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Hitching and Smoothness problem with videocapture::read

So I'm having a problem with the VideoCapture::read function.

When I run this function:

void Camera::DoFrame( cv::Mat& im, vector<Location> &locations)
{
if(!TheVideoCapturer.isOpened())
return;

TheVideoCapturer >> im;

locations = processFrame(im);
//imshow("video", im);
//cv::waitKey(30);
}


The average time taken is 33 milliseconds, Most of that time is taken up by the TheVideoCapturer >> im; This is fine as that is a good frame rate, however it has periods where the time will spike up to 250ms. This obviously produces problems with the smoothness of my video, one which I wanted to fix. I think it also might be related to the video skipping occcasionly.

After suspecting my camera and another of other issues, I found that by uncommenting 2 lines in the above sample of code, I could get the video to out put much more consistantly, with the longest time the read function takes is 30ms, though the average is 2ms. This is more like what i would expect as a frame rate. It also seems to relieve my problem of the video being not smooth enough. The only problem with this is that I neither want to output a video from my camera, or wait 30ms if I can help it. Is there something I misunderstand about the read method? Has anyone expereienced something similar?

I am using opencv version 2.4.5, I experience the same bug in both visual studio and mingw, and get the same problem on both a logitech pro 9000 and a logitech pro c910

Thanks