blobs.pde

A java based programming environment - processing - free from processing.org. here it uses a free l

import hypermedia.video.*;



OpenCV opencv;

int w = 320;
int h = 240;
int threshold = 80;

boolean find=true;

PFont font;

void setup() {

    size( w*2+30, h*2+30 );

    opencv = new OpenCV( this );
    opencv.capture(w,h);
    
    font = loadFont( "AndaleMono.vlw" );
    textFont( font );

    println( "Drag mouse inside sketch window to change threshold" );
    println( "Press space bar to record background image" );

}



void draw() {

    background(0);
    opencv.read();
    //opencv.flip( OpenCV.FLIP_HORIZONTAL );

    image( opencv.image(), 10, 10 );	            // RGB image
    image( opencv.image(OpenCV.GRAY), 20+w, 10 );   // GRAY image
    image( opencv.image(OpenCV.MEMORY), 10, 20+h ); // image in memory

    opencv.absDiff();
    opencv.threshold(threshold);
    image( opencv.image(OpenCV.GRAY), 20+w, 20+h ); // absolute difference image


    // working with blobs
    Blob[] blobs = opencv.blobs( 100, w*h/3, 20, true );

    noFill();

    pushMatrix();
    translate(20+w,20+h);
    
    for( int i=0; i<blobs.length; i++ ) {

        Rectangle bounding_rect	= blobs[i].rectangle;
        float area = blobs[i].area;
        float circumference = blobs[i].length;
        Point centroid = blobs[i].centroid;
        Point[] points = blobs[i].points;

        // rectangle
        noFill();
        stroke( blobs[i].isHole ? 128 : 64 );
        rect( bounding_rect.x, bounding_rect.y, bounding_rect.width, bounding_rect.height );


        // centroid
        stroke(0,0,255);
        line( centroid.x-5, centroid.y, centroid.x+5, centroid.y );
        line( centroid.x, centroid.y-5, centroid.x, centroid.y+5 );
        noStroke();
        fill(0,0,255);
        text( area,centroid.x+5, centroid.y+5 );


        fill(255,0,255,64);
        stroke(255,0,255);
        if ( points.length>0 ) {
            beginShape();
            for( int j=0; j<points.length; j++ ) {
                vertex( points[j].x, points[j].y );
            }
            endShape(CLOSE);
        }

        noStroke();
        fill(255,0,255);
        text( circumference, centroid.x+5, centroid.y+15 );

    }
    popMatrix();

}

void keyPressed() {
    if ( key==' ' ) opencv.remember();
}

void mouseDragged() {
    threshold = int( map(mouseX,0,width,0,255) );
}

public void stop() {
    opencv.stop();
    super.stop();
}