message: videoio: fix lifetime management of data of input frames
diff: @@ -223,7 +223,7 @@ public:
  if (!ffmpegCapture ||
  !icvRetrieveFrame_FFMPEG_p(ffmpegCapture, &data, &step, &width, &height, &cn))
  return false;
  - frame.assign(cv::Mat(height, width, CV_MAKETYPE(CV_8U, cn), data, step));
  + cv::Mat(height, width, CV_MAKETYPE(CV_8U, cn), data, step).copyTo(frame);
  return true;
  }
  virtual bool open( const cv::String& filename )
  