At 08:35 PM 5/12/2001 -0700, Dmitri wrote:
>Quoting Eric S. Johansson <[EMAIL PROTECTED]>:
>
>It all depends on default settings of the driver. I am not that
>good in audio ioctls yet :-( But you can use 'rec' and 'play' commands
>to experiment, they do change settings as needed, and they have quite
>useful --help option.
>
>But I wouldn't be to worried about internal structure of the audio data.
>All you need is to make it work with your speech recognition software.
>
> > So I try the same test on /dev/audio1 and I get very different numbers
> > looking like 8080 7f80 807f and other things looking like it's just two
> > samples. Am I getting messed up by the built-in driver forcing the USB
> > driver to 8-bit?
>
>It is probably default setting too. USB devices have several "native"
>formats that they are willing to produce or consume, and on top of that
>any software can convert formats too. Do not worry about that - until
>it causes a problem.
>
> > capture audio data; talking real loud:
> >
> > 0022460 7376 7576 7c72 8580 9592 9395 7d8b 6671
>
>Yes, this is 8-bit stream. Value 0x80 is silence (center line) there.
>
> > an unrelated problem seems to be that the built-in audio somehow seems to
> > turn on the built-in microphone and I get this nice little feedback loop
> > between the built-in microphone and the built-in speakers.
>
>Use a mixer app (like gmix) and unclick "Recording" button on the
>built-in card tab.
if I do that, then the entire microphone circuit is dead. If the
microphone is live at all, something is feeding the audio back. (But this
is getting far afield and only matters because I was going to try and use
the built-in audio for a ham radio application.)
> > I'm also having trouble with getting the mixers to
> > work with the USB device.
> > They only want to work with the built-in device.
>
>You have mixer, it has been constructed by the driver. Have a look
>at gmix, it should have two tabs - one for each audio device.
it has tabs for:
first tab: OPL3-SAx and AD1848 (through MS| <-- tab ends
second tab: MS sound system (CS4231)
neither of them relate to the USB audio. Any ideas where it gets the
information for the tabs?
>You need now to try your audio application. Use 'rec' to make sure
>you can capture sound from your USB microphone, and use 'play' to
>play it back on internal sound card. Try several formats just in
>case. I don't see anything being badly broken or out of order.
>It's time to start using your voice recognition software.
it's time only if I can get the audio to work 16-bit. I'll try some
experimentation today and report back.
---eric
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