Hullo, I've been tinkering with the Alsa library api and C++ dsp for some time now. Up to now I have used temporary files stored on a tmpfs when working with samples (not individual samples, 'samples' that are 30 seconds of music etc.). I had originally planned to try and implement some sort of real time audio processing. I decided to try jack, updated my kernel to 2.6.12 and added a few low latency/real time scheduling patches. I could not get jack to work right, I could get the latency down to about 10.8 ms but the signal is so corrupt as to be totally unuseable (any lower and xruns wipe out all audio). Would there be any benefit in attempting to right my own assembly ISR to retrieve sound data for processing. I have done some assembly in my undergraduate years (not real world assembly embedded in C or the like, more simple algorithms developed and optimized on toy processors) and had some sucess with writing reasonably fast assembly code but I'm not sure it's worth the effort. Is jack a good indication of real time processing possibilities for my particular set up or could a few tightly rolled assembly routines make all the difference? If anyone who has some experience in this particular area could offer an educated opinion that'd be great. Cathal
Alsa Library api vs. ISR
Started by ●August 2, 2005
Reply by ●August 2, 20052005-08-02
Instead of dealing with interrupts, you might write plugins for a LADSPA host. Also take a look at graphical languages like Pure Data or jMax where you can build a realtime DSP graph and write extension blocks of your own. http://www.ladspa.org/ http://www-crca.ucsd.edu/~msp/software.html http://freesoftware.ircam.fr/rubrique.php3?id_rubrique=14 Martin -- Quidquid latine dictum sit, altum viditur.