Framerate in live video delay project : Ed Tannenbaum, Recollections

Processing Project Guidance
14

Try to make a first implementation of your first point ( crop PImage), but it actually make the frameRate drop dramatically (less than 10 fps).
Perhaps the idea is good but not my implementationā€¦:wink:

class User {
  PImage bodyImg; 
  ArrayList<NewImg> imgList; 
  PGraphics pgTotal; 
  User() {
    imgList = new ArrayList<NewImg>();
    pgTotal=createGraphics(512, 424);
  }

  void delayEffect() {
    createWhiteAndTransparentImage();
    colorAllPg();
  }

  void createWhiteAndTransparentImage() {
    bodyImg.filter(THRESHOLD); 
    PGraphics pgWhite=createGraphics(512, 424); 
    pgWhite.beginDraw(); 
    pgWhite.background(255); 
    pgWhite.mask(bodyImg); 
    pgWhite.endDraw();
    NewImg newImg=new NewImg();
    newImg.trimImage(pgWhite); 
    imgList.add(0, newImg);
    if (imgList.size()>100)imgList.remove(imgList.size()-1);
  }

  void colorAllPg() {
    pgTotal.beginDraw(); 
    pgTotal.clear(); 
    for (int i = imgList.size()-1; i > 0; i--) {
      PImage colorImg=imgList.get(i).img;
      pgTotal.tint(random(255), random(255), random(255)); 
      float x=imgList.get(i).cornerPos.x; 
      float y=imgList.get(i).cornerPos.y; 
      pgTotal.image(colorImg, x, y);
    }
    pgTotal.endDraw(); 
    image(pgTotal, 0, 0, width, height);
  }
}

class NewImg {
  PVector cornerPos; 
  PImage img; 
  NewImg () {
  }


  void trimImage(PImage image) {
    image.loadPixels(); 
    int width = image.width;
    int height = image.height;
    int left = 0;
    int top = 0;
    int right = width - 1;
    int bottom = height - 1;
    int minRight = width - 1;
    int minBottom = height - 1;

  top:
    for (; top < bottom; top++) {
      for (int x = 0; x < width; x++) {
        if (alpha(image.get(x, top)) != 0) {
          minRight = x;
          minBottom = top;
          break top;
        }
      }
    }

  left:
    for (; left < minRight; left++) {
      for (int y = height - 1; y > top; y--) {
        if (alpha(image.get(left, y)) != 0) {
          minBottom = y;
          break left;
        }
      }
    }

  bottom:
    for (; bottom > minBottom; bottom--) {
      for (int x = width - 1; x >= left; x--) {
        if (alpha(image.get(x, bottom)) != 0) {
          minRight = x;
          break bottom;
        }
      }
    }

  right:
    for (; right > minRight; right--) {
      for (int y = bottom; y >= top; y--) {
        if (alpha(image.get(right, y)) != 0) {
          break right;
        }
      }
    }
    cornerPos=new PVector(left, top); 
    img= image.get(left, top, right - left + 1, bottom - top + 1);
  }
}