[linux-audio-dev] TiMidity as a CPU hog

Robert Jonsson rj at spamatica.se
Fri Jun 11 11:10:17 UTC 2004


Hi,

On Friday 11 June 2004 11.26, Jens M Andreasen wrote:
> Hi Dave, Takashi!
>
> I've got timidity up and running now, as a server under OSS. Made me
> self a new option to read directly from /dev/sequencer2 (The
> documentation says the input format should be similar to /dev/sequencer,
> but that's wrong.)
>
> The first note I play actually happens, and resembles an acoustic piano
> with a bit of wobbly reverb. So far so good ...
>
> The problem is that it stops rendering as soon as I release the note and
> then only renders when there is new midi-input (as in massaging the
> modulation wheel like a mad man ...). I have tried turning active
> sensing ON on my keyboard to no avail.
>
> Then I started to look further into the sources in search for the actual
> synthesizer. There is some 3MB of cross-platform C-code and headers, and
> most of it is not what I'm looking for.
>
> So far I have only localized the soundfont loader and I am currently
> reading up on the struct that defines the format. If I can find (or if
> you can help me find?) the parts that actually assigns and renders a
> note, then I should be able to write a new CPU-friendly voice-assigner
>
> The goal would be to pruduce something like a tmdt--. That is to say:
> Timidity++ unbloated, a module which only includes the stuff needed to
> run as a softsynth under Linux.
>
> So, where is the damned synthesizer? :)

It's in there!  ;-}

Now, you might have already tried Fluidsynth, but I thought I would mention it 
for completeness.
Fluidsynth is also a soundfont player which "might" be more aimed at realtime 
synth.

It has it's own sets of problems though, none that really matter to me though, 
I think it's an excellent synth.


/Robert

ps.
As for the CPU hogging, fluidsynth had a problem earlier when the reverb was 
enabled. When there was little or none signal into the reverb it went totally 
bonkers and consumed pretty much all cpu (a denormal problem I seem to 
remember). 
So the obvious question is, when timidity consumes all cpu, is the reverb 
enabled?
ds.

>
> mvh // Jens M Andreasen
>
<...>
-- 
http://spamatica.se/music/



More information about the Linux-audio-dev mailing list