[Klug-general] Linux Audio

[James Morris]

On 12 January 2012 17:30, James Morris <jwm.art.net at gmail.com> wrote:
> On 12 January 2012 17:06, Peter Childs <PChilds at bcs.org.uk> wrote:
>>
>>
>> On 12 January 2012 14:40, James Morris <jwm.art.net at gmail.com> wrote:
>>>
>>> On 12 January 2012 12:54, Peter Childs <pchilds at bcs.org> wrote:
>>> > Does anyone have a better clue than me on Audio Under Linux.
>>> >
>>> > I ideally want to be able to record/sample, then stream and analyse the
>>> > sound.
>>> >
>>> > I think GStreamer should be the right weapon but it seams over complex
>>> > if
>>> > you want to do anything more than write a simple client using the
>>> > filters/plugins already available.
>>> >
>>> > There seams to be so many Audio Libraries around, that I just keep
>>> > drawing
>>> > blanks.
>>> >
>>> > If something is better than GStreamer then I'll use that, People excel
>>> > the
>>> > virtues of Jack but I've never got that working......
>>>
>>>
>>> Hi Peter,
>>>
>>> I've mentioned before about doing a talk on Jack, and I'm still
>>> interested in doing that - just it kinda got a little forgotten about.
>>>
>>> Have to say I don't know anything about Gstreamer or Pulse so no
>>> mention by me of them (except to disable Pulse if you're trying to use
>>> Jack).
>>>
>>> > Does anyone know enough to be able to do a talk maybe?
>>>
>>> With Jack I can show you recording and analysis. I don't have
>>> experience with streaming or really know much about it. Can you
>>> explain more about this part of what you want to do? It sounds like a
>>> 3 stage process - record, stream, analyse - rather than an
>>> simultaneous in-line process.
>>>
>>> With Jack you can simultaneously record and analyse. What Jack has
>>> that others don't is flexibility and routing between applications.
>>>
>>> I can also give some basic guidance on setting up a system for use with
>>> Jack.
>>>
>>> It wouldn't be a long talk, nor would it be a jam session, nor would a
>>> 20K rig be required ;-)
>>>
>>
>> If Jack is so great why is it that all the main disros built with
>> GStreaner/Pulse/Alsa stack?
>
> I tried to explain this before the last time Linux Audio was slagged
> off on this list as being a mess. JACK is for pro-audio users. Within
> the IT industry, Pro-audio users are a minority, within Linux, they're
> an even smaller minority.

Additional reasons why Jack is not a default are, (and i'm no expert
at all) jack is designed to meet Real Time scheduling requirements.
All 2.4 and (less recent) 2.6 series Kernels required patching with
Ingo Molnar's (hard?) RT patchset. Linus and others have been
reluctant to include these patches within the mainline Kernel.
Currently the recent 2.6/3.n series kernels include soft real-time
options which are acceptable for many users but some may have stricter
latency requirements (hard rt).

Further, the integrated sound chips within motherboards are poor when
it comes to meeting RT requirements (and this is the same in windows
too) as other many consumer-orientated (rather than pro or pro-sumer)
sound boards, ie most soundblasters.

btw, alsa is a kernel module - jack can use it as a backend


>
>> Thats without the large number of apps that use PortAudio/OSS/NAS ,,,,,
>
> It's called choice.
>
>>
>> Plus the shear lack of good language bindings..... and upto date
>> documentation....
>
> C++ seems to be the language of choice for linux audio applications,
> with a small minority using C.
>
> I'm not trying to evangelize about how great Jack is, I just offered
> to do a talk. If no one's interested I won't bother.
>
> James.
>
>>
>> Peter.
>>
>>>
>>>
>>> Cheers,
>>> James.
>>>
>>> > Peter.
>>> >
>>> > _______________________________________________
>>> > Kent mailing list
>>> > Kent at mailman.lug.org.uk
>>> > https://mailman.lug.org.uk/mailman/listinfo/kent
>>>
>>> _______________________________________________
>>> Kent mailing list
>>> Kent at mailman.lug.org.uk
>>> https://mailman.lug.org.uk/mailman/listinfo/kent
>>
>>
>>
>> _______________________________________________
>> Kent mailing list
>> Kent at mailman.lug.org.uk
>> https://mailman.lug.org.uk/mailman/listinfo/kent