Re: [Encode2mpeg-users] quality options in mpeg mode

[Giacomo C. <enc...@us...>]

On Wed, Mar 01, 2006 at 05:40:20PM -0400, Osmany Guirola Cruz wrote:
> Hi
>    I am using mpeg mode to do (s)vcd and i am using -encode 4:4:1  i use
> *:4:* to get quality but i do a ps aux | grep mencoder and saw this
> options...
> :mbd=2:mv0:precmp=6:cmp=6:subcmp=6 
> i want to know why not include other options like v4mv , dia=? , dc=?
> or if with this option it's "OK" to get a good quality film...... 
> 
> Thanks 
> Osmany

The quality option I use are the one that gave me a very high PSNR.
The test were done for DVD encoding, so may be the options are
not the best for VCD/SVCD.
Coming back to your question:

v4mv is valid only for mpeg4 and it is used in avi mode, it does not 
work for mpeg1/2.

dc!=8 also is not valid for mpeg1 and it makes sense for mpeg2 only
with high bit rate. For that reason is disabled for VCD/SVCD, but it
is enabled for DVD.

I found also that dia results may vary with differents source video, 
so no specific dia option were chosen.

So, to fully answer your question, -encode n:4:i will give 
the better quality compared to the other three modes, but
surely it would be possible to find, for EACH MOVIE you want
to encode, a specific set of options that will give a higher PSNR.

The one I choose should be a good compromise.
If somebody can provide me a better combination, I will use it.

It would also be good to have some -encode n:5:i
better suited for amine. Unfortunately I have neved done
anime encoding and therefore I don't know what to use.

Giacomo

P.S. In order to see the options used by mencoder add the 
option -debug and check the log file.