Re: bin/56166: audioplay fails to play 24-bit wave files

[nia <nia%NetBSD.org@localhost>]

The following reply was made to PR bin/56166; it has been noted by GNATS.

From: nia <nia%NetBSD.org@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: bin/56166: audioplay fails to play 24-bit wave files
Date: Fri, 14 May 2021 16:22:15 +0000

 On Fri, May 14, 2021 at 03:20:01PM +0000, Michael van Elst wrote:
 > From: mlelstv%serpens.de@localhost (Michael van Elst)
 > To: gnats-bugs%netbsd.org@localhost
 > Cc: 
 > Subject: Re: bin/56166: audioplay fails to play 24-bit wave files
 > Date: Fri, 14 May 2021 15:15:35 -0000 (UTC)
 > 
 >  nia%pkgsrc.org@localhost writes:
 >  
 >  >audioplay expects to be able to pass the kernel audio stack raw 24-bit
 >  >PCM, but this doesn't work. the kernel only supports 8/16/32-bit PCM
 >  >PCM, so it fails with EINVAL.
 >  
 >  You could enable the 24bit code in the audio driver:
 >  
 >  /*    
 >   * Whether supports [US]LINEAR24/24 as userland format.
 >   */
 >  /* #define AUDIO_SUPPORT_LINEAR24 */
 >  
 >  
 
 I'm not sure the 24-bit format in the kernel is correct.
 
 Solaris does not natively handle 24-bit precision from
 userspace - https://illumos.org/man/7i/audio
 
 The OSS 24-bit format is packed into a 32-bit integer -
 http://manuals.opensound.com/developer/formats.html,
 while the format in the NetBSD kernel is purely 24-bit
 IIRC.
 
 I think it is better to use 32-bit to avoid ambiguity.