Code that only displays the built-in camera in Processing

Rather than Processing, it's no longer just java

After posting, I noticed that the contents of Mat will be negative, so I should have used an int array instead of a byte array ... Mat.get () is overloaded ...

import org.opencv.core.*;
import org.opencv.highgui.*;

VideoCapture capture;

void setup(){  
  System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
  capture = new VideoCapture(0);
  fullScreen();
}

void draw(){
  background(0);
   if (capture.isOpened()) {
      Mat video = new Mat();
      capture.read(video);
      
      byte [] b;
      b = new byte[(int)video.size().height * (int)video.size().width*3];
      
      video.get(0,0,b);
      PImage img = createImage((int)video.size().width,(int)video.size().height,ARGB);
      
      for(int i=0;i<(int)video.size().width;i++){
        for(int j=0;j<(int)video.size().height;j++){
          int p = (i+j*(int)video.size().width)*3;
          img.set(i,j,color(fix(b[p+2]),fix(b[p+1]),fix(b[p+0])));
        }
      }
      image(img, 0, 0, (int)video.size().width, (int)video.size().height);
    } 
}

int fix(int val){
  if(val>-1)return val;
  else{
    return 256+val;
  }
}

reference -Basic processing of cv :: Mat ・ Using OpenCV with Qiita Processing (continued)