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Subject: Reminder: Our codecs are slow on ARM

Reminder: Our codecs are slow on ARM

From: Mike Giacomelli <>
Date: Sun, 1 Jun 2008 12:07:48 -0400

Heres something Andree Buschmann and I have been complaining about for
a while. Taken from the E200 using 192k files:

MP3: 203.96%
AAC: 171.73%
Vorbis: 239.12%
MPC: >>331.76%
WMA: ~230%

Codecs probably need about 250% to run unboosted, and each 3MHz
decrease in average clockspeed saves 1 ma of current from the battery
(PP5024), so only MPC makes optimal use of battery life on PP targets.
 WMA and Vorbis are probably good enough for most purposes, but the
poor performance of AAC and MP3 is disappointing given how popular the
formats are and how mucher slow they are.

Also, this is not just important to PP targets. Nearly all potential
new targets are ARM, and many are mid range ARM9 cores which would
almost certainly benefit from faster codecs too (Creative Zen, M:robe,
Cowan D2, AMS, etc). Not to mention improved MP3 performance benefits
Mpegplayer and probably saves power when used with lots of DSP even on
the fastest targets.

I plan to keep working on WMA and perhaps AAC when I can get away from
my SOC project, but if someone else could pitch in to improve their
preferred format, I'd love to talk to them about it!

Received on 2008-06-01

Page was last modified "Sat May 23 08:12:40 2020" The Rockbox Crew