[FFmpeg-user] -istoffset and -vcodec copy

Jonathan Addleman jono at redowl.ca
Mon Nov 28 16:56:58 CET 2011

On 11-11-28 05:16 AM, Carl Eugen Hoyos wrote:
> Jonathan Addleman<jono<at>  redowl.ca>  writes:
>>  >>   With the 'veryslow' preset, the results are abysmal - nasty artifacts
>>  >>   everywhere. Utterly unusable.
>>  >
>>  >  You have to either define a low constant quantiser or a target bitrate.
>>  Even with -qscale 1, it looked awful. (I assume that's what you mean?)
> (Command line and complete, uncut output missing.)
> -qscale 2 works fine with -vcodec mpeg2video and -vcodec mpeg4, I suspect you
> have to use a x264 option for -vcodec libx264.

Ah, I didn't realize these options didn't apply to the libx264 codec. 
It's awfully complicated! I'm going to do some more reading, and try to 
get the newer version of ffmpeg compiled to see if -vcodec copy works there.

In the meantime, mpeg4 with qscale 1 seems to give acceptable quality, 
though the file size is over twice as big.

Jon-o Addleman - http://www.redowl.ca

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