[linux-audio-dev] oss2jack 0.13: A kernel-based approach to using OSS applications with jackd

[guenter geiger]

On Mon, 23 Feb 2004, Kor Nielsen wrote:

> 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.

Looks pretty interesting. I have used LD_PRELOAD to implement libjackasyn,
but I could never get over some difficulties where it just failed to
preload. Have to check that out too ..

Guenter

> 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
>
>