[PD] non-interpolating [vd~]
kyleklip at gmail.com
Tue May 16 18:30:25 CEST 2006
Oh man, thanks for the breakdown! I was trying to figure out how it
was working while futzing about with Paris' great experimental patches
a few weeks back. Impressed a bunch of friends, now I'm going to try
doing some "VJ-ing" for a show coming up.
Where can I find out more about this kind of stuff? I'd love to be
able to use live audio and project the FFT or even direct waveform
into the Gem window. Anybody done this yet?
On 5/15/06, Roman Haefeli <reduzierer at yahoo.de> wrote:
> hi paris
> what i can say from my experience (maybe wrong):
> - it seems that pix_pix2sig~ and pix_sig2pix~ follow the sample-by-pixel,
> respectively pixel-by-sample concept.
> - it seems that every audio-block refers to one frame of the videostream.
> - to synthesize a picture, you need to set a block~size higher/equal than
> the desired resolution. if blocksize is lower than the resolution, you won't
> get the whole frame converted to audio, respectively you can only draw a
> part of the frame with the audio signal
> - to choose freely the framerate of the videosynthesizer, the samplerate
> should be: framerate * blocksize
> - of course you could use also any audio-typical samplerate and set a higher
> samplerate in the processing subpatch by setting [block~], but then you have
> big quantization and maybe won't come close to the desired framerate.
> which settings worked for me?
> -i'm using a resolution of 160x120px, that are 19200px per frame -> i set
> blocksize to 32768.
> -i wanted to have a framerate of 25: 32768 * 25 = 819200 Hz
> i'm running it on winxp on a pentium m 1.7GHz and and my patch takes around
> 70% of my cpu, so this is almost the maximum i can work with in realtime.
> the problem with the resolution i use now, is that it has an overhead of 41%
> "Paris Treantafeles" <paris at parisgraphics.com> wrote:
> > Hi Roman,
> > Sorry to hijack your question with another question but...
> > I'm wondering when you use a high sample rate like this, what combination
> > of dimen message to pix_sig2pix~ and what block~ size do you use for best
> > results?
> > I'm guessing that there's some combination that is a good trade off
> > between smooth visuals and taking complete control of the cpu.
> > Thanks,
> > p
> > On May 15, 2006, at 6:16 AM, Roman Haefeli wrote:
> >> hi all
> >> i'm working on a project based on [pix_sig2pix~] and therefore i'm using
> >> a very high samplerate (819200) and a few [vd~]s. since [vd~] does
> >> interpolation, it uses a lot of cpu-power, though i would just need a
> >> delay~-object with audio-inlet, but without interpolation. is there such
> >> an external? or is there another cpu-friedly way of reading out from a
> >> delayline in audiorate?
> >> roman
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