Wed Mar 28 10:40:43 CEST 2012
other sound APIs to ease the pain of cross-platform development of audio
applications, right? What's wrong with letting ALSA convert the samples
for you then?
> b) Subdevices are not enumerated by Portaudio at present, and so only 2 of the
> 4 channels can be accessed. If the unit had presented a single 4-channel
> device all the channels would have been available.
Ok, I see your problem, but certainly, PortAudio is the place to get
this fixed, not the driver.
>> The device itself implements 4 audio channels which are synced to each
>> other. In other words: the hardware is not able to only enable one of
>> them and leave the other ones paused or set sample rates individually.
>> When I implemented the driver, it seem most logical to follow the way
>> the device denotes it channels though. The documentation and silk screen
>> presents them as pairs of stereo, and so the driver does the same thing.
> I am just interested whether you think it would be possible for the driver to
> be modified to support a single 4-ch device, perhaps through a module option?
Technically, it would certainly. But the problem is that there are quite
a number of applications out there using these devices and making their
assumptions about the implementation as it stands. So we won't accept a
patch that changes the behaviour of these cards for all users.
So clearly, the issues you're seeing are due to missing features in
PortAudio, and it should be fairly easy to add them there.
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