ffmpeg - generate moov atom

Question

I am currently recording video with blackmagic's prorecorder. I transcode video on-the-fly to mp4 video container with ffmpeg. Duration is unknown as I'm transcoding .ts that prorecorder is outputing to named pipe.

My goal is to I try to play this file with browser, while stream is still beeing recorded - Playback is great, but problem is that when I open file, duration is defined to current recording time.

So, question is - I would like to generate "fake" moov atom for duration of fe. 8 hours with ffmpeg, and then start recording mp4 file as I'm already doing. How could I do this?

Documentation that I checked and I think it's relevant - https://ffmpeg.org/ffmpeg-formats.html#MOV_002fMP4_002fISMV I also saw this on stack: Is it possible to fake a (mp4) moov atom?

Answer 1

I had a similar problem and only discovered it after encoding nearly 2000 videos. Instead of starting over, I used this command to insert the moov atom:

/usr/bin/ffmpeg -i ./input.mp4 -c:v copy -movflags faststart -strict -2 ./output.mp4