FAQ Search Today's Posts Mark Forums Read
» Video Reviews

» Linux Archive

Linux-archive is a website aiming to archive linux email lists and to make them easily accessible for linux users/developers.


» Sponsor

» Partners

» Sponsor

Go Back   Linux Archive > Redhat > Fedora User

 
 
LinkBack Thread Tools
 
Old 08-25-2008, 08:42 PM
Michael Schwendt
 
Default Format /dev/dsp expects?

On Mon, 25 Aug 2008 15:27:11 -0500, Mike McCarty wrote:

> Michael Schwendt wrote:
> > On Mon, 25 Aug 2008 14:26:25 -0500, Mike McCarty wrote:
> >
> >> Can anyone tell me what formats /dev/dsp, /dev/dsp56k,
> >> /dev/audio, etc. expect? It seems that I can copy
> >> a WAV format file directly to /dev/dsp and get recognizable
> >> sound. I wonder just what format they actually expect.
> >
> > /dev/audio used to accept µ-law encoding, /dev/dsp accepts raw pcm as
> > configured via ioctl. The device doesn't evaluate any WAV header.
>
> Thanks! So, if I want to use sox, I can specify the output to be
> /dev/dsp and raw, and the input format to be whatever corresponds.

Ask kernel devs whether you can still expect a specific raw format.

There are several parameters that must match: bits per sample,
signed/unsigned samples, number of channels (mono/stereo), frequency

Btw, it's likely that /dev/dsp will go away in the future, as it's
only a compatibility device file for the old OSS driver architecture
(unload a kernel module, and the device file is gone). ALSA uses
different device files.

--
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
 
Old 08-25-2008, 09:32 PM
Mike McCarty
 
Default Format /dev/dsp expects?

Michael Schwendt wrote:

Ask kernel devs whether you can still expect a specific raw format.

There are several parameters that must match: bits per sample,
signed/unsigned samples, number of channels (mono/stereo), frequency


Endianness?


Btw, it's likely that /dev/dsp will go away in the future, as it's
only a compatibility device file for the old OSS driver architecture
(unload a kernel module, and the device file is gone). ALSA uses
different device files.


Aha. So, what do you recommend? I was using my computer to generate
some reference signals for testing some other equipment.

Mike
--
p="p=%c%s%c;main(){printf(p,34,p,34);}";main(){pri ntf(p,34,p,34);}
Oppose globalization and One World Governments like the UN.
This message made from 100% recycled bits.
You have found the bank of Larn.
I speak only for myself, and I am unanimous in that!

--
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
 
Old 08-25-2008, 09:56 PM
Michael Schwendt
 
Default Format /dev/dsp expects?

On Mon, 25 Aug 2008 16:32:20 -0500, Mike McCarty wrote:

> > There are several parameters that must match: bits per sample,
> > signed/unsigned samples, number of channels (mono/stereo), frequency
>
> Endianness?

Add that to the list.

> Aha. So, what do you recommend? I was using my computer to generate
> some reference signals for testing some other equipment.

If you use sox already, use "play", sox's player.
I don't see why you insist on copying data to raw device files.

--
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
 
Old 08-25-2008, 10:16 PM
Mike McCarty
 
Default Format /dev/dsp expects?

Michael Schwendt wrote:

On Mon, 25 Aug 2008 16:32:20 -0500, Mike McCarty wrote:


There are several parameters that must match: bits per sample,
signed/unsigned samples, number of channels (mono/stereo), frequency

Endianness?


Add that to the list.


Aha. So, what do you recommend? I was using my computer to generate
some reference signals for testing some other equipment.


If you use sox already, use "play", sox's player.
I don't see why you insist on copying data to raw device files.


I don't insist on anything, and I'm not a regular sox user.
I had a need for some reference signals, and had a computer
sitting nearby, but no other signal generating equipment.
A thought occurred to me that I could probably get something
out of the computer with a little work. I fiddled around until
I got the thing to work. That's all.

If you know better ways, I'm willing to hear them.

Mike
--
p="p=%c%s%c;main(){printf(p,34,p,34);}";main(){pri ntf(p,34,p,34);}
Oppose globalization and One World Governments like the UN.
This message made from 100% recycled bits.
You have found the bank of Larn.
I speak only for myself, and I am unanimous in that!

--
fedora-list mailing list
fedora-list@redhat.com
To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-list
 

Thread Tools




All times are GMT. The time now is 11:56 PM.

VBulletin, Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2007, Crawlability, Inc.
Copyright 2007 - 2008, www.linux-archive.org