Mailing List Archive: Playback optimization..

I just committed a patch by (mostly) Matt Zimmerman that really improves the
speed of video playback when using mpeg4. rtjpeg is also improved a little,
but not nearly as much.. Basically, it removes extra full-framesize copies
from the playback pipeline. So, this drops the CPU used in live-tv mode down
under 70% on my XP 1800+ with mpeg4 @ 3300 bps, 640x480, and it bottoms out
below 60% at times, depending on the scene. The rtjpeg codec is helped as
well, but not quite to the same degree.

Anyway, I think I've gotten all the bugs worked out of this, so if people can
please confirm that things still work for them, that'd be great. If there's
any cases of video corruption, or crashes, or whatnot, please let me know.

Isaac

Damn... Playback of both 640x480 and 480x480 files recorded
at 3300 bitrate never goes above 2.5% on my Athlon XP 2000+.
Not sure exactly what it was before but I know it was more.
Now a lot of the time top actually uses more cpu.

Another issue... I have some problems recording 2 shows at
the same time (480x480 @ 3300). One show gets recorded just
fine while the other seems to be recorded in slow-motion.
I'm suspecting that I may have io problems writing to the
drive since I still have ~10% cpu idle. Is there any way of
monitoring throughput on the IDE bus?

-Emil

On Wed, 20 Nov 2002 17:24:39 -0800 (PST), Isaac Richards
wrote:

>
> I just committed a patch by (mostly) Matt Zimmerman that
> really improves the
> speed of video playback when using mpeg4. rtjpeg is also
> improved a little,
> but not nearly as much.. Basically, it removes extra
> full-framesize copies
> from the playback pipeline. So, this drops the CPU used in
> live-tv mode down
> under 70% on my XP 1800+ with mpeg4 @ 3300 bps, 640x480,
and
> it bottoms out
> below 60% at times, depending on the scene. The rtjpeg
> codec is helped as
> well, but not quite to the same degree.
>
> Anyway, I think I've gotten all the bugs worked out of
this,
> so if people can
> please confirm that things still work for them, that'd be
> great. If there's
> any cases of video corruption, or crashes, or whatnot,
> please let me know.
>
> Isaac
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