[fluxus] process and framedump sync

[Dave Griffiths]

> hi,
>
> after a few failed experiments trying to generate synced audiovisual
> matter
> using process, start-framedump and desired-fps, i was just wondering if
> there is
> a particular combination that is known to work well.

there is a little bit of maths required. you need to set the buffer size
to match the amount of audio samples per frame, given the fps of the video
you want to make, and the audio file.

so, say 25fps, with audio at 44100 samplerate, 44100/25 = 1764 samples per
frame.

set your jack and (start-audio) settings to this.

then all you need to do is make sure the calls to (process) and
(start-framedump) happen on the same frame

despite being assured otherwise, I am pretty positive that desiredfps has
no bearing on this.... all it does is keep track of the real clock time,
and throttle the renderer so it won't redraw any faster than the specified
framerate - as the audio source is not realtime, it doesn't matter how
fast or slow it generates the images.

you might have to make sure that no windows appear on top of the fluxus
window when you're doing this, (they might appear in the saved images) but
it depends on the driver you're using.

cheers,

dave