If your file is severely broken (e.g., recorded on a phone that died), it may lack a "header". Tools like use a healthy file to fix the broken one. healthy video
ffmpeg -err_detect ignore_err -i input.mp4 -c copy output.mp4 nippy user since 2015 mp4 fix
If the original Nippy link is dead, try pasting the URL into the Internet Archive If your file is severely broken (e
Always run a SHA-256 check after downloading old files to ensure they weren't corrupted during transit. recorded on a phone that died)
: This is a common method to fix header issues without re-encoding the actual video stream.
In my experience, most "broken" MP4s are just suffering from bad header data. Because