1. 颜色空间变换 RGB--> HSV

   cvCvtColor(src,dst,CV_RGB2HSV);

2. 颜色通道分开

   cvCvtPixToPlane(src,H,S,V,0); //或者用 cvSplit(src,h,s,v)

3. 建立、计算、访问直方图

   CvHistogram* hist;

   {

   int hist_size[] = {h_bins,s_bins, v_bins};

   float h_ranges[] = {0,255};

   float s_ranges[] = {0,255};

   float v_ranges[] = {0,255};

   float* ranges[] = {h_ranges, s_ranges, v_ranges};

   hist = cvCreateHist(3,hist_size,CV_HIST_ARRAY,ranges,1);

   }

   cvCalcHist(HSV,hist,0,0);

   int bin_val = cvQueryHistValue_3D(hist,h,s,v);

4. opencv中的HSV空间三个通道的数值范围被转化到了【0,255】

5.