OT - sync & h.264 files
by Paul Dougherty on Apr 6, 2015 at 1:28:35 am
I was giving a bunch of funky* h.264 mov interview files with different frame rates, some as low as 19fps.
Playback (lip)sync seemed intermittent, soft & prone to drift. Except for one file that was *way bad* I was able to edit and output good sync HQ versions in Premiere CC 2014. However like a monster that would not die, if I then took these HQ outputs - let's call them Masters - and went to make small lo-rez copies (derivatives) sync would be noticeably off. This was the case with both Compressor 3.5 and Adobe Media Encoder CC. (Think I tried to output both mov & mp4 files)
The general question I want to ask is… Are h.264 or mp4 files any more prone to lip-sync problems than any other format/codec? (like ProRes?)
Second I want to ask about the default export mode in Premiere, it would appears to be h.264 Match Source - which generally seems to like a attractive option. But I notice when I output the mp4 I see it making 2 files, an audio aac & video m4v (that then get joined in a single file container). I notice that this does not happen when outputting a Qt mov (I only see one file during export). Could this have bearing on why my exports as "h.264 Match Source" have the sync problems with copies made from them?
*I posted earlier and there was mention of an image stabilizer causing the different frame rates.
Sorry but this material from the client with the changing frame rates was such a bear and kicked up so many issues… I had to post this one last question.