[FFmpeg-devel] [PATCH] make fast option with h264 actually do something..

[Måns Rullgård]

Rich Felker <dalias at aerifal.cx> writes:

> On Wed, Feb 20, 2008 at 01:17:00AM +0000, M?ns Rullg?rd wrote:
>> Rich Felker <dalias at aerifal.cx> writes:
>> 
>> > On Tue, Feb 19, 2008 at 09:22:31PM +0100, Michael Niedermayer wrote:
>> >> On Tue, Feb 19, 2008 at 09:10:38PM +0100, Michael Niedermayer wrote:
>> >> > On Tue, Feb 19, 2008 at 01:26:24AM -0500, Rich Felker wrote:
>> >> > > Currently, the FAST flag for h264 only affects motion functions for
>> >> > > non-ref frames, making it mostly useless. This patch makes it affect
>> >> > > all motion compensation. Benchmarks on my K6, using mplayer
>> >> > > -benchmark:
>> >> > > 
>> >> > > Without fast: 17.6 sec
>> >> > > With current fast: 17.2 sec
>> >> > > With patch applied: 16.6 sec
>> >> > > 
>> >> > > I did not notice any visible corruption, but even if there is some,
>> >> > > that's the idea of the 'fast' flag...
>> >> > > 
>> >> > > Comments welcome.
>> >> > 
>> >> > patch ok
>> >> 
>> >> after some more carefull tests, i retract that approval, patch rejected,
>> >> it breaks decoding of BA1_FT_C.264 with very vissible artifacts.
>> >
>> > Would it be possible to make the level configurable or to at least
>> > apply the fast-mode to all B-frames instead of only non-reference
>> > ones? Error should not have time to sufficiently accumulate during
>> > B-frame sequences, only over long intervals between I-frames.
>> 
>> Rich, why can't you just accept that your K6 is too slow?
>
> There's no fundamental reason why it should not be able to play
> normal-resolution h264 video.

Eh?

> But in the meantime until things are sufficiently optimized, it
> would be nice if the 'fast' option really did what it's supposed to
> do. :)

It is supposed to be useful.  If artifacts are too bad, it is no
longer useful.

> Even nicer would be support for lowres mode -- this would be
> useful not just to folks like me but to people with fast computers
> who want to play HD content.

If I'm playing HD content, I want to see the full resolution.  If I
didn't, I wouldn't bother getting the HD version in the first place.

-- 
M?ns Rullg?rd
mans at mansr.com