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FEEDBACK CODE QUESTION





Hi,

I'm hoping to find some answers to questions relating to video feedback.

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 ?

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?

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)

Best regards to you and thank you for any input you can offer

Ior

------------
Hi Folks,

Asking for help with trying to figure out a way to emulate simple tv video feedback with VB using simple graphics.

For this scenario I don't know where to begin though, am hoping for some thoughtful input, suggestions, and code samples to get me started would be a God send. Would prefer NOT using DirectX if possible, but just the plain simple graphics tools standard to VB 4.0, 5.0...

Have included a bunch of links to illustrate what I am looking for. Really what Im after is best represented in the very first link, and this is what I would like to replicate.

Would like to do this with integers being used as the feedback medium, in other words, for video feedback we have for example;

"Video Feedback is easy and fun for anyone with a video camera and a monitor (TV screen). To make the simplest kind, take the "video out" from the camera and plug it into the "video in" on the monitor, and then point the camera at the monitor, so the monitor displays a picture of the monitor. Now you have a video feedback loop! To get the effects demonstrated in the gallery, careful adjustments of the various knobs and dials on the camera and monitor are required. I also recommended that you get a tripod. This is especially useful for doing rotations, since the camera can be held at a fixed angle. Adjust the tripod so you can rotate the camera about the viewing axis."

so in the VB code, user inputs numbers into some text boxes and these serve as the "video in" and "video out" mechanisms, so through looped recursion;

do while loop_counter <> 5000
textbox1.text = 100 represents Camera video out
textbox2.text = 75 represents Monitor video in
var = new value + (textbox1.text + textbox2.text) recursion value
(code here generates graphic spiral )
loop

Following demonstrates what Im after exactly, note I'm not looking for a solution that needs to be really high fine complex graphics, etc - just want to demonstrate the basic concept. Would like the feedback generated however to be tied directly to the number inputs specifically though. Any help would be appreciated!

Cheers
------------------
P.S. - got the following response from a VB forum;

"Originally Posted by chemicalNova
In any way in VB, drawing the graphical spiral will be very very VERY slow.

Does it have to be literally the same as whats above? How about, for example, a PictureBox that acts as the screen (video out), and a PictureBox that acts as the camera (video in). The Screen picturebox has a mini version of the camera box, which holds the contents of the Screen Picturebox. Then, you could possibly give exact rotation angles, for the camera, and display it inside the screen picturebox."



DESCRIPTIVE LINKS on VIDEO FEEDBACK FOLLOW;
-------------
http://www.youtube.com/watch?v=2Jqm62IhLGM

http://www.videofeedback.dk/World/

http://www.archive.org/movies/thumbnails.php?identifier=HansLemursonDavidSkold
http://www.youtube.com/watch?v=RuHmtSGbD8s

http://www.youtube.com/watch?v=2Jqm62IhLGM
http://www.archive.org/movies/thumbnails.php?identifier=HansLemursonDavidSkold
http://www.youtube.com/watch?v=RuHmtSGbD8s



http://www.youtube.com/results?search_type=search_videos&search_query=feedback&search_sort=&search_category=26

http://members.tripod.com/professor_tom/galleries/video/mixer/mixer4.html
http://members.tripod.com/professor_tom/galleries/video/mixer/mixer5.html
http://www.videofeedback.dk/World/
http://nyfilmvideo.com/sep2002/screen4.htm
=====
Space-Time Dynamics in Video Feedback James P. Crutchfield Video feedback provides a readily available experimental system to study complex spatial and temporal dynamics. This article outlines the use and modeling of video feedback systems. It

http://www.youtube.com/results?search_type=search_videos&search_query=feedback&search_sort=&search_category=26

MediaSculp - Gallery
http://www.mediasculp.com/QTVR/
http://www.mediasculp.com/Gallery/videofeedback/index.htm
http://www.videofeedback.dk/vf/oversigt.html
http://www.videofeedback.com/
http://www.art.pdx.edu/faculty/facultyhome/pirofsky/digital_stupa/digitalstupa.html




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