QT video write from images (cv::Mat) problem

RahibeMeryem

Hi,

I am using thread and signal slot mechanism in my opencv object detection framework.

I decide to write frames as video (mp4 or mjpg) to a file.

I opened :

video = new VideoWriter;
cv::VideoWriter video ("/data/outcpp.avi",CV_FOURCC('M','J','P','G'),25, Size(1280,720));
..
..
    video->write(frame);

frame is coming from:

connect(worker , &Worker::frameChanged , recorder , &Vrecorder::recording);

it is creating file outcpp.avi and the size stuct at 4kb. It is not writing the video.

Same code is working as pure c++ without QT signal slot mechanism.

Any suggestion ?

Or any experince to write video from signalling with opencv or ffmpeg ?

Which one is preferable ?

SGaist

Hi,

You should show the complete code you are using. In what you posted, you seem to have some pointer to a VideoWriter, then a local cv::VideoWriter with the same name, then writing through the first object.