[MPlayer-dev-eng] [RFC] change lacv's MPEG-4 encoding options defaults

[Rich Felker]

On Thu, Dec 29, 2005 at 06:24:27PM +0100, Dominik 'Rathann' Mierzejewski wrote:
> On Wednesday, 28 December 2005 at 21:27, Diego Biurrun wrote:
> > On Wed, Dec 28, 2005 at 12:03:26PM -0500, Rich Felker wrote:
> > > On Wed, Dec 28, 2005 at 02:48:45PM +0100, Guillaume Poirier wrote:
> > > > Maybe with latest Michael's commits, further tests should be done to
> > > > find the new best speed/quality tradeoff, but until then, what do you
> > > > guys think?
> > > 
> > > This topic has come up in the past and I've flamed in the past.
> > > Defaults should always be all-off. If users are too lame to RTFM they
> > > should not hope to get a good encode.
> > 
> > Nonsense.  Defaults should be sane.  Programs without good defaults are
> > a major PITA.  Having to handtune everything is OK for a developer and
> > encoding specialist like you, but it is a major inconvenience for the
> > rest of the world.
> > 
> > Also the tradeoff is very bad.  Experienced users will not have problems
> > tweaking the defaults if they don't like them.  Newcomers on the other
> > hand will turn to another tool.
> > 
> > Out-of-the-box behavior is important.  I regularly throw fits when
> > confronted with software that does not have sane defaults.  Just because
> > finding the best defaults is difficult and involves difficult decisions
> > and tradeoffs does not mean it is not a worthwhile goal.
> 
> Agreed. For example, I use at least mbd=2:mv0:v4mv:trell:cbp for every
> encoding job and these seem to be "always win"-type options. Rich said
> v4mv is not good for snow, but couldn't these defaults be used on
> per-codec basis? I mean different for mpeg4, different for snow, etc.?

Not that it's bad, just that it's very questionable whether you want
it. Also it's stupid option overloading. v4mv does not mean "4 motion
vectors per macroblock" in snow. IMO this is a bug.

> I'm definitely in favour of changing the defaults to be more
> quality-focused and adding no-options if someone wants to turn them off.

I'm in favor of instead having a simple profile-like option that
enables many 'always win' options all at once, and still leaving them
off in the default. There's always the possibility that they're not
good (or maybe not even supported, and thus fatal error!) for strange
codecs.

Rich