[MPlayer-users] Re: No sound/no audio bt878 with mencoder

[Stefan Seyfried]

Steve <sec at braingia.org> writes:

> I've search google and the archives for assistance and have so far come up 
> empty.  I'm troubleshooting a problem where I get no sound with an 
> mencoder captured file.  When viewing tv through xawtv, I get audio fine 
> but I can't figure out the correct options to give to mencoder to get 
> sound within a captured/recorded file.  The video comes through fine.
> 
> I have an AverMedia TVCapture 98 card with the audio connected directly to 
> the card.  When insmod'ing the module, the card is detected correctly.  I 
> have bttv, tuner, and tvaudio modules loaded.

First: i never could get btaudio to work with my "AverMedia TVPHONE 98",
i have to use the loopback-cable.

> Here's the latest command line that I've tried:
> 
> /usr/local/bin/mencoder -tv 
> on:driver=v4l:device=/dev/video:norm=NTSC:width=640:
> height=480:input=1:forceaudio:forcechan=2 -oac mp3lame \
> -ovc lavc -lameopts vbr=0 -lavcopts vcodec=mpeg4 -vop pp=lb \ 
>  -endpos $1 -o $f.avi

have you ever tried specifying the audiodevice in the "-tv" option? it is
adevice=...
On the other hand, it is very possible, that you just set the wrong channel
to "record" and did not raise igain, since you did not write anything about
it.

I always use "record", which comes with xawtv and has a nice VU-meter in
the Ascii-terminal and "aumix" to switch around the recording channel
(select e.g. "line1" and press Space, you should get a green "R" next to
the line1 slider). Then you probably need to raise the "Igain"-level until
you get a signal on the "record"-VU meter.

Note that you have to do this every time before starting mencoder and that
some desktop environments (KDE for example) will store and restore your
mixer settings on logout/login and that some sound system startscripts
(SuSE's alsasound for example) will store and restore sound settings on
shutdown / reboot. You can setup sound noninteractive with aumix.

 
> Video stream: 1178.862 kbit/s  (147357 bps)  size: 152439 bytes  1.034 
> secs  30 frames
> 
> Audio stream:  127.997 kbit/s  (15999 bps)  size: 16300 bytes  1.019 secs

this probably tells us, that some sound was recorded, but probably it just
is silent. So you have to unmute your mixer.

if you are using btaudio or something like that, you probably need to use
/dev/mixer1 and /dev/dsp1 or something like that.

A last note: having sound when watching tv has not much to do with recording
video and sound with mencoder,

Good luck :-)
-- 
 Stefan Seyfried, seife at gmane0305.slipkontur.de
+----------------------------------------------+

"If you want to travel around the world and be invited to speak at a lot of
 different places, just write a Unix operating system." -- [Linus Torvalds]