opencv 写视频错误

18063363651

使用opencv 写入视频出错

cv::VideoWriter writer;
writer.open("1.mp4", cv::VideoWriter::fourcc('m', 'p', '4', 'v'), saveFps, cv::Size(saveW, saveH), false);
//writer.isOpened() 返回 0
并且有下面提示：

[mpeg4_v4l2m2m @ 0x7fa0094060] Could not find a valid device[mpeg4_v4l2m2m @ 0x7fa0094060] can't configure encoderCould not open codec 'mpeg4_v4l2m2m': Unspecified error[ WARN:1] global ../modules/videoio/src/cap_gstreamer.cpp (1580) open OpenCV | GStreamer warning: cannot link elements