Re: [Gap-dev-discuss] Cynthiune - ALSA backend

[Philippe Roussel]

Le 30/05/2012 09:42, Riccardo Mottola a écrit :
>> Looking at alsa documentation it's obvious the alsa backend is overly
>> simplistic, even if it works in most cases. The API provides functions
>> to determine what the harware is capable of for example, we could
>> probably use those to handle rare configurations. I will to propose
>> patches in the future, when I'll have more time.
>>
> Yes, I had that impression too, I looked at the alsa documentation to
> understand some parameters. I also checked around mailing lists.
> Apparently the ability to accept different sample rates is
> hardware-dependent. I got the impression though that "soft resample"
> should fix that. I am a bit confused. How can the backend know it needs
> to resample if I open it with a different rate (that is what most code I
> found around does and that is what I tried in the fall-back call I
> implemented).

Yes, that's what I wondered when I read your patch... There are
functions to set hardware and software parameters, they probably are
part of the answer.

> We need to take 8bit vs 16bit in account, I'm pretty sure about that,
> this will affect potentially many backends, like the endianness change did.
> 
> Anyway, perhaps big changes need to be done after a release.. what we
> have is still much better than before.

Agreed.

> On the same machine, the OSS backend works fine though. Since it is not
> real OSS, but alsa-oss emulation...
> The AO backend instead has endianness problems, MP3s play like garbage.
> MP3s need "native endianness".

What backend are you using for AO ?

Feel free to change the AO backend so that it works on your various
system if you have time, I'll make sure it still work for me !

But for now I would say that, unless we can find bugs that crash the
application, the code shouldn't change much before a release.

Thanks,
Philippe


Thanks,
Philippe