Hi Tanu, Thanks for replying :-) When upmixing is disabled, mono playback is silent but does not generate errors that I can see from pulseaudio -vvv or any notifications. Here's a bit of output: I: [pulseaudio] source-output.c: Trying to change sample rate I: [pulseaudio] source-output.c: Resampling enabled to 44100 Hz D: [pulseaudio] module-suspend-on-idle.c: Sink alsa_output.pci-0000_01_00.1.hdmi-surround-extra1 becomes busy. D: [pulseaudio] resampler.c: Channel matrix: D: [pulseaudio] resampler.c: I00 I01 I02 I03 I04 I05 D: [pulseaudio] resampler.c: +------------------------------------ D: [pulseaudio] resampler.c: O00 | 0.000 0.000 0.000 0.000 0.000 0.000 I: [pulseaudio] remap.c: Using generic matrix remapping I: [pulseaudio] resampler.c: Using resampler 'peaks' I: [pulseaudio] resampler.c: Using float32le as working format. D: [pulseaudio] memblockq.c: memblockq requested: maxlength=33554432, tlength=0, base=12, prebuf=0, minreq=1 maxrewind=0 D: [pulseaudio] memblockq.c: memblockq sanitized: maxlength=33554436, tlength=33554436, base=12, prebuf=0, minreq=12 maxrewind=0 I: [pulseaudio] source-output.c: Created output 14 "Peak detect" on alsa_output.pci-0000_01_00.1.hdmi-surround-extra1.monitor with sample spec float32le 1ch 25Hz and channel map mono This particular one is from a mono youtube video played in Chrome, the behaviour is the same in other applications too. For the plans comment, this is just a quote referring to fine-grained control over upmixing from this thread: http://lists.freedesktop.org/archives/pulseaudio-bugs/2009-December/003553.html That was several years ago though. I think your option would be good, to make sure I understand it it would be: - no upmixing of stereo sources (or any multichannel source) with the upmix module disabled - mono would still be upmixed (probably to all channels) regardless of the upmix module being active or not Or something functionally equivalent to the above. If I can help with testing I'm happy to try any patch on my system. Cheers Carl On 21 March 2013 07:58, Tanu Kaskinen <tanuk at iki.fi> wrote: > On Wed, 2013-03-20 at 10:34 +0000, Carl Gridley wrote: > > Hi folks, > > > > I have found some old messages on this, but wondered if anything had > > changed or anyone had any bright ideas on it now :-) > > > > I have PA 2.1 running on Kubutu 12.10. > > > > It is connected via HDMI to my AV receiver and so I have 5.1 PCM output. > > > > I've got two music speakers, and the surround speakers are much smaller, > so > > I turn 5.1 upmixing off. I also turn off LFE mixing as the receiver does > a > > good job and can set a crossover per channel. > > > > Everything sounds great, but mono sounds don't work as they can't get > > upmixed to stereo. If I re-enable upmixing, mono works, but then all > stereo > > sources get upmixed which I'd prefer not to. > > I haven't bothered to try this myself: how do mono streams behave when > upmixing is disabled? Does the stream fail to connect to the device, or > does it connect but is silent, or something else? > > > I know from the previous notes there were no plans to allow more control > > over upmixing, has this changed at all? > > No plans in what sense? Patches for enabling sensible use cases will be > accepted, and this use case definitely is sensible. If you mean "no > plans" as in "nobody has promised to do the work", then you're right, > and nothing has changed. > > > An option just to enable mono > > upmixing only would be fantastic :-) > > > > Or even map mono to the centre channel if one is reported. > > I'm not sure there is need to have any new options. If mono streams > don't work at all in case upmixing is disabled, I don't see why anyone > would want to keep the current behavior. We could have a special case > for mono-only streams so that such streams would always be upmixed to > all channels (or some smart selection of a subset of the available > channels, but all channels is easier to implement). > > I looked at the remixing code to determine what it would take to > implement this, and it seems simple enough that I'll write a patch > myself. > > -- > Tanu > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.freedesktop.org/archives/pulseaudio-discuss/attachments/20130321/f927922b/attachment.html>
