slow scan television anybody?

id love to know as well. I attempted to model a crt's scanning method
with jit.poke~ and peek~, and wanted to turn the argb color signals
into a 'composite' style audio signal which could then be manipulated
by msp~ style effects.

I could not get my peek and poke to 'sync' properly to draw frame of
color. Id love to know some approaches to this.

id imagine youd have to poke~ and peek~ from msp~ to jitter (well,
duh) and use some phasors to drive them as a sync signal. this was a
rough patch/idea trying to draw a frame of red with poke and peek.


On May 9, 2007, at 1:39 PM, Doug Goodwin wrote:

> Friends,
>
> I would like to broadcast images via modulated sound using an approach
> slow-scan television or sstv. The procedure will go something like
> this:
>
>     img snap -> matrix (320x240) -> fm ->
>      --acoustic transmission--
>     -> demodulator -> matrix -> pwindow
>
> Yes, I'm inviting noise to enter the transmission and distort the
> image before it is rendered in the pwindow.
>
> Has anybody done this before--do you have any tips for me?
>
> Thanks in advance,
> -Doug
>
>
> ps: You can read about sstv on wikipedia
> don't miss the part about xmissions from the moon!
>
> Here is some pertinent information about how the image matrix is
> encoded:
>
> The transmission consists of horizontal lines, scanned from left to
> right. The modulating frequency changes between 1500 and 2300 Hz,
> corresponding to the intensity (brightness) of the color component.
> The modulation is analogue, so there is not a defined number of pixels
> in each line; they can be sampled using any rate (though in practice,
> the image aspect ratio is conventionally 4:3). Lines end in a 1200 Hz
> horizontal synchronization pulse of 5 milliseconds.

v a d e //

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