Face and Eye Tracking Fun!

I recently discovered the openframeworks toolkit. It is an open source C++ toolkit that wraps together many commonly used libraries for simple and fast experimentation. I absolutely love it!

When I shared code in the past, it took quite a bit of time to document what libraries, which version, and sometimes (even with C++) which operating system the new user must install for the code to compile properly. With openframeworks, that annoyance is a thing of the past.

For this post I decided to make a quick and fun example adopted from one of openframeworks' provided examples on detecting faces in pictures. The example can be found under the folder: examples/addons/opencvHaarFinderExample.

I decided to extend their example to detect faces from a live webcam or a quicktime movie. I was amazed at how few lines of code it took. To get started, download the appropriate toolkit for your IDE, here. Then copy the folder opencvHaarFinderExample in examples/addons/ to apps/myApps/. Then replace the code in testApp.cpp with the following:
#include "testApp.h" //-------------------------------------------------------------- void testApp::setup(){ camWidth = 480; camHeight = 360; //uncomment and comment lines below to test different detectors finder.setup("haarcascade_frontalface_default.xml"); //finder.setup("haarcascade_frontalface_alt.xml"); //finder.setup("haarcascade_frontalface_alt2.xml"); //finder.setup("haarcascade_eyeglasses.xml"); //finder.setup("haarcascade_eye.xml"); #ifdef _USE_LIVE_VIDEO VideoGrabber.setVerbose(true); VideoGrabber.initGrabber(camWidth,camHeight,OF_IMAGE_COLOR); colorImg.allocate(camWidth,camHeight,OF_IMAGE_COLOR); #else VideoPlayer.loadMovie("ThemeFromShaft.mov"); VideoPlayer.play(); #endif } //-------------------------------------------------------------- void testApp::update(){ ofBackground(100,100,100); bool newFrame = false; #ifdef _USE_LIVE_VIDEO VideoGrabber.grabFrame(); newFrame = VideoGrabber.isFrameNew(); #else VideoPlayer.idleMovie(); newFrame = VideoPlayer.isFrameNew(); #endif if (newFrame){ #ifdef _USE_LIVE_VIDEO colorImg.setFromPixels(VideoGrabber.getPixels(), camWidth, camHeight, OF_IMAGE_COLOR); #else colorImg.setFromPixels(VideoPlayer.getPixels(), camWidth, camHeight, OF_IMAGE_COLOR); #endif finder.findHaarObjects(colorImg); } } //-------------------------------------------------------------- void testApp::draw(){ ofSetHexColor(0xffffff); colorImg.draw(0,0); ofNoFill(); for(int i = 0; i < finder.blobs.size(); i++) { ofRectangle dim = finder.blobs[i].boundingRect; ofRect(dim.x, dim.y, dim.width, dim.height); } ofSetHexColor(0xffffff); char reportStr[1024]; sprintf(reportStr, "Number Detected: %lu fps: %f", finder.blobs.size(), ofGetFrameRate()); ofDrawBitmapString(reportStr, 20, 20+camHeight); } //-------------------------------------------------------------- void testApp::keyPressed (int key){ switch (key){ case ' ': break; } } //-------------------------------------------------------------- void testApp::mouseMoved(int x, int y ){ } //-------------------------------------------------------------- void testApp::mouseDragged(int x, int y, int button){ } //-------------------------------------------------------------- void testApp::mousePressed(int x, int y, int button){ } //-------------------------------------------------------------- void testApp::mouseReleased(int x, int y, int button){ } //-------------------------------------------------------------- void testApp::windowResized(int w, int h){ } Then replace the code in testApp.h with the following:
#ifndef _TEST_APP #define _TEST_APP #include "ofMain.h" #include "ofxCvHaarFinder.h" #define _USE_LIVE_VIDEO //comment to use video, uncomment to use webcam class testApp : public ofBaseApp{ public: void setup(); void update(); void draw(); void keyPressed (int key); void mouseMoved(int x, int y ); void mouseDragged(int x, int y, int button); void mousePressed(int x, int y, int button); void mouseReleased(int x, int y, int button); void windowResized(int w, int h); int camWidth, camHeight; #ifdef _USE_LIVE_VIDEO ofVideoGrabber VideoGrabber; #else ofVideoPlayer VideoPlayer; #endif ofxCvHaarFinder finder; ofImage colorImg; }; #endif For those mac users out there, just download this, open /apps/myApps/HeadTracking/TrackingExample.xcodeproj in Xcode (3.2 and above) and hit run!