Bug 15913 – Investigate ARM-optimized Tremor patch

Bug 15913 - Investigate ARM-optimized Tremor patch

Summary:

Investigate ARM-optimized Tremor patch

Status:	NEW

Product:	SqueezePlay
Classification:	Unclassified
Component:	Audio
Version:	7.5.x
Platform:	PC Other

Importance:	P2 enhancement (vote)
Target Milestone:	Future
Assigned To:	Andy Grundman

URL:
Keywords:	codec

Depends on:
Blocks:
	Show dependency tree / graph

Reported:	2010-03-18 10:45 UTC by Andy Grundman
Modified:	2011-02-11 15:41 UTC (History)
CC List:	2 users (show)

See Also:
Category:	---

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Description Andy Grundman 2010-03-18 10:45:42 UTC

The Rockbox team has a patch to add some ARM assembler code to Tremor's MDCT functions.

Mailing list thread: http://lists.xiph.org/pipermail/tremor/2010-March/001607.html

Current patch: http://duke.edu/~mgg6/rockbox/tremor_ffmpeg_imdctv6.patch

Also, possibly some of this could be ported to other codecs that have performance problems.

Comment 1 Dave Hooper 2011-02-11 15:41:42 UTC

For your information, I helped with a number of parts of the aformentioned rockbox development, and we have proposed bringing a number of those changes to the Tremor main line at xiph.org .   We saw >10% reduction in CPU usage on ARM7TDMI from the improved MDCT code.  In addition, rockbox Tremor has a number of significant other optimisations (including some simple special-casing to improve performance on the most common cases) which are also not present in Tremor mainline.   These features are all today available in the main rockbox svn repository  (the patch below is now out of date)