[FFmpeg-user] Comparing audio to sync video

[Michael Koch]

> I have two video cameras recording an event 30 minutes long. I hit 
> start on the two cameras at different times. I would like to figure 
> out a command-line script that can basically diff the audio to figure 
> out the difference between the start times and align the videos. The 
> audio won't be exactly identical as they are two different cameras, 
> different mics, different locations, but they are both recording an 
> interview, so the audio should be able to be synced. Any ideas?

I think to automatically find the best-fit audio delay between the two 
tracks you would need to calculate a cross correlation of the two audio 
tracks. As far as I know this doesn't exist in ffmpeg. But it would be 
nice to have.

Michael