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Re: [pulseaudio-discuss] Preferred resampler method on armhf.


20.11.2014 15:58, David Henningsson wrote:

On 2014-11-20 08:40, Alexander E. Patrakov wrote:
20.11.2014 12:35, David Henningsson wrote:
Crossposting to Debian and upstream lists.

Apparently Debian has a patch that uses fixed point by default on armhf,
so I'm just echoing Luke's question here: Has anybody performed any
testing or benchmarks across armhf hardware, w r t fixed point vs
floating point resampling with speex and PulseAudio?

That patch has been superseded by this commit:


So, if you prefer a fixed-point resampler on armhf (or, for that matter,
on any other architecture), just compile speex with --enable-fixed-point

Well, this is a more of an "upstream default" question rather than a
"why don't you recompile speex" question, and one where it might make
sense to come up with something reasonable across the board; either by
upstreaming "fixed point by default for armhf", or by Debian to drop its

It does not look likely to me that PulseAudio upstream and Debian would
correspond to so different machine/user scenarios so that a Debian
specific patch would make sense here.

Indeed, a Debian-specific patch does not make sense.

But, even before my patch, and assuming that someone wrote a different solution to the bug that led to it, why would they want to default to speex-float-X on a fixed-point speex, or to speex-fixed-X on a floating-point speex library? Look, the first thing this resampler does is to convert the samples into its preferred representation, possibly undoing the conversion done by PulseAudio.

Ideally, the distinction between speex-float-X and speex-fixed-X resamplers should be completely killed in PulseAudio, exactly because PulseAudio converts between these forms faster than speex does internally.

Alexander E. Patrakov