[mythtv-users] FFMPeg Commercial cutting puts audio out of sync

[Justin Alcorn]

On Sat, Sep 13, 2014 at 5:21 AM, Mike Perkins
<mikep at randomtraveller.org.uk> wrote:
>> After hours of reading posts and playing with settings, I've cot a
>> couple of theories.
>>
>> A) the video is cutting on 'key frames', not at exactly the time I say
>> to cut, but the audio cuts at the exact mark
>> B) The video being in variable bitrate throws off the cutting
>>
>> But I'm not sure how to solve either of these problems.
>>
> [snip]
>>
>>
> The most obvious thing to say is that you should make sure your cuts are all
> on keyframes. This should reduce any difference between audio and video to
> the minimum.
>
> If you don't make cuts on keyframes then the video processor has to try and
> bridge data that really belongs to two different scenes and adjust
> dynamically, which can look terrible on-screen. Keyframes is the way to go.


That fits with one of my theories so the question is - how do I get
ffmpeg to cut at the keyframe closest to the time I specify?
--
Justin B. Alcorn
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