opencv色彩空间转换及通道操作

  int main()  {  Mat M=imread("21.jpg",1);  Mat dst,dst2;  cvtColor(M,dst,CV_RGB2HSV);  imshow("src",M);  vector<Mat> hsvChannels;  split(dst,hsvChannels);  imshow("v",hsvChannels[2]);  for(int i=0;i<hsvChannels[2].rows;i++)  {  uchar*pt=(uchar*)hsvChannels[2].ptr(i);  for(int j=0;j<hsvChannels[2].cols;j++)  {  pt[j]=(uchar)(log(1.0+pt[j])*255/log(256.0));  }  }  imshow("v2",hsvChannels[2]);  merge(hsvChannels,dst);  imshow("dst",dst);  cvtColor(dst,dst2,CV_HSV2RGB);  imshow("dst2",dst2);  cv::waitKey(0);  return 0;  }