[linux-audio-dev] exploring LADSPA

Paul Davis paul at linuxaudiosystems.com
Thu Aug 14 01:39:00 UTC 2003


>>> and have done extensive benchmark tests and
>>> have found no degradation in performance
>
>> Yes. I believe double-precision is the standard data type used by most
>> floating-pt processors. Single-precision floats must first be converted to
>> doubles at each computation, thus actually degrading performance slightly.
>
>No difference according to my benchmarks - 0 difference

most other testers measure 6-8% on intel h/w (slower for doubles). you
have to be very careful that you are measuring two different
situations. automatic compiler conversions can make what appears to be
float math actually be double to start with.

>> I get a sense from postings to this list that this group is primarily
>> interested in real-time synthesis. RT doesn't interest me so much at this
>> time, partly because I'm running on a clunky old 400MHz machine, and

i routinely run RT synthesis code on my clunky old 450MHz machine :)

>and other controllers using (yuck) MIDI for now. LADSPA is interesting but
>I do not see where it handles some of the issues of polyphonic voicing
>and assignment control.

it doesn't. it was never meant to. attempts to create an API that did
do this led to discussions here (on LAD) about "XAP", but this has
just about all moved to the GMPI mailing list, where us LAD'ers get to
hang out and talk shop with the guys at Cakewalk, Adobe, FXpansion,
and several other companies who work on plugins and DAWs. devising
your own new API at this time is a bit like, err, err, i don't know
what its like but its like something.

>Do not be discouraged by those that tell you that we already did it and
>why don't you use that. They are missing the point, aren't they! 8^)

not missing the point. i welcome any and all developers to LAD and to
LADSPA. but those who don't know and understand history are condemned
to repeat it, and the linux world is full of repeated false starts
while all the time promising projects cry out for more assistance to
flesh them out.

--p "grumpy old man"




More information about the Linux-audio-dev mailing list