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Multimedia/Discussion/General/playing two wav files simultaneously/List of Posts
Forum Topic - playing two wav files simultaneously: (9 Items)
   
Update
Ramesh Vemula(deleted)
06/05/2012 9:18 AM
post93514
playing two wav files simultaneously   
While playing a wav audio file with MME, is it possible to pause the play, then play a wav audio file using the "wave" 
utility?. Using the wave utility two wav files can be played simultaneously, but If I played one wav file via MME, then 
try to play a second wav file using the wave utility, it failed as follows:

SampleRate = 22050, Channels = 1, SampleBits = 8
snd_pcm_plugin_params failed: Invalid atgument 

What could be the reason for this error?.
Gilles Roy
06/05/2012 10:48 AM
post93518
Re: playing two wav files simultaneously   
We might need more logs. It sounds like the MME is not using a mixer
(hardware or software) device. If you want multiple connections to the
audio device you need to use the software mixer, this should allow the
scenario you listed to work.

Can you post the output of:
ls -al /dev/snd

And also post the contents of mme_data.sql?


Thanks,
Gilles
Ramesh Vemula(deleted)
06/07/2012 5:44 AM
post93568
Re: playing two wav files simultaneously   
Hi Gilles,

Please find attached mme_data.sql. 

output of ls -al /dev/snd:

total 0
-rw-rw-rw-  1 root      root              0 May 13  2011 controlC0
-rw-rw-rw-  1 root      root              0 May 13  2011 mixerC0D0
-rw-rw-rw-  1 root      root              0 May 18 15:22 pcmC0D0c
-rw-rw-rw-  1 root      root              0 May 18 15:22 pcmC0D0p
-rw-rw-rw-  1 root      root              0 May 18 15:22 pcmC0D1c
-rw-rw-rw-  1 root      root              0 May 18 15:22 pcmC0D1p
-rw-rw-rw-  1 root      root              0 May 13  2011 pcmC0D2p
lrw-rw-rw-  1 root      root              0 May 18 15:22 pcmPreferredc -> pcmC0D0c
lrw-rw-rw-  1 root      root              0 May 18 15:22 pcmPreferredp -> pcmC0D2p
Attachment: Text mme_data.sql 23.82 KB
Gilles Roy
06/07/2012 10:59 AM
post93572
Re: playing two wav files simultaneously   
I think I see the problem. In mme_data.sql you have:
INSERT INTO outputdevices(type, permanent, name, devicepath) VALUES(1, 1,
'output1', 'snd:/dev/snd/pcmC0D0p');

This means MME will use pcmC0D0p.


But wave will use pcmPreferredp, which points to:
 pcmPreferredp -> pcmC0D2p


pcmC0D2p is your software mixer. If you change MME to use pcmPreferredp or
pcmC0D2p it should be able to concurrently playback with the wave utility.


Regards,
Gilles
Ramesh Vemula(deleted)
06/14/2012 6:01 AM
post93656
Re: playing two wav files simultaneously   
Thanks Gilles, it solved the problem. However customer wants to have both outputs behave in the same manner. For example
, if output1 is playing a track session and output2 is playing another track session (both via mme). And output1 is tied
 to the software mixer (pcmC0D2p), when I pause both outputs and play a wave file using the wave utility, output1 will 
work, but output2 will fail as it is not tied to a software mixer. They can't tie it to the same software mixer as 
output1 because they need to play different audio independently.

Is it possible to have two software mixers each tied to a dedicated output?.
Ryan Allen(deleted)
06/14/2012 7:49 AM
post93658
Re: playing two wav files simultaneously   
Ramesh,

Can you provide the output of "pidin -p io-audio arg" and "pidin -p io-audio mem", please?

Thank you,

--
Ryan J. Allen
QNX Software Systems

________________________________
From: "Ramesh Vemula" <community-noreply@qnx.com>
To: "general-multimedia" <general-multimedia@community.qnx.com>
Sent: 14 June, 2012 6:01 AM
Subject: Re: playing two wav files simultaneously


Thanks Gilles, it solved the problem. However customer wants to have both outputs behave in the same manner. For example
, if output1 is playing a track session and output2 is playing another track session (both via mme). And output1 is tied
 to the software mixer (pcmC0D2p), when I pause both outputs and play a wave file using the wave utility, output1 will 
work, but output2 will fail as it is not tied to a software mixer. They can't tie it to the same software mixer as 
output1 because they need to play different audio independently.

Is it possible to have two software mixers each tied to a dedicated output?.




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General
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Attachment: HTML sf-attachment-mime2246 1.63 KB
Ramesh Vemula(deleted)
06/15/2012 4:55 AM
post93690
Re: playing two wav files simultaneously   
Ryan,

Please find attached output of the two commands you mentioned.
Attachment: Text io-audio.txt 1.09 KB
Ryan Allen(deleted)
06/18/2012 4:53 PM
post93745
Re: playing two wav files simultaneously   
Ramesh,

The intel_hda driver only creates a mixer for one playback device.  If you
want a mixer for both devices you'll have to create a PR for this.
Without a mixer on both devices you will always be limited to one process
sending audio to one of the playback devices.

-- 
Ryan J. Allen
QNX Software Systems
Ramesh Vemula(deleted)
06/20/2012 1:37 AM
post93778
RE: playing two wav files simultaneously   
Thanks Ryan.

-----Original Message-----
From: Ryan Allen [mailto:community-noreply@qnx.com] 
Sent: Tuesday, June 19, 2012 5:50 AM
To: general-multimedia@community.qnx.com
Subject: Re: playing two wav files simultaneously

Ramesh,

The intel_hda driver only creates a mixer for one playback device.  If you want a mixer for both devices you'll have to 
create a PR for this.
Without a mixer on both devices you will always be limited to one process sending audio to one of the playback devices.

--
Ryan J. Allen
QNX Software Systems





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General
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