[FFmpeg-user] Syncing clips based on audio waveform?

[Dave Rice]

On Mar 1, 2013, at 6:00 PM, Pavel Koshevoy <pkoshevoy at gmail.com> wrote:

> On 3/1/2013 3:17 PM, Pavel Koshevoy wrote:
>> On 3/1/2013 9:38 AM, Arthur Wait wrote:
>>> Hi all,
>>> 
>>> This is coming from out of left field I imagine, but I'm wondering if
>>> anyone knows of a filter (or chain of filters) which would allow me to
>>> align/sync two video clips based on matches in their audio waveforms.
>>> 
>>> I'm shooting events with multiple cameras and would like to either trim the
>>> clips to a precise, matching starting frame or generate a metadata "offset"
>>> marker indicating how far off one clip is from the other in time. Then I
>>> can trim the clips to match.
>>> 
>>> Is this possible in ffmpeg (or anywhere else for that matter!)?
>> 
>> 
>> I don't know if there is anything in ffmpeg that would accomplish what you need right now, and I doubt implementing it as a filter is very practical.  It could be implemented as a separate utility -- give it a reference file and another file and it spits out time offset of the second file relative to the reference file (if it can find a correlation).
> 
> Now that I think about it, this feature probably should be implemented in ffprobe.

+1 for that.
Dave Rice