Unable to capture audio from a tv tuner

[Edhoari Setiyoso]

I think I know why I cannot get audio at all from my capture card using
Gstreamer. The card audio input will be activated when I access the video
device. But gst-launch initialize the device with audio volume=0 aka mute.
I tested this behaviour using mplayer by varying the volume variable. The
effect is exactly the same as when I start mplayer with volume=0.

Unfortunately I cannot find any method to set the volume with gstreamer.

Is there anyone can give me a clue on how to set the volume with v4l2src?

Best Regards


On Sun, Mar 3, 2013 at 1:27 AM, Edhoari Setiyoso <edhoari.s at gmail.com>wrote:

> Hi Charlie,
>
> I already confirmed that the audio device is that of tv tuner. The funny
> thing is the audio device active only when I access the corresponding video
> device. I can see from the audio mixer the audio level is moving. As soon
> as I turn off the app accessing the video device, the audio level went down
> completely.
>
> Testing with mplayer showed that I must use "immediate=0" option,
> otherwise I only get video. From the manual it says "A value of 0 means
> capture and buffer audio and video together".
>
> Could you give me a hint on this?
>
> Regards
>
>
> On Sat, Mar 2, 2013 at 2:40 AM, Charlie X. Liu <charlie at sensoray.com>wrote:
>
>> You need to use "arecord -l" to find out and confirm that the "hw:2,0" is
>> your "Avermedia Volar Go M"
>> (
>> http://www.avermedia.com/avertv/Product/ProductDetail.aspx?Id=529&tab=APDri
>> ver) audio device link.
>>
>> Then, simply use "arecord -D hw:2,0 | aplay" or "gst-launch-0.10 alsasrc
>> device=hw:1,0 ! audio/x-raw-int,rate=\
>> 32000,channels=2,depth=16 ! audioconvert ! autoaudiosink" to confirm that
>> you can pre-listening from your device and the hardware works.
>>
>> Next, apply your application ...
>>
>> Good luck and BR,
>>
>> Charlie X. Liu @ Sensoray Company Inc. (http://www.sensoray.com/)
>>
>>
>> -----Original Message-----
>> From: gstreamer-devel-bounces+charlie=sensoray.com at lists.freedesktop.org
>> [mailto:gstreamer-devel-bounces+charlie=
>> sensoray.com at lists.freedesktop.org]
>> On Behalf Of edhoari
>> Sent: Friday, March 01, 2013 9:43 AM
>> To: gstreamer-devel at lists.freedesktop.org
>> Subject: Unable to capture audio from a tv tuner
>>
>> Hi all,
>>
>> I'm fairly new with Gstreamer and trying to build a application to
>> digitize
>> analog video. I'm using Avermedia Volar Go M as capture device for
>> composite
>> input.
>>
>> My problem is that I cannot get any audio from it. I can capture video
>> without problem with the following command
>>
>> gst-launch-0.10 v4l2src device=/dev/video1 !
>> 'video/x-raw-yuv,width=640,height=480' ! ffmpegcolorspace ! xvimagesink
>>
>> And here is the command to capture audio
>>
>> gst-launch -e alsasrc device=hw:2,0 ! audioconvert ! lamemp3enc target=1
>> bitrate=128 cbr=true ! filesink location=audio.mp3
>>
>> But I get nothing from audio input. I can confirm that the card is working
>> just fine because the following command can capture video and audio
>> without
>> problem.
>>
>> mplayer -tv
>> driver=v4l2:input=1:device=/dev/video1:alsa=1:adevice=hw.1:immediatemode=0
>> tv:// -ao sdl
>>
>> This is audio capture card list in my system:
>>
>> **** List of CAPTURE Hardware Devices **** card 0: Intel [HDA Intel],
>> device
>> 0: ALC883 Analog [ALC883 Analog]
>>   Subdevices: 1/1
>>   Subdevice #0: subdevice #0
>> card 0: Intel [HDA Intel], device 1: ALC883 Digital [ALC883 Digital]
>>   Subdevices: 1/1
>>   Subdevice #0: subdevice #0
>> card 0: Intel [HDA Intel], device 2: ALC883 Analog [ALC883 Analog]
>>   Subdevices: 1/1
>>   Subdevice #0: subdevice #0
>> card 2: Cx231xxAudio [Cx231xx Audio], device 0: Cx231xx Audio [Conexant
>> cx231xx Capture]
>>   Subdevices: 1/1
>>   Subdevice #0: subdevice #0
>>
>> Any help would be appreciated.
>>
>> Regards
>>
>>
>>
>> --
>> View this message in context:
>>
>> http://gstreamer-devel.966125.n4.nabble.com/Unable-to-capture-audio-from-a-t
>> v-tuner-tp4658837.html
>> Sent from the GStreamer-devel mailing list archive at Nabble.com.
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>>
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>>
>
>
>
> --
> Edhoari Setiyoso
>



-- 
Edhoari Setiyoso
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