PathOfSight

I was curious as to whether anyone could help me with how to achieve this:

http://www.youtube.com/watch?v=ABqABv7MnmM&feature=player_embedded

I'm attempting something a little similar; though through use of cv.centroids.blobs rather than track(which appears to be what's used there). I need a way of subdividing areas within the jitter matrix so that I can use different areas from the video feed to control different parameters similar to what's shown above, but I have no idea of how to go about achieving the 'boxes'. Essentially I need a number of different sized/shaped regions from which i can individually extract xy data corresponding to the tracked object.

Alternatively, can this be done by overlaying/using another object (lcd?) & feeding it the xy data from blobs?

I've had a good browse of Jitter tutorials & have looked through a lot of help files, but apologies if I've missed something blindingly obvious somewhere...

I was curious as to whether anyone could help me with how to achieve this: 

Alternatively, can this be done by overlaying/using another object (lcd?) & feeding it the xy data from blobs? 

Any help would be hugely appreciated! :)


boxes-subdividing-jit-pwindow-adaptive-use-musical-instrument

using jit.iter you can get your x/y values from the tracking algorithm. the data manipulation and separation from these values (to set up your regions) could be handled using max objects such as [>] and [

for example if you have a 400x400 matrix and wish to only pass values when you are tracking in a square bounded by the center 100x100 pixels.

for x and y values, you apply [> 150] & [< 250] to effectively select only that area.

knowing the length in pixels of the edge of your jitter matrix (400), you can [* 0.5] it, giving you 200 (your center) and then [+] and [-] one variable to allow easy changing of the size of this selection.

if you wish to draw visual representation of your active area ontop of the tracking window, then i suppose you could either create a new simple jitter shape drawing patch with the shape on it to combine with your other jitter matrix or use an [LCD] object overlaid using the alpha channel. i think it may be better to represent it using the first method, as you shouldnt get resizing problems.

for example if you have a 400x400 matrix and wish to only pass values when you are tracking in a square bounded by the center 100x100 pixels.
for x and y values, you apply  [> 150] & [< 250] to effectively select only that area.
knowing the length in pixels of the edge of your jitter matrix (400), you can [* 0.5] it, giving you 200 (your center) and then [+] and [-] one variable to allow easy changing of the size of this selection.

Ta, I've already done the first part of that; [] objects combined with [scale] to allow me to retrieve data from specifically defined regions. Rather than using [LCD] I've used sliders for visual representation; as mentioned I was thinking of investigating use of [LCD], but it'd be great to know how it was done in the vid above, as it seems to me they've used a far more efficient method...

So if anyone knows what that is, it'd be hugely appreciated :D

Else I guess I'll just get to work on using LCD...

So if anyone knows what that is, it'd be hugely appreciated :D
Else I guess I'll just get to work on using LCD...


I would turn your video into GL and use jit.gl.gridshape. To get your video input into GL land, the easiest way is to use jit.gl.videoplane. You can then draw scalable plane (or other) gridshapes on top of the video, or lines etc., with transparency (@blend_enable 1). These will draw very smoothly and efficiently.

For going back and forth between pixels and GL look to "worldtoscreen" and "screentoworld", or if you're not changing the overall scene size, use an appropriate [scale] function.

GL takes some time to wrap your head around it (I think mine is only about a quarter there after many many hours) but it's soooo worth it. You'll get all kinds of other cool ideas for features...

'boxes' subdividing jit.pwindow? - 'Adaptive Use Musical Instrument'