[MPlayer-dev-eng] [PATCH]Add support for CoreAVC h264 codec

[Corey Hickey]

Alan Nisota wrote:
> audio was fixed at 48kb/s CBR MP3 (though this really shouldn't matter)

Next time you can just use -nosound for the encoding. No need to do it
now, though, since you used -nosound for playback.

> Each stream was benchmarked 3 times with the average result used
> (reproducibilty was very good)
> encoding was done using:
> mencoder -ovc x264 -oac mp3lame -vf scale=320x180 -srate 8000
> -lameopts cbr:br=48 -x264encopts xxxx
> 
> decoding was done using:
> mplayer -vc coreavc/ffh264 -vo null -nosound -benchmark
> 
> frame comparison was done using:
> mplayer -vc coreavc/ffh264 -vo md5sum -nosound

You can add -benchmark here to speed things up.

> every frame was different.  I guess the next step would be to do a
> frame diff but let's do this one step at a time.  The one thing I can
> say is that the output from CoreAVC looks very good.

Just to make sure I'm understanding you, are you saying that the
decoding of CoreAVC is not identical to that of libavcodec?

Did you do something like this?

$ mplayer -vc coreavc -vo md5sum:outfile=coreavc.md5 ...
$ mplayer -vc ffh264  -vo md5sum:outfile=ffh264.md5  ...
$ diff coreavc.md5 ffh264.md5

...and see that every single line is different?

Michael, was I correct in recommending -vo md5sum for this? Is there any
danger of, say, different color spaces messing up the results?

> I believe I've covered most of what you asked for, but I don't know
> what you mean by:
>>>> * CABAC / CAVLC

-ovc x264 -x264encopts cabac  (this is default)
-ovc x264 -x264encopts nocabac

>>>> * loop filter / disabled loop filter

-ovc x264 -x264encopts deblock (this is default)
-ovc x264 -x264encopts nodeblock

> These runs were done on a Pentium 4 2.8GHz (Northwood) with
> hyper-threading disabled, and a 512K cache.
> 
> If you'd like additional benchmarks, I'll be ahppy to run them, but it
> would be helpful if you could be explicit about what you are asking
> for.

Thanks.

-Corey