[FFmpeg-user] Can I repair with ffmpeg a mp4 file where the moov atom is not found ?

[Rob Hallam]

On 27 November 2017 at 22:37, Steve Boyer <steveboyer85 at gmail.com> wrote:
> Yes, it is possible. The linux program is untrunc, and you might have to
> compile it yourself. http://vcg.isti.cnr.it/~ponchio/untrunc.php.
> Essentially, it reconstructs it the best it can using the information to go
> by off of another MP4 file - it works best if you have a working MP4 file
> from the same system/settings.

I suddenly had a use for this, so thank you Steve (and Sandro for
asking the question). The link included 404s, but the project can be
found on GitHub: https://github.com/ponchio/untrunc (with the note
that there is an Arch AUR package!)

(In case anyone is interested: I have been uploading files to Youtube,
and unexpectedly got the error "Upload failed: Can't process file".
For some reason, a couple of the GoPro clips out of the dozen or so I
had been concat-demuxing for upload somehow lost their moov atom
according to ffprobe. Go figure. Since I have similarly-produced
files, untrunc might work. Sadly, I was hit by it's issue #30:
https://github.com/ponchio/untrunc/issues/30 Hey ho.)

Cheers,
Rob