Pixel Sampling of video

advanced
#1

There is a particular effect I am trying to simulate

It involves first

1 sampling the brightness of pixels and then

2 creating particles whose behaviour is determined from #1

So I am focusing on the first step for now. Using OF how would you sample pixels in an efficient manner from a live webcam stream?

#2

Check out particles from color examples code, plenty available online.

To sample pixel brightness, see these examples, among others
/examples/video/videoGrabber
/examples/graphics/imageLoaderExample

particles!: GPU particle System with multitexturing and optical flow

<*o*>

#3

thanks. much appreciated

#4

If it is your webcam, you could write something like:

ofVideoGrabber cam;
ofPixels pixels;
cam.initGrabber(1200, 750);
cam.getTextureReference().readToPixels(pixels);
#5

the camera already has a pixels internally so you don’t need to readback from the texture which is really slow, you can cal:

cam.getPixels()
#6

cool, I didn’t know it