ANNOUNCE: Software equalizer for openmoko

[Russell Sears]

Michael 'Mickey' Lauer wrote:
> Am Mittwoch 23 Juli 2008 09:11:20 schrieb Russell Sears:
>> I've modified gst-plugin-equalizer to use fixed-point arithmetic.  This
>> means that it's (barely) fast enough to provide bass, midrange and
>> treble control for ogg files played back via alsa.
>>
>> Here's a link to binaries (compiled for the factory image) and the patch:
>>
>> http://hedora.ath.cx/moko/
> 
> Amazing work. I'll add this to OpenEmbedded, so all platforms will get the 
> benefits.
> 

Please do, but wait a few days; I want to test it with a real music 
player, fix comments, etc.

> Since you already took a look into GStreamer, could you check why ogg is
> taking so many resources? Do we use vorbis/tremor or not? Is there any chance 
> for a speedup?

I'm working on it.  We're using tremor, but there are some things that 
might help it, in the order I'd like to try them:

- LOW_MEM branch, which reduces memory utilization (and perhaps cache 
misses).
- Tremolo, which is a branch of tremor which gives up on portability and 
targets ARM.  It incorporates the LOW_MEM changes.  The author claims a 
15-20% speed improvement.
- _LOW_ACCURACY_ flag, which can flip a few of the least significant 
bits but is faster.

-Rusty