On Wed, May 12, 2010 at 8:58 AM, Philipp Überbacher <hollunder@xxxxxxxxxxx> wrote:
this is a misleading description. Mobile audio is really quite complex indeed. You have a continual need to be aware of jack-sensing status, and be willing to switch the routing of audio from one output to another at arbitrary times and for arbitrary reasons. You have to consider pausing streams midway to allow for other streams (e.g. a call in the middle of music playback). Depending on the device, you may want to be doing so-called "gapless" playback of music on the device, which implies a moderately complex disk/memory buffering scheme, which only gets more complex if you add crossfading. You may also choose to mix together a steady state stream (eg. music) with alerts (e.g. new message). You may want to switch from high latency during music playback to low latency during a voice call.
Note that all of these issues are much, much close to desktop audio, which is why Nokia, Intel and others seem reasonably happy to use PA for this.
The users that I have seen who are fed up with are generally people who are trying to get JACK and PA to work on the same system with only a single audio interface. The impression that I have (and it may be wrong) is that users who don't try to do this are reasonably happy with PA to the extent that ALSA works correctly for their Intel HDA chipset. They get features that people have wanted for a long, long time (device sharing, per-app sound control, switching output based on jack-sensing status, on-the-fly device switching and more) and most of this stuff works really well. The headaches seem to come mostly from the same place that a lot of JACK user complaints come from these days: poor/incomplete/hard to use HDA driver support.
yes, this was my favorite german _expression_ that i learned while living in berlin. i don't think it applies to PA though. Its happy to be a wollmilchsau and forego the eirerlegende attributes :)
I simply don't think that it can do the mobile thing and the desktop
dance at the same time, since it is still very different.
Mobile can be a lot simpler in many ways. You pretty much only ever need
2 channels, it doesn't need to be flexible, latency doesn't matter at
all, it just needs to be there and not get in the way CPU, memory and
power wise.
this is a misleading description. Mobile audio is really quite complex indeed. You have a continual need to be aware of jack-sensing status, and be willing to switch the routing of audio from one output to another at arbitrary times and for arbitrary reasons. You have to consider pausing streams midway to allow for other streams (e.g. a call in the middle of music playback). Depending on the device, you may want to be doing so-called "gapless" playback of music on the device, which implies a moderately complex disk/memory buffering scheme, which only gets more complex if you add crossfading. You may also choose to mix together a steady state stream (eg. music) with alerts (e.g. new message). You may want to switch from high latency during music playback to low latency during a voice call.
Note that all of these issues are much, much close to desktop audio, which is why Nokia, Intel and others seem reasonably happy to use PA for this.
PA tries to do all of this at once, and at least on the desktop it fails
often enough. Sure, many user complaints are old and the problems might
be solved, but many users are fed up with it already and don't ever want
to try it again.
The users that I have seen who are fed up with are generally people who are trying to get JACK and PA to work on the same system with only a single audio interface. The impression that I have (and it may be wrong) is that users who don't try to do this are reasonably happy with PA to the extent that ALSA works correctly for their Intel HDA chipset. They get features that people have wanted for a long, long time (device sharing, per-app sound control, switching output based on jack-sensing status, on-the-fly device switching and more) and most of this stuff works really well. The headaches seem to come mostly from the same place that a lot of JACK user complaints come from these days: poor/incomplete/hard to use HDA driver support.
There's a fun German _expression_ that fits PA quite well:
"Eierlegende Wollmilchsau"
yes, this was my favorite german _expression_ that i learned while living in berlin. i don't think it applies to PA though. Its happy to be a wollmilchsau and forego the eirerlegende attributes :)
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