[FFmpeg-user] problem with audio/video sync after conversion

[Arlo Leach]

Hello,

> Imo, QuickTime is the relevant application for your use case, 
> you could try to change length, resolution, audio bitrate, audio 
> rate, x264 options and especially audio encoder to find out what 
> makes your player fail.

I experimented with some different audio sample resolutions and bit rates. I also tried an -acodec copy to copy the audio without converting it, but got the same result.

I next tried converting to FLV video instead of MP4/H264, and that worked fine, even while still using AAC audio. This leaves my x264 settings to experiment with. I'm using a preset with the following contents:

coder=1
flags=+loop
cmp=+chroma
partitions=+parti8x8+parti4x4+partp8x8+partb8x8
me_method=hex
subq=7
me_range=16
g=250
keyint_min=25
sc_threshold=40
i_qfactor=0.71
b_strategy=1
qcomp=0.6
qmin=10
qmax=51
qdiff=4
bf=3
refs=3
directpred=1
trellis=1
flags2=+bpyramid+mixed_refs+wpred+dct8x8+fastpskip
wpredp=2

Can someone tell me which of these settings are most likely to affect audio sync in the Flash player, and what I might try changing them to?

Actually since my problem doesn't occur with all source videos, perhaps the problem is not one of the settings that's in the preset, but an additional setting that should be there. I'm thinking some source videos already have a necessary property and others don't, so I need to add that in case it's not already there.

Thanks,
-Arlo

_______________________________

Arlo Leach
http://arlomedia.com