[MPlayer-users] Playing from v4l NOVIRUS

Wieslaw Kierbedz sprawki at wp.pl
Sat Nov 8 02:20:58 CET 2003


Użytkownik Todd Lyons napisał:
> [Automatic answer: RTFM (read DOCS, FAQ), also read DOCS/bugreports.html]
> 
>>>>I'm trying to play and later archive video/sound 
>>>
>>>>from a v4l device.  The driver (bttv and btaudio) are both 
>>>
>>>>successfully loaded, see below for dmesg output.  Video displays 
>>>>properly with no problems.  But no sound is played. Am I mistaken in 
>>>>thinking that I can have mplayer grab video/audio (physical devices 
>>>>video0 and dsp1) from the capture card and play the video 
>>>>back on the screen with audio out through /dev/dsp (my 
>>>>regular sound chip)?
>>
>>I think mplayer only initialize (unmute) audio-out of tv 
>>card. You can 
> 
> 
> Good, you understand my question exactly.
> 
> 
>>watch tv with sound when the audio-out of tv card and 
>>audio-in (line-in, 
>>aux, cd-in) of sound card are connected. Mplayer is not able to route 
>>audio (am I wrong?). When you choose adevice=/dev/dsp2 you 
>>choose it as 
>>audio-out.
> 
> 
> So I guess what I'm asking for is to be able to specify both the audio input
> device and the audio output device, even though they are on different cards.
> I have to ask the obvious question:  What's the use of saying "use a v4l
> device" if I directly specify the audio devices?  That makes it seem like my
> request is useless.
> 
> I want to somehow say:
>   audio_input=v4l audio_output=alsa
You can only connect it phisically (for mplayer but for xawtv and others 
too).
> Hopefully I'll figure out a way to do this by massaging the commandline.
Mplayer does not use audio-input at all.
> It may also be that I simply cannot do this with mplayer (as you suggest it
> cannot route output to a different chipset than the input is being grabbed
> from).  I may have to encode and then play back the file as two separate
> processes.
You can encode it with mencoder and play as one process :).
For mencoder you can specify only audio-in - opposite to mplayer.
But I am affraid - that should be also default recording source in 
system - anyway
you have to  configure bt as second sound card. Are not you?
>>To use btaudio module you should conneect some amplifier directly to 
>>your Osprey - then you should have to configure it such as second sound 
>>card (I never tried it then I do not know how) - check your sound mixer 
>>for second panel?
>>
>>>>btaudio: registered device dsp1 [digital]
>>>>btaudio: registered device dsp2 [analog]
> 
> 
> I've only been using aumix because in my experience, kmix hasn't worked well
> for me.  I think it's normal that aumix only sees one sound card, though it
> does have a "Video" input slider and it is stereo since I have a balance
> control too.  I'll try aumix without loading the bttv and btaudio modules to
> see if that "Video" control is present.  I will also try kmix again and see
> if it sees a second card.
I prefer aumix too, video in sound card is some more kind of input I 
think (I don't know exactly what) - some like cd-in - if you have SB or 
audigy card
- try oss drivers from http://sourceforge.net/projects/emu10k1 - there 
are tools for routing devices.
> 
> _______________________________________________
> RTFM!!!  http://www.MPlayerHQ.hu/DOCS
> Search:  http://www.MPlayerHQ.hu/cgi-bin/htsearch
> http://mplayerhq.hu/mailman/listinfo/mplayer-users
> 
> 


-- 
Wiesław Kierbedź
gg  2128870; wieslaw_kierbedz at jabber.org
www.v4l.prv.pl (video4linux - podstawy)




More information about the MPlayer-users mailing list