It seem to me that name hint is not suitable for displaying recording devices
It's other rare for an user to recording from the same source by more than one applications.
You can get low latency by using hw device since PA use maximum buffer in order to save power comsumption for those notebook / netbook.
If your application require high quality (bypass any SRC) , you may need to capture using hardware rate and format instead of using plughw
For the surround51 in the movie , the LFE is generated in the studio instead of recording in real life
In the past , AC97 codec has only one ADC , you can select one capture source only. so most of the sound card using AC97 codec can capture stereo only
The other high end sound card (e.g. ice1712) can only capture in 12 channels
For HDA , it support multiple streamming. some HDA codecs (e.g. alc88x and ad198x) have 3 ADC ( which you can capture three stereo streams concurrently from internal mic, external mic and line in )
The main problem of the recording audio application is unable to select the correct mixer control of the three capture sources
2009/9/11 David Henningsson launchpad.web@epost.diwic.se
Hello,
First; I'm not completely sure how much of this is your issue, and how much is my distribution's fault (Ubuntu). If you believe my problems is due to bugs in the distribution, please say so.
I'm working with a small recording application and I want to enumerate possible recording sources/devices, just to put in a combobox. In my computer I have two soundcards, one on the motherboard and one PCI soundcard (ESI Juli@). I also have Pulseaudio installed, so the devices I want to show up are those three - and possibly alternatives under these, such as analog/digital inputs.
According to Lennart's guide to sound API's, snd_device_name_hint is the way to go, as both snd_card_xxx and snd_config_xxx are deprecated. (Speak up if you don't agree.)
So assuming I do about the same as "arecord -L" does, I get the following output (descriptions omitted) :
front:CARD=Juli,DEV=0 surround40:CARD=Juli,DEV=0 surround41:CARD=Juli,DEV=0 surround50:CARD=Juli,DEV=0 surround51:CARD=Juli,DEV=0 surround71:CARD=Juli,DEV=0 iec958:CARD=Juli,DEV=0 null front:CARD=CK804,DEV=0 surround40:CARD=CK804,DEV=0 surround41:CARD=CK804,DEV=0 surround50:CARD=CK804,DEV=0 surround51:CARD=CK804,DEV=0 surround71:CARD=CK804,DEV=0
I have two problems with this: first thing is that the "pulse" device is not listed. I think that could be solved either by setting "defaults.namehint.showall" to on, or by setting the name hint of the pulse device to be included in the "basic" devices. Would you recommend doing either one of those, and if so, which one?
Second problem is that I don't have surround input on either of my soundcards, so most of the device options above do not make any sense. Even if I try, I have a hard time recording from them (arecord fails to record it with various errors, such as "Sample format non available"). If I instead use "plughw:CARD=name", recording works.
To sum it up, the output I would like to have, is at least these three:
plughw:CARD=Juli plughw:CARD=CK804 pulse
How do I/we get there?
// David
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