[FFmpeg-user] [Bulk] Re: ProRes Quicktimes with audio not playing back reliably

[Bob Maple]

I'm still trying to figure this one out and started playing with ffprobe 
tonight.

One thing I'm seeing is that the way ffmpeg is muxing the audio and 
video together seems to be quite fragmented compared to a "real" ProRes 
file made on a Mac (live capture in Final Cut.)

I did an an 'ffprobe -show_packets' on both a ProRes/s16le file encoded 
by ffmpeg and one encoded by Final Cut, and then did a 'grep codec_type' 
on the output to show me the audio/video packets as they were encountered.

For the FCP file I get what seems to be a regular pattern of 47 audio 
packets followed by 30 video packets.

For the ffmpeg encoded file, I get a more irregular and vastly shorter 
interleave.. AA V AA V A V AA V A V AA V A V AA V AA V A V AA V A V AA V 
etc.

Not sure if I'm barking up the wrong tree but I wonder if this very 
tight interleaving is what could be throwing Quicktime off its axis?

By the way I didn't mention in my original post that this isn't just 
Quicktime Player having problems playing back (I generally despise 
Quicktime but Apple is particularly crap at writing Windows software) 
but any realtime apps that use Quicktime IO...  for instance if I link 
to the movies in Avid Media Composer, I get stuttering and dropped frame 
indications there as well.


|  Bob Maple