Looks good! I didn’t know if people were still interested in this, thanks for the update. If you want to send in a patch that’d be cool, I’m sure it’d be helpful to others. Thanks!

// ADD After for loop
cvReleaseImage(&frame); // cloned image

// reduces cloning/creating & fixes leak
//a helper function to convert from color to gray
IplImage* convert_grayscale(IplImage *img)
{
IplImage *gray_image, *gray_img0;

//check image is it gray or not if nor convert it to the gray
if(img->nChannels!=1)
{
//convert original image to gray_scale image
gray_image = cvCreateImage(cvSize( img->width, img->height), 8, 1 );
cvCvtColor(img, gray_image, CV_RGB2GRAY );
}
else
{
gray_image = cvCloneImage(img);
}

return gray_image;
}