[MPlayer-users] Re: encoding quality - bpp, resolution, quants and quality

[D Richard Felker III]

On Thu, Sep 11, 2003 at 07:44:31PM +0200, HR wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> 
> No statements from others included - this is a followup.
> 
> Encoding a movie with 
> 
> -lavcopts
> vcodec=mpeg4:keyint=125:vbitrate=1802:vhq:v4mv:precmp=2:cmp=2:subcmp=2
> 
> counting the quants with a simple script I made, I get
> 
> /usr/local/bin/countquant: q=1 0.7%
> /usr/local/bin/countquant: q=2 40.1%
> /usr/local/bin/countquant: q=3 39.9%
> /usr/local/bin/countquant: q=4 8.1%
> /usr/local/bin/countquant: q=5 5.0%
> /usr/local/bin/countquant: q=6 3.5%
> /usr/local/bin/countquant: q=7 1.6%
> /usr/local/bin/countquant: q=8 0.4%
> /usr/local/bin/countquant: q=9 0.2%
> /usr/local/bin/countquant: q=15 0.3%
> /usr/local/bin/countquant: q=16 0.1%
> /usr/local/bin/countquant: q=25 0.5%
> /usr/local/bin/countquant: q=31 0.2%
> (dont mind if it doesnt add up exactly, rounding errors are surely
> plenty)
> 
> Does this mean I should decrease the resolution? If I understand other

No. Lower resolution will hurt the quality MUCH more than q=3 frames.
Even constant q=3 will look very good at high resolution (since the
artifacts are on very small scale). IMO the above numbers are the
result of a very good encode.

Rich