[pulseaudio-discuss] Switching resamplers

[David Henningsson]

On 09/28/2011 11:20 AM, Arun Raghavan wrote:
> Hey folks,
> We've seen discussions a number of times on IRC about this, and now that
> 1.0's out the door, this might be a good time to consider this.
>
> The current default resampler is speex-float-3, which is on lower-end on
> highly loaded systems can be problematic (cause an underrun flood,
> f.ex.). The current choice among distributions seems to be between
> speex-float-0 (~2.5-3x faster) and speex-float-1 (~2-2.5x faster). On
> embedded systems people might plug in something lighter still (like the
> ffmpeg resampler).
>
> Qualitatively speaking, I can't really perceive the difference between
> speex-float-1 and speex-float-3. Might be a good idea to perform some
> blind trials, though.
>
> So any objections to moving to speex-float-1 as the default?

Without specifying exactly why (because I didn't do it myself), here's 
what Ubuntu does. I think having fixed for ARM would make sense, 
especially if float support is in software.

# Dynamically patch default configuration file
ifeq ($(DEB_HOST_ARCH),armel)
RESAMPLE_METHOD := speex-fixed-1
DEFAULT_FRAGMENTS := 2
DEFAULT_FRAGMENT_SIZE_MSEC := 10
else
RESAMPLE_METHOD := speex-float-1
DEFAULT_FRAGMENTS := 8
DEFAULT_FRAGMENT_SIZE_MSEC := 10
endif

-- 
David Henningsson, Canonical Ltd.
http://launchpad.net/~diwic