Re: [OT] ALSA userspace API complexity

From: Jan Engelhardt
Date: Fri Jan 06 2006 - 02:46:31 EST


>> > If you have sound device without this soft mixing is moved to user space
>> > .. but applications do not need know about this even now because all
>> > neccessary details are handled on library level. Is it ?
>> > So question is: why the hell *ALL* mixing details are not moved to kernel
>> > space to SIMPLE and NOT GROWING abstraction ?
>>
>> Because many people believe that the softmix in the kernel space is
>> evil.
>>
>This is the usual argument against kernel level mixing. Somebody has once
>said that all this is evil. However this is not necessarily correct.
>

I'm going with "is evil". Better let userspace have a segfault than a kernel
oops. I am having quite a moody feeling when running even my own things like
http://alphagate.hopto.org/quad_dsp/

>Kernel mixing is not rocket science. All you need to do is picking a
>sample from the output buffers of each of the applications, sum them
>together (with some volume scaling) and feed the result to the physical
>device. Ok, handling different sample formats/rates makes it much more
>difficult but that could be done in the library level.



Jan Engelhardt
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