[xine-user] Re: downmixing from 48k to 44k with oss?

[Bill F. <bil...@mi...>]

On 10/10/2001, Adam Megacz wrote:

> Hey guys, I'm using the OSS sound drivers with xine/d4d, and a lot of
> my DVD's play without sound, logging errors about not being able to
> open the sound device at 48khz.
>
> Is there a way to make xine downmix to 44k, or get the OSS drivers to
> do this? Would upgrading to ALSA help?

Hi Adam,

Actually, there is a configuration parameter which can be defined in
config.h called FORCE_44K_MAX, which if set to a non-zero value will
force the audio rate to 44.1 KHz, but which is only normally defined
for PPC systems.  This was put in for the PPC, because the PPC OSS audio
driver was braindead and did not properly communicate back to the xine
application that it couldn't handle 48 KHz.  This isn't normally required
since if xine is properly told that the audio driver can't handle 48 KHz,
it will automatically fall back to 44.1 KHz.

Even for PPC, I'm thinking of changing this to a runtime configuration
variable that could be defined in the user's .xinerc file, since:

	1.  The PPC OSS audio driver in newer Linux kernels now
	    properly communicates back its inability to handle
	    48 KHz, indicating it can do 44.1 KHz.

	2.  I believe newer PPC audio hardware can actually handle
	    48 KHz audio now.

	3.  It would generally be more useful as a runtime configuration
	    variable, and could be used in other situations of braindead
	    OSS audio drivers.

Once my current non-realtime audio/video synchronization patch has been
committed, and I have a little spare time, I'll try and work up a small
patch to make this change.

						-Bill