[MPlayer-users] Re: Encoding "dark" movies

[Rémi Guyomarch <rguyom@xxxxxxxxx>]

On Sat, Dec 07, 2002 at 11:31:40AM +0100, Stephan André Schmidt wrote:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> Hello,
> 
> when encoding "dark" movies like "Panic Room" or "From Hell", the assumed 
> bitrate to end up in a divx about 1400 MB, i.e. about 1390 for "From 
> Hell", does end in an avi of around only 900 MB (3-pass encoding).

Libavcodec is simply too powerful.

> Giving 
> the bitrate of about 1200 to mencoder does not make any difference to the 
> file size of the avi; it is also around 900 MB. Are there any special 
> filters or options to libavcodec handling this kind of "dark" movies, so 
> that the "calculated" avi size will be reached after encoding?

dd if=/dev/urandom bs=1m count=500 >> your_900mb.avi

> nice -+19 mencoder -dvd 1 -dvd-device $DVD_DEV -oac copy -o from_hell.avi 
> -ovc lavc -lavcopts 
> vcodec=mpeg4:vbitrate=1386:vhq:vpass=2:vqmin=2:vqmax=31 -vop 
> scale=640:352,crop=720:434:0:74

Every single frame is already encoded at the minimum quantizer (2) and
libavcodec simply can't produce more bits.

Hints (choose one or more and retry) :
- use a sharper rescaling method, like -sws 9 or 10
- use mpeg quantizers
- increase encoding resolution, try scale=704:304,crop=704:432:8:75
  (only scale Y axis)
- go for one CD

-- 
Rémi