Re: [gentoo-user] No Sound while video capturing with guvcview

[meino.cramer@gmx.de]

Kfir Lavi <lavi.kfir@gmail.com> [11-05-08 13:28]:
> On Sun, May 8, 2011 at 12:35 PM, <meino.cramer@gmx.de> wrote:
> 
> > Kfir Lavi <lavi.kfir@gmail.com> [11-05-08 11:32]:
> > > On Sun, May 8, 2011 at 12:00 PM, <meino.cramer@gmx.de> wrote:
> > >
> > > > Hi,
> > > >
> > > > may be one can help me...
> > > >
> > > > I am using a webcam (lsusb: Bus 001 Device 002: ID 1415:2000 Nam Tai
> > > > E&E Products Ltd. or OmniVision Technologies, Inc. Sony Playstation
> > > > Eye) on my window board to capture videos from the crow, which often
> > > > visits me  in summer.
> > > >
> > > > The PS-Eye cam has one (four?) microphones to capture audio and
> > > > delivers up to 60 fps.
> > > >
> > > > The setup was working last summer with video AND audio.
> > > >
> > > > This summer only video is captured. The resulting video file
> > > > seems to contain a "null audio" (no sound samples other than
> > > > zeroes...)
> > > >
> > > > When playing the file with mplayer, this is the output on the terminal
> > > > (the video plays ok beside the fact that there is no sound to hear...)
> > > >
> > > >    [aviheader] Video stream found, -vid 0
> > > >    [aviheader] Audio stream found, -aid 1
> > > >
> > > >    Badly interleaved AVI file detected - switching to -ni mode...
> > > >    AVI: No audio stream found -> no sound.
> > > >    VIDEO:  [MJPG]  640x480  24bpp  60.094 fps  29695.7 kbps (3625.0
> > > > kbyte/s)
> > > >    Clip info:
> > > >    Title:
> > > >    Software: guvcview-1.4.5
> > > >    Comments:      Sun May  8 09:51:35 2011
> > > >
> > > >
> >  ==========================================================================
> > > >    Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
> > > >    Selected video codec: [ffmjpeg] vfm: ffmpeg (FFmpeg MJPEG)
> > > >
> > > >
> >  ==========================================================================
> > > >
> > > >
> >  ==========================================================================
> > > >    Opening audio decoder: [pcm] Uncompressed PCM audio decoder
> > > >    AUDIO: 44100 Hz, 1 ch, s16le, 705.6 kbit/100.00% (ratio:
> > 88200->88200)
> > > >    Selected audio codec: [pcm] afm: pcm (Uncompressed PCM)
> > > >
> > > >
> >  ==========================================================================
> > > >    AO: [alsa] 48000Hz 1ch s16le (2 bytes per sample)
> > > >    Starting playback...
> > > >    Movie-Aspect is undefined - no prescaling applied.
> > > >    VO: [gl2] 640x480 => 640x480 Planar 422P
> > > >    [gl2] You have OpenGL >= 1.2 capable drivers, GOOD (16bpp and BGR is
> > > > ok!)
> > > >    [gl2] antialiasing off
> > > >    [gl2] bilinear linear
> > > >    A:  -0.0 V:   1.3 A-V: -1.265 ct: -0.126  77/ 77 14% 88%  0.0% 0 0
> > > >    Capturing not enabled (forgot -capture parameter?)
> > > >    A:  -0.0 V:  14.8 A-V:-14.844 ct: -1.486 893/893 10% 89%  0.0% 0 0
> > > >
> > > > What can I do/check/test/experiment to get back the audio again....?
> > > >
> > > > Thank you very much for any help in advance!
> > > >
> > > > Have a nice sunday!
> > > > Best regards
> > > > mcc
> > > >
> > > >
> > > > From your output it shows that the sound is not null.
> > > Does your sound works playing other files (alsamixer)?
> > > Can you record now a picture with the webcam and play it with sound
> > after?
> > >
> > > Kfir
> >
> > Hi Kfir,
> >
> > thank you for your reply! :)
> >
> > sorry, English isn't my mothers tongue...
> >
> > When playing other videos there is no problem with the sound.
> >
> > What did you mean with
> >
> >    "Can you record now a picture with the webcam and play it with sound
> > after?"
> >
> >
> > mcc
> >
> >
> > You said that this file is a recording of the webcam with sound.
> Can you record again from your webcam and then play the file?
> Does the file you record is the same compression algorithm as the file that
> doesn't work?
> 
> Kfir

The settings (compression algo, audio samplerate and device and such)
are stored in a config file which I didnt't touch.
Currently, when I record  from the webcam I get the effects described
above: Video yes, audio no with mplayer output as given above...

May /I have to change the settings/ for what reason ever?!?

mcc