Re: FEEDBACK CODE QUESTION

[Damian Stewart <damian@frey.co.nz>]

Ior Bock wrote:

> 1.) Do you know how the golden mean, phi comes into play with video 
> feedback, especially when we see TV feedback
> displaying the spiral / nautilus shell form ?

It doesn't.

> 2.) Is the feedback occuring within the mechanical circuity of the 
> feedback system a kind of resonance, and if so what exactly is it, what 
> is 'resonanting' and how?

If the feedback consists of a video camera pointed at a television (or a 
webcam pointed at its own preview window on a computer screen) the whole 
system of video camera, television, and light waves can be said to be 
the thing that is resonating.

> 3.) I'm hoping to emulate video feedback with software and am trying to 
> figure out basic algorithms that will let me do this,
> I recently posted the below detailed query to a Visual Basic programmers 
> forum, but it seems like there was little 'feedback'
> on this, can you offer any insights? Are there any code snippets 
> floating about that will let me do this that you may know of?
> (Please see below)

Digital video feedback usually involves getting access to the 
back-buffer, processing it somehow, and then blitting the processed 
image to the front-buffer. Google 'rotozoom', also check out 
http://www.piksel.no/pwiki/GePhex

Note that what makes analog video feedback different to digital video 
feedback is the kind of things it's very difficult to emulate digitally 
- namely the specific color response characteristics and geometry of the 
video camera and television.

You have actually played with a video camera and television, right? Or 
even a webcam and your computer monitor?

-- 
Damian Stewart
+64 27 305 4107

f r e y
live music with machines
http://www.frey.co.nz
http://www.myspace.com/freyed