B1339.mp4 -

: The VP9 encoder expects the --frame-parallel setting to be a strictly boolean value (0 or 1). Setting it to other values (like 16) has been known to cause unexpected encoder behavior or invalid bitstreams .

If you are simply trying to play or fix an MP4 file with this name, here are the most helpful troubleshooting steps: b1339.mp4

If you are dealing with a video file that is crashing or failing during encoding, it may be related to in the libvpx (VP9) project. : The VP9 encoder expects the --frame-parallel setting