[MEncoder-users] Flashvideo for YouTube using mencoder

[Reimar Döffinger]

On Fri, Feb 22, 2008 at 09:46:47PM +0100, Ben wrote:
> On Fri, Feb 22, 2008 at 7:36 PM, Reimar Döffinger
> <Reimar.Doeffinger at stud.uni-karlsruhe.de> wrote:
> >  No. Just try it: encode with keyint=1:vqscale=31 and compare it to
> >  keyint=50000:vqscale=1:vqmin=1
> 
> Like I wrote before, even if in this case the bigger keyint would
> yield higher quality,
> it's not according to the norm. Videoquality is not higher in between keyframes,
> it is highest AT the keyframes.

I have the feeling you are completely confused about the concepts of
video encoding.
_If_, for a specific encoder (and this will depend on the encoder) video
quality is higher at the keyframes this means
1) if it is more than marginal, your encoder sucks because you will notice
every keyframe by the sudden increase in quality, i.e. the video will
have a "pulse" effect which everyone who has seen it (e.g. due to bugs
in early ffmpeg vc-1 decoders) is bot _very_ visible and _very_ annoying
2) this is then only so because the encoder throws bits at the keyframes
like crazy, and in case of libavcodec that is usually because you have
told it to do so (possibly by using the default settings), see the
vb/vi_qoffset/qfactor.