[Pkg-alsa-devel] Bug#541786: Bug#503839: /usr/lib/alsa-lib/libasound_module_pcm_vdownmix.so: vdownmix from 5.1 does not incorporate LFE channel

[Apelete Seketeli]

On Mon, Sep 7, 2009 at 21:13, Josh Triplett<josh at joshtriplett.org> wrote:
> "not working" seems to be expected; a segfault seems like a bug
> regardless. :)

What I was trying to say is that you can expect the bug: if you define
a pcm device named "surround51" as a vdownmix type, and then 'plug' it
as a slave pcm in another vdownmix type pcm device...well, here comes
the bug. :)

> With your setup, does "speaker-test -c 6 -t wav" generate sound for all
> six channels?

Ok, so I don't get the .1 output either, but is it relevant here ? The
speaker test doesn't output it, but any 5.1 video just plays fine, 6
channels and all. At lest I assume, since I don't feel like there's
any sound missing while watching...

> It certainly *shouldn't* depend on the sound card.  Mixing 5.1 to 2.0 in
> software should work anywhere, and I have working 2.0.  Of course, that
> doesn't mean it *doesn't* depend on the sound card, just that it
> *shouldn't*. :)

Well, here is what I get on an X60:


~$ speaker-test -c 6 -t wav

speaker-test 1.0.20

Playback device is default
Stream parameters are 48000Hz, S16_LE, 6 channels
WAV file(s)
Rate set to 48000Hz (requested 48000Hz)
Buffer size range from 64 to 16384
Period size range from 32 to 8192
Using max buffer size 16384
Periods = 4
was set period_size = 4096
was set buffer_size = 16384
 0 - Front Left
 4 - Center
 1 - Front Right
 3 - Rear Right
 2 - Rear Left
 5 - LFE
Time per period = 8,401077


I'll be glad to further test too, since there's obviously something
strange here.

Cheers.
--
Apelete Seketeli <apelete at seketeli.org>