How to get average color of pixels from video frames?

Core Library Questions

entite.ab

How to get average color of pixels from video frames?

in Core Library Questions • 2 years ago

Hi!

I wonder how to get and display the average color between the frames of a movie on the one hand, and my webcam on the other hand.

I have tried to use Ben Fry's ColorSorting Example but couldn't make it work for both videos: only for the cam.

I know there must be a problem in my sketch but I am so unfamiliar with coding...

void draw() {
if (myMovie.available()) {
myMovie.read();
background(0);
noStroke();
int index = 0;
int rtot = 0;
int gtot = 0;
int btot = 0;
for (int j = 0; j < myMovie.height; j += increment) {
for (int i = 0; i < myMovie.width; i += increment) {
int pixelColor = myMovie.pixels[j*myMovie.width + i];
int r = (pixelColor >> 16) & 0xff;
int g = (pixelColor >> 8) & 0xff;
int b = pixelColor & 0xff;
rtot = rtot + r;
gtot = gtot + g;
btot = btot + b;
index++;
}
}
}
if (myCapture.available()) {
myCapture.read();
background(0);
noStroke();
int index = 0;
int rtot = 0;
int gtot = 0;
int btot = 0;
for (int j = 0; j < myCapture.height; j += increment) {
for (int i = 0; i < myCapture.width; i += increment) {
int pixelColor = myCapture.pixels[j*myCapture.width + i];
int r = (pixelColor >> 16) & 0xff;
int g = (pixelColor >> 8) & 0xff;
int b = pixelColor & 0xff;
rtot = rtot + r;
gtot = gtot + g;
btot = btot + b;
index++;
}
}
rtot = rtot/index;
gtot = gtot/index;
btot = btot/index;
myColor = color(rtot,gtot,btot);
fill(myColor);
rect(0,0,w,h);
// Faster method of displaying pixels array on screen
image(myMovie,0,0,myMovie.width/4,myMovie.height/4);
image(myCapture,100,0,myCapture.width/4,myCapture.height/4);
}
}

Can anybody help me? I am quite in a hurry right now and almost having a nervous breakdown;)

Thanks a lot

Replies(1)

PhiLho

Re: How to get average color of pixels from video frames?

2 years ago

Avoid making duplicate threads, please, you can bump a topic by self-replying or editing the message. I deleted the previous message and moved this one to Core Libraries section, as we can't test it without the movie library (and a webcam!). (Hence, probably, the lack of answers.)

But a quick look at the code might show at least one issue: you redeclare index and totals in the capture part, masking the previous variables of same name, so you don't update the latter.
Oh, and to be safe, I would declare the various 'tot' variables as long instead of int, so there is less risk of overflow.

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