ffmpeg doesn't record sound from WinTV.

[Nicolas Blais]

On December 30, 2005 06:43 am, Jacob Meuser wrote:
> On Fri, Dec 30, 2005 at 10:57:29AM +0000, Steve O'Hara-Smith wrote:
> > On Thu, 29 Dec 2005 20:24:04 -0800
> >
> > Jacob Meuser <jakemsr at jakemsr.com> wrote:
> > > On Thu, Dec 29, 2005 at 01:39:21PM +0100, Frank J. Beckmann wrote:
> > > > Moin,
> > > >
> > > > ffmpeg records sound from outher devices. So I guess that it doesn't
> > > > tell the
> > >
> > >                                            
> > > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > >
> > > > TV card to send the audio stream to it's line out. ffmpeg has the
> > > > only really
> > >
> > >   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
> > >
> > > no, bktr(4) always does that.  it is only possible to select the
> > > inputs. all outputs are enabled when the tuner is unmuted (which
> > > happens by default when the tuner is open()'d).
> >
> > 	Yes that should be the case - but ffmpeg will emit an error message
> > if opening the tuner fails and that error message is not present.
> >
> > > do you hear audio when you run the above ffmpeg command?  if so, then
> > > the problem is solely with the audio grabbing, not bktr.  make sure
> > > your mixer is set right.
> >
> > 	The mixer settings originally posted look correct to me (assuming
> > the plug really is in line and not line1 or something silly like that).
>
> yup, missed that.
>
> only other things I can think of, are a) make sure the soundcard supports
> recording of 48kHz 16-bit stereo (again, would probably see an error
> message if not) and b) check that ac3 encoding actually works in that
> version of ffmpeg (and that whatever is playing it back supports ac3
> decoding).  otherwise, maybe try changing audio parameters.
>
> still, though, if you hear sound when you run the ffmpeg command, the
> problem is not in bktr, but audio.  bktr just sends audio to the
> soundcard.  you don't record audio from bktr, but from the soundcard.

Does it record the video?  If I do this:
ffmpeg -target ntsc-dvd -vd /dev/bktr -ad /dev/dsp -ac 2 fft.mpeg

I get a dvd-size blue screen with no sound.

But If I do this:
transcode -i /dev/bktr0 -x bktr=norm=ntsc:vsource=tuner:asource=tuner,oss -g 
640x480 -y ffmpeg -F mpeg4 -p /dev/dsp -o out  

It works.  Nice audio, nice video.

Mixer:
Mixer vol      is currently set to  75:75
Mixer pcm      is currently set to  75:75
Mixer speaker  is currently set to  75:75
Mixer line     is currently set to  75:75
Mixer mic      is currently set to   0:0
Mixer cd       is currently set to  75:75
Mixer rec      is currently set to   75:75
Mixer igain    is currently set to   0:0
Mixer ogain    is currently set to  50:50
Mixer line1    is currently set to  75:75
Mixer phin     is currently set to   0:0
Mixer phout    is currently set to   0:0
Recording source: line

(Notice that rec = 75:75) Without that, even selecting the right input no 
audio will be recorded.

Nicolas.
-- 
FreeBSD 7.0-CURRENT #7: Mon Dec 26 12:43:20 EST 2005     
root at clk01a:/usr/obj/usr/src/sys/CLK01A 
PGP? (updated 16 Nov 05) : http://www.clkroot.net/security/nb_root.asc
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-multimedia/attachments/20051230/d7dcd8b8/attachment.bin