[MPlayer-dev-eng] [PATCH] DCT decimation on P-Frames

[Guillaume POIRIER]

Hi,

On 4/22/06, Dominik 'Rathann' Mierzejewski <dominik at rangers.eu.org> wrote:
> On Saturday, 22 April 2006 at 10:05, Guillaume POIRIER wrote:
> [...]
> > +.B (no)dct_decimate
> > +Eliminate dct blocks on P-frames containing only a small single coefficient
> > +(default: enabled).
>
> Why is it enabled by default?

Because currently, it's already on, and x264's cli also has it by default.


> > +This will remove some details, so it will save bits that can be spent
> > +again on other frames, hopefully raising overall subjective quality.
> > +If you are compressing non-anime content with a high target bitrate, you
> > +may want to disable this to preserve as much details as possible.
>
> If that's the case, I think it's reasonable to leave it off by default.

Except that, if I understood correctly, it improves quality in most
cases, except when you're encoding are high bitrates live material.

i.e: it's a nice feature to leave on with low to medium bitrates...

Guillaume
--
I am disillusioned enough to know that no man's opinion on any subject
is worth a damn unless backed up with enough genuine information to
make him really know what he's talking about.

-- H. P. Lovecraft (about the flamewars on FFmpeg and MPlayer-dev mailing lists)
http://www.brainyquote.com/quotes/quotes/h/hplovecr278144.html