Edge detection

iaften

Hello everyone

I need to add a button to a picture, so when i press it, it does edge detection on the image. I tried using convolution matrix but i could not get it to work..! Right now this is what i have for the first two buttons, and they work just fine:

PImage billed;
int aktueltFilter = -1;

void setup() {
  billed = loadImage("påfugl.jpg");
  size(billed.width, billed.height+50);
}

void draw() {  
    knap(0,"Stoej");
    knap(1,"Pixelering"); 
    knap(2, "EdgeDetection");
    if(aktueltFilter == 0){
      stoej();
    }else if(aktueltFilter == 1){
      pixelering();
    }else if(aktueltFilter == 2){
      EdgeDetection();
    }else{
      image(billed, 0, 0);
    }
}

void mouseClicked() {
      if(aktueltFilter == 0){
      stoej();
    }else if(aktueltFilter == 1){
      pixelering();
    }else if(aktueltFilter == 2){
      EdgeDetection();
    }else{
      image(billed, 0, 0);
    }
}    

void knap(int nr, String tekst){
  int knapBredde=100;
  int knapHoejde=20;
  int knapY=billed.height+10;

   fill(50);
   rect(nr * knapBredde+5, knapY, knapBredde, knapHoejde); 

   fill(255);
   text(tekst, nr * knapBredde+10, knapY+15);

   if(mousePressed == true
      && nr * knapBredde < mouseX 
      && mouseX < (nr+1) * knapBredde 
      && knapY < mouseY           
      && mouseY < knapY+knapHoejde)
   { 
     aktueltFilter = nr; 
   }
}


void stoej(){
  for(int y = 0; y < billed.height; y = y + 1){
    for(int x = 0; x < billed.width; x = x + 1){
      int nyX = x + int(random(10));
      color hentFarve = billed.get(nyX, y);
      set(x, y, hentFarve);
    }
  }
}

//Ændring af form
void pixelering(){
  int stoerrelse = 10;
  for(int y = 0; y < billed.height; y = y + stoerrelse){
    for(int x = 0; x < billed.width; x = x + stoerrelse){
      fill(billed.get(x, y));
      stroke(billed.get(x, y));
      rect(x, y, stoerrelse, stoerrelse);      
    }
  }
}

It looks like this:

Would really appreciate any help with adding this feature, since i have no idea what i am doing at this point..

Thanks - Iaften

koogs

please paste the code, not a screenshot of the code.

(after pasting, highlight the code and press ctrl-k to format it for the forum.)

iaften

Ok, thanks :)

koogs

I tried using convolution matrix but i could not get it to work

try again. use a convolution matrix. wikipedia has some example kernels for edge detection.

http://en.wikipedia.org/wiki/Kernel_(image_processing)

post an attempt at least. (and you'll get more replies if the variable names are in english)

bubber

hi

i'm struggling with the same project, can anyone help?

koogs

continued here:

http://forum.processing.org/two/discussion/5969/edge-detection-and-emboss