Calibrate works?

lib/opencv_processing/examples/WarpPerspective/WarpPerspective.pde

@@ -0,0 +1,76 @@
+import gab.opencv.*;
+import org.opencv.imgproc.Imgproc;
+import org.opencv.core.MatOfPoint2f;
+import org.opencv.core.Point;
+import org.opencv.core.Size;
+
+import org.opencv.core.Mat;
+import org.opencv.core.CvType;
+
+
+OpenCV opencv;
+PImage src;
+PImage card;
+int cardWidth = 250;
+int cardHeight = 350;
+
+Contour contour;
+
+void setup() {
+  src = loadImage("cards.png");
+  size(src.width + cardWidth, src.height);
+  opencv = new OpenCV(this, src);
+
+  opencv.blur(1);
+  opencv.threshold(120);
+
+  contour = opencv.findContours(false, true).get(0).getPolygonApproximation();
+
+  card = createImage(cardWidth, cardHeight, ARGB);  
+  opencv.toPImage(warpPerspective(contour.getPoints(), cardWidth, cardHeight), card);
+}
+
+Mat getPerspectiveTransformation(ArrayList<PVector> inputPoints, int w, int h) {
+  Point[] canonicalPoints = new Point[4];
+  canonicalPoints[0] = new Point(w, 0);
+  canonicalPoints[1] = new Point(0, 0);
+  canonicalPoints[2] = new Point(0, h);
+  canonicalPoints[3] = new Point(w, h);
+
+  MatOfPoint2f canonicalMarker = new MatOfPoint2f();
+  canonicalMarker.fromArray(canonicalPoints);
+
+  Point[] points = new Point[4];
+  for (int i = 0; i < 4; i++) {
+    points[i] = new Point(inputPoints.get(i).x, inputPoints.get(i).y);
+  }
+  MatOfPoint2f marker = new MatOfPoint2f(points);
+  return Imgproc.getPerspectiveTransform(marker, canonicalMarker);
+}
+
+Mat warpPerspective(ArrayList<PVector> inputPoints, int w, int h) {
+  Mat transform = getPerspectiveTransformation(inputPoints, w, h);
+  Mat unWarpedMarker = new Mat(w, h, CvType.CV_8UC1);    
+  Imgproc.warpPerspective(opencv.getColor(), unWarpedMarker, transform, new Size(w, h));
+  return unWarpedMarker;
+}
+
+
+void draw() {
+  image(src, 0, 0);
+  noFill(); 
+  stroke(0, 255, 0); 
+  strokeWeight(4);
+  contour.draw();
+  fill(255, 0);
+  ArrayList<PVector> points = contour.getPoints();
+  for (int i = 0; i < points.size(); i++) {
+    text(i, points.get(i).x, points.get(i).y);
+  }
+
+  pushMatrix();
+  translate(src.width, 0);
+  image(card, 0, 0);
+  popMatrix();
+}
+