[FFmpeg-user] Worse quality than mencoder [SOLVED]
n32 at email.cz
Wed Nov 26 14:36:52 CET 2014
On 2014-11-26 12:30, Moritz Barsnick wrote:
> Are you absolutely sure?
I'm sorry, they're the same only for the second pass: that was the problem.
> You're doing two-pass, right? If that is why these logs each contain
> two outputs from the encoders, then you're doing something
> significantly wrong:
> mencoder.txt:x264 [info]: profile Main, level 3.0
> mencoder.txt:x264 [info]: profile High, level 4.0
> ffmpeg.txt:[libx264 @ 0x63c9c0] profile Main, level 4.0
> ffmpeg.txt:[libx264 @ 0x63c9c0] profile High, level 4.0
Level was not the problem.
> The libx264 settings from the first pass and second pass differ
> significantly from each other - and in a different manner in ffmpeg and
> mencoder. Only the second pass settings seem identical, which may be
> why you see the same embedded in the file.
Yes, you're right, that was the problem. The encoders set some parameters
for quicker first pass (I knew that), but what I didn't know that ffmpeg doesn't
set fast_pskip=1 and ref=1 while mencoder does.
> AFAIU you need to use identical codec options in both passes, and it
> seems you're not doing that. That _may_ be the cause for your
In fact, it is. I compared the achieved quality after changing the two mentioned
parameters and it looks almost the same now. So marking as SOLVED. Thanks
everybody for your precious help.
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