blob detection code

1. //---------------------------------------------------------
//
// author: thomas diewald
// date: 06.09.2011
//
// example how to use diewald_CV_kit.blobdetection.
//
// -------------------------------------------------------
// interaction:
//
// mouseX - defines the brightness treshhold
// dragged mouse - drag a rectangle to define the detection area
//
// key 'UP' - lower resolution
// key 'DOWN' - higher resolution
// key 'b' - draw boundingsboxes of blobs
// key 'f' - fill blobs
//---------------------------------------------------------
import diewald_CV_kit.libraryinfo.*;
import diewald_CV_kit.utility.*;
import diewald_CV_kit.blobdetection.*;
import java.util.ArrayList;
PFont font;
PImage sample_img;
int size_x, size_y;
BlobDetector blob_detector;
BoundingBox detection_area;
int detection_resolution = 1;
boolean draw_blobs_boundingsbox = true;
boolean draw_filled_blobs = true;
public void setup() {
size(640, 480);
// sample_img = loadImage(image_path + "imageprocessing_gradient_v7_600x600.jpg");
sample_img = loadImage("imageprocessing_gradient_v9_640x480.jpg");
size_x = sample_img.width;
size_y = sample_img.height;
//size(size_x, size_y);
size(640, 480);
sample_img.loadPixels();
blob_detector = new BlobDetector(size_x, size_y);
blob_detector.setResolution(detection_resolution);
blob_detector.computeContours(true);
blob_detector.computeBlobPixels(!true);
blob_detector.setMinMaxPixels(10*10, size_x*size_y);
blob_detector.setBLOBable(new BLOBable_GRADIENT(this, sample_img));
detection_area = new BoundingBox(0, 0, size_x, size_y);

2. blob_detector.setDetectingArea(detection_area);
font = createFont("Calibri", 14);
textFont(font);
frameRate(200);
}
public void draw() {
background(255);
image(sample_img, 0, 0);
// draw the detection-area
stroke(0, 0, 0);
strokeWeight(1);
noFill();
rect(detection_area.xMin(), detection_area.yMin(), detection_area.xSize()-1,
detection_area.ySize()-1);
// set resolution - improves speed a lot
blob_detector.setResolution(detection_resolution);
//update the blob-detector with the new pixelvalues
blob_detector.update();
// get a list of all the blobs
ArrayList<Blob> blob_list = blob_detector.getBlobs();
// iterate through the blob_list
for (int blob_idx = 0; blob_idx < blob_list.size(); blob_idx++ ) {
// get the current blob from the blob-list
Blob blob = blob_list.get(blob_idx);
// get the list of all the contours from the current blob
ArrayList<Contour> contour_list = blob.getContours();
// iterate through the contour_list
for (int contour_idx = 0; contour_idx < contour_list.size(); contour_idx++ ) {
// get the current contour from the contour-list
Contour contour = contour_list.get(contour_idx);
// get the current boundingbox from the current contour
BoundingBox bb = contour.getBoundingBox();
// handle the first contour (outer contour = contour_idx == 0) different to the inner contours
if ( contour_idx == 0) {
// draw the boundingbox and blob-id as text
if ( draw_blobs_boundingsbox ) {
drawBoundingBox(bb, color(0, 200, 200), 1);

3. fill(0, 200, 200);
text("blob["+blob_idx+"]", bb.xMin(), bb.yMin()- textDescent()*2);
}
// draw the contour
drawContour(contour.getPixels(), color(255, 0, 0), color(255, 0, 255, 100), draw_filled_blobs,
1);
}
else {
// draw the inner contours, if they have more than 20 vertices
if ( contour.getPixels().size() > 20) {
drawContour(contour.getPixels(), color(255, 150, 0), color(0, 100), false, 1);
}
}
}
}
// simple information about framerate, and number of detected blobs
fill(0, 200);
noStroke();
rect(0, 0, 150, 50);
printlnNumberOfBlobs(blob_detector);
printlnFPS();
}