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Hi :) I would like to convert a grayscale avi to images. I use the following code but the produced images are all black. When I use a colour avi, it does work perfect but it doesn't work for grayscale avi. How can I solve this problem? Thanks for your help. Best; Beldachi

int main (int argc, char **argv) { if (argc !=2) { std::cout << "USE: " << argv[0] << " <video-filename>" << std::endl; return -1; }

//Open the video that you pass from the command line cv::VideoCapture cap(argv[1]); if (!cap.isOpened()) { std::cerr << "ERROR: Could not open video " << argv[1] << std::endl; return -1; }

int frame_count = 0; bool should_stop = false;

while(!should_stop) { cv::Mat frame; cap >> frame; //get a new frame from the video if (frame.empty()) { should_stop = true; //we arrived to the end of the video continue; }

char filename[128];
sprintf(filename, "frame_%06d.jpg", frame_count);  
frame.convertTo(frame,CV_8U); 
cv::imwrite(filename, frame);
frame_count++;

}

return 0; }

Hi :) I would like to convert a grayscale avi to images. I use the following code but the produced images are all black. When I use a colour avi, it does work perfect but it doesn't work for grayscale avi. How can I solve this problem? Thanks for your help. Best; Beldachi

int main (int argc, char **argv)
{
  if (argc !=2)
  { 
    std::cout << "USE: " << argv[0] << " <video-filename>" << std::endl;
    return -1;
  }
 
}

  //Open the video that you pass from the command line
  cv::VideoCapture cap(argv[1]);
  if (!cap.isOpened())
  {
    std::cerr << "ERROR: Could not open video " << argv[1] << std::endl;
    return -1;
  }
 
}

  int frame_count = 0;
  bool should_stop = false;
 
false;

  while(!should_stop)
  {
    cv::Mat frame;
    cap >> frame; //get a new frame from the video
    if (frame.empty())
    {
      should_stop = true; //we arrived to the end of the video
      continue;
    }
 
}

    char filename[128];
 sprintf(filename, "frame_%06d.jpg", frame_count);  
 frame.convertTo(frame,CV_8U); 
 cv::imwrite(filename, frame);
 frame_count++;
  }

  return 0;
}
  
}
 
return 0;
}