Vid_20221215_105814_430.mp4.mkv

MKV files can store rich metadata that MP4s cannot, such as "Writing Application" (e.g., mkvmerge v70.0.0 ) or "Writing Library" (e.g., libebml ). This reveals which software handled the file after it left the phone.

Use the command ffprobe -show_packets VID_20221215_105814_430.mp4.mkv to see if there are any dropped frames or timestamp gaps, which indicate the "health" of the video stream. VID_20221215_105814_430.mp4.mkv

Tools like MKVToolNix often wrap MP4s into MKV to edit without re-encoding. MKV files can store rich metadata that MP4s