How to solve the issue of high memory usage when writing too many frames using FFmpeg as the API Backend for OpenCV 4.7 VideoWriter on Linux[CANCELED]

C++
1

I encountered a issue of high memory usage when writing too many frames using FFmpeg as the API Backend for OpenCV 4.7 VideoWriter on Linux, The pseudo code is as follows:

    cv::VideoWriter writer(video_path, video_fourcc, video_fps, video_size);
    int32_t frame_nums = 10000;
    for (int32_t i = 0; i < frame_nums; ++i) {
        cv::Mat frame;

        // some operations
        // ...

        writer.write(frame);
        frame.release();
    }
    writer.release();

As the number of frames written increases, the memory usage becomes larger and larger, and I can not reduce the memory usage.

I try to release the frame after writing it but it does not work, and I do not find anything like flush or any way to set the buffer size of VideoWriter.

How to solve it?

2

that pseudo code contains no issues.

you’ll need to present actual code, a MRE, that is debuggable. also all relevant information you have about the environment.

and especially quantify “high memory usage”/“larger and larger” in space and time.

3

Thanks for your reply. I was misled before, and I find the real reason of high memory now, it’s not opencv problem.