Subject: [linux-audio-dev] oss2jack 0.13: A kernel-based approach to using OSS applications with jackd
From: Kor Nielsen (korn-ml_AT_xdas.com)
Date: Tue Feb 24 2004 - 04:30:13 EET
Hi,
I have been quite frustrated with the difficulty of getting multiple OSS
applications using my sound hardware simultaneously. The LD_PRELOAD
hacks that I have tried leave much to be desired in terms of usability,
especially when dealing with arts and mozilla plugins.
oss2jack uses Jeremy Elson's useful fusd library
(http://www.circlemud.org/~jelson/software/fusd/) to create a userspace
character device, which is also a jackd client. It supports mono and
stereo streams, with virtually any sample rate thanks to libsamplerate
(http://www.mega-nerd.com/SRC/). Only the commonly-used OSS ioctls are
currently supported.
I have tested oss2jack with the following applications, and they behave
fairly well:
- mplayer
- artsd (and thus all the kde applications)
- xmms
- Macromedia Flash
TODO:
- support mmap for quake and other games
(requires support in fusd)
- detect jackd period for audio sync (currently assumes 64 samples).
Should not be too noticeable unless you get above a 256 sample
period)
- lower CPU usage with artsd by blocking until the minimum fragment
size is available (rather than the jackd period)
- support for the OSS mixer.
Available at:
http://fort.xdas.com/~kor/oss2jack/
WARNING: I have not yet tested oss2jack on the 2.4 series kernel.
Currently I am using a self-created 2.6 patch for fusd available at
the site above. It has been stable for the past 3 weeks on my machine,
but no guarantees about stability or safety... :)
fusd currently requires that devfs be enabled in the kernel.
Any comments are appreciated.
Kor
This archive was generated by hypermail 2b28 : Tue Feb 24 2004 - 04:36:18 EET