Sören Apel wrote:
Heya,
On Sat, 2008-07-12 at 14:27 -0700, Russell Sears wrote:
I've noticed that my freerunner is *almost* fast enough to play my ogg
vorbis files; running a second app, or even gpsd causes the media player
to skip, then to go silent.
Yep.
What's been done to get ogg vorbis to perform well so far? ogg123,
oggdec seem to be able to decode in roughly 2/3's realtime, which is
similar to the CPU usage of openmoko-mediaplayer.
If I remember correctly it was a problem with the sample rate/sample
format,
meaning that resampling had to take place - which eats CPU like candy.
Ouch. What sample rate does the hardware provide, and does pulseaudio
or gstreamer do the resampling? Also, decoding to /dev/null is slow...
That shouldn't resample should it?
I've noticed that things I've encoded more recently seem to be less
likely to play (perhaps I changed an encoding setting at some point...),
but that it varies from track to track... I'll time some files, and see
if I can find a pattern.
Thanks!
-Rusty
I noticed that gstreamer is using libvorbisi (tremor) since there is no
floating point unit. It looks like there are three ways to make it go
faster:
- Tremolo, which is ARM specific, and claims 15-20% better performance
- _LOW_ACCURACY_ mode
- The "low-mem" branch of tremor
Which of these have been tried so far?
None, as I didn't find the time unfortunately.
You're more than welcome to try these :)
-Soeren
