
+                  !featureTypeStr.compare( CC_LBP ) ? CvFeatureParams::LBP : 
+                  !featureTypeStr.compare( CC_HOG ) ? CvFeatureParams::HOG :
+                  -1;
     if (featureType == -1)
         return false;
     node[CC_HEIGHT] >> winSize.height;
@@ -509,14 +513,15 @@ bool CvCascadeClassifier::load( const String cascadeDirName )
 
 void CvCascadeClassifier::getUsedFeaturesIdxMap( Mat& featureMap )
 {
-    featureMap.create( 1, featureEvaluator->getNumFeatures(), CV_32SC1 );
+    int varCount = featureEvaluator->getNumFeatures() * featureEvaluator->getFeatureSize();
+    featureMap.create( 1, varCount, CV_32SC1 );
     featureMap.setTo(Scalar(-1));
     
     for( vector< Ptr<CvCascadeBoost> >::const_iterator it = stageClassifiers.begin();
         it != stageClassifiers.end(); it++ )
         ((CvCascadeBoost*)((Ptr<CvCascadeBoost>)(*it)))->markUsedFeaturesInMap( featureMap );
     
-    for( int fi = 0, idx = 0; fi < featureEvaluator->getNumFeatures(); fi++ )
+    for( int fi = 0, idx = 0; fi < varCount; fi++ )
         if ( featureMap.at<int>(0, fi) >= 0 )
             featureMap.ptr<int>(0)[fi] = idx++;
 }

modules/traincascade/cascadeclassifier.h

@@ -5,6 +5,7 @@
 #include "traincascade_features.h"
 #include "haarfeatures.h"
 #include "lbpfeatures.h"
+#include "HOGfeatures.h" //new
 #include "boost.h"
 #include "cv.h"
 #include "cxcore.h"
@@ -41,6 +42,7 @@
 #define CC_FEATURES       FEATURES
 #define CC_FEATURE_PARAMS "featureParams"
 #define CC_MAX_CAT_COUNT  "maxCatCount"
+#define CC_FEATURE_SIZE   "featSize"
 
 #define CC_HAAR        "HAAR"
 #define CC_MODE        "mode"
@@ -53,6 +55,8 @@
 #define CC_LBP  "LBP"
 #define CC_RECT "rect"
 
+#define CC_HOG "HOG"
+
 #ifdef _WIN32
 #define TIME( arg ) (((double) clock()) / CLOCKS_PER_SEC)
 #else

modules/traincascade/features.cpp

@@ -26,7 +26,7 @@ bool CvParams::scanAttr( const String prmName, const String val ) { return false
 
 //---------------------------- FeatureParams --------------------------------------
 
-CvFeatureParams::CvFeatureParams() : maxCatCount( 0 )
+CvFeatureParams::CvFeatureParams() : maxCatCount( 0 ), featSize( 1 )
 {
     name = CC_FEATURE_PARAMS; 
 }
@@ -34,11 +34,13 @@ CvFeatureParams::CvFeatureParams() : maxCatCount( 0 )
 void CvFeatureParams::init( const CvFeatureParams& fp )
 {
     maxCatCount = fp.maxCatCount;
+    featSize = fp.featSize;
 }
 
 void CvFeatureParams::write( FileStorage &fs ) const
 {
     fs << CC_MAX_CAT_COUNT << maxCatCount;
+    fs << CC_FEATURE_SIZE << featSize;
 }
 
 bool CvFeatureParams::read( const FileNode &node )
@@ -46,13 +48,16 @@ bool CvFeatureParams::read( const FileNode &node )
     if ( node.empty() )
         return false;
     maxCatCount = node[CC_MAX_CAT_COUNT];
-    return maxCatCount >= 0;
+    featSize = node[CC_FEATURE_SIZE];
+    return ( maxCatCount >= 0 && featSize >= 1 );
 }
 
 Ptr<CvFeatureParams> CvFeatureParams::create( int featureType )
 {
     return featureType == HAAR ? Ptr<CvFeatureParams>(new CvHaarFeatureParams) :
-        featureType == LBP ? Ptr<CvFeatureParams>(new CvLBPFeatureParams) : Ptr<CvFeatureParams>();
+        featureType == LBP ? Ptr<CvFeatureParams>(new CvLBPFeatureParams) : 
+        featureType == HOG ? Ptr<CvFeatureParams>(new CvHOGFeatureParams) :
+        Ptr<CvFeatureParams>();
 }
 
 //------------------------------------- FeatureEvaluator ---------------------------------------
@@ -79,5 +84,7 @@ void CvFeatureEvaluator::setImage(const Mat &img, uchar clsLabel, int idx)
 Ptr<CvFeatureEvaluator> CvFeatureEvaluator::create(int type)
 {
     return type == CvFeatureParams::HAAR ? Ptr<CvFeatureEvaluator>(new CvHaarEvaluator) :
-        type == CvFeatureParams::LBP ? Ptr<CvFeatureEvaluator>(new CvLBPEvaluator) : Ptr<CvFeatureEvaluator>();
+        type == CvFeatureParams::LBP ? Ptr<CvFeatureEvaluator>(new CvLBPEvaluator) : 
+        type == CvFeatureParams::HOG ? Ptr<CvFeatureEvaluator>(new CvHOGEvaluator) :
+        Ptr<CvFeatureEvaluator>();
 }

modules/traincascade/traincascade.cpp

@@ -17,8 +17,9 @@ int main( int argc, char* argv[] )
     CvCascadeParams cascadeParams;
     CvCascadeBoostParams stageParams;
     Ptr<CvFeatureParams> featureParams[] = { Ptr<CvFeatureParams>(new CvHaarFeatureParams),
-                                             Ptr<CvFeatureParams>(new CvLBPFeatureParams)
-                                           }; 
+                                             Ptr<CvFeatureParams>(new CvLBPFeatureParams), 
+                                             Ptr<CvFeatureParams>(new CvHOGFeatureParams)
+                                           };
     int fc = sizeof(featureParams)/sizeof(featureParams[0]);
     if( argc == 1 )
     {

modules/traincascade/traincascade_features.h

@@ -65,13 +65,14 @@ public:
 class CvFeatureParams : public CvParams
 {
 public:
-    enum { HAAR = 0, LBP = 1 };
+    enum { HAAR = 0, LBP = 1, HOG = 2 };
     CvFeatureParams();
     virtual void init( const CvFeatureParams& fp );
     virtual void write( FileStorage &fs ) const;
     virtual bool read( const FileNode &node );
     static Ptr<CvFeatureParams> create( int featureType );
     int maxCatCount; // 0 in case of numerical features
+    int featSize; // 1 in case of simple features (HAAR, LBP) and N_BINS(9)*N_CELLS(4) in case of Dalal's HOG features
 };
 
 class CvFeatureEvaluator
@@ -87,6 +88,7 @@ public:
 
     int getNumFeatures() const { return numFeatures; }
     int getMaxCatCount() const { return featureParams->maxCatCount; }
+    int getFeatureSize() const { return featureParams->featSize; }
     const Mat& getCls() const { return cls; }
     float getCls(int si) const { return cls.at<float>(si, 0); }
 protected: