frame_extraction.pde

import gab.opencvpro.*;
import org.opencv.imgproc.Imgproc;
import org.opencv.core.Core;
import org.opencv.core.Mat;
import org.opencv.core.CvType;

import org.opencv.core.MatOfPoint;
import org.opencv.core.Point;

import java.awt.Rectangle;

OpenCVPro opencv;
PImage src, dst;


int searchColumn = 70;

int distanceBetweenSprockets = 32;


ArrayList<MatOfPoint> contours;

class Sprocket{
  int top;
  int bottom;
  
  Sprocket(int top, int bottom){
    this.top = top;
    this.bottom = bottom;
  }
}

ArrayList<Sprocket> sprockets;

Rectangle roi;
void setup() {
  src = loadImage("_MG_9847.JPG");
  src.resize(500, 0);

  size(src.width*2, src.height);

  roi = new Rectangle(0, 270, src.width, 300);

  opencv = new OpenCVPro(this, src.width, src.height);
  opencv.loadImage(src);
  opencv.gray();

  Mat grayMat = opencv.getBufferGray();
  Mat roiMat = grayMat.submat(roi.y, roi.y+roi.height, roi.x, roi.x+roi.width );
  opencv.setBufferGray(roiMat);

  opencv.findSobelEdges(0, 2);
  opencv.threshold(50);

  dst = createImage(src.width, src.height, ARGB);
  opencv.toPImage(opencv.getBufferGray(), dst);

  
  ArrayList<Integer> sprocketEdges = new ArrayList<Integer>();
  
  for (int row = 1; row < dst.height; row++) {
    int prevI = searchColumn + (row-1)*dst.width;
    int thisI = searchColumn + row*dst.width;

    boolean thisRow = brightness(dst.pixels[thisI]) > 0 ;
    boolean prevRow = brightness(dst.pixels[prevI]) > 0;

    if (thisRow && !prevRow) {
      sprocketEdges.add(row);     
    }
  }
  
  sprockets = new ArrayList<Sprocket>();
  
  // loop over sprocketEdges and determine pairs
  for(int i = 1; i < sprocketEdges.size(); i++){
    int prev = sprocketEdges.get(i-1);
    int curr = sprocketEdges.get(i);
    
    if(abs(curr - prev) < distanceBetweenSprockets){
      sprockets.add(new Sprocket(prev, curr));
    }
  }

 // println(sprocketTops.size());
}

void drawContours(ArrayList<MatOfPoint> cntrs) {
  for (MatOfPoint contour : cntrs) {
    beginShape();
    Point[] points = contour.toArray();
    for (int i = 0; i < points.length; i++) {
      vertex((float)points[i].x, (float)points[i].y);
    }
    endShape();
  }
}

void draw() {
  image(src, 0, 0);
  image(dst, src.width, 0);
  //translate(src.width, 0);
  noFill();
  strokeWeight(4);

  stroke(255, 0, 0);
  rect(roi.x, roi.y, roi.width, roi.height);
  strokeWeight(1);

  stroke(0, 0, 255);
  translate(roi.x, roi.y);
  line(searchColumn, 0, searchColumn, src.height);


  for(Sprocket sprocket : sprockets){
      stroke(0, 255, 0);
    line(0, sprocket.top, src.width, sprocket.top);
      stroke(255, 0, 0);
    line(0, sprocket.bottom, src.width, sprocket.bottom);

  }

//  for (Integer row : sprocketTops) {
//    line(0, row, src.width, row);
//  }
//  
//    stroke(255, 0, 0);
//
//  for (Integer row : sprocketBottoms) {
//    line(0, row, src.width, row);
//  }

  //drawContours(contours);
}