OpenCV using C++

Author: rahulbordoloi

opencv.cpp

@@ -0,0 +1,119 @@
+// CPP program to detect face in a live video 
+  
+// Include required header files from OpenCV directory 
+#include "/usr/local/include/opencv2/objdetect.hpp" 
+#include "/usr/local/include/opencv2/highgui.hpp" 
+#include "/usr/local/include/opencv2/imgproc.hpp" 
+#include <iostream> 
+  
+using namespace std; 
+using namespace cv; 
+  
+// Function for Face Detection 
+void detectAndDraw( Mat& img, CascadeClassifier& cascade,  
+                CascadeClassifier& nestedCascade, double scale ); 
+string cascadeName, nestedCascadeName; 
+  
+int main( int argc, const char** argv ) 
+{ 
+    // VideoCapture class for playing video for which faces to be detected 
+    VideoCapture capture;  
+    Mat frame, image; 
+  
+    // PreDefined trained XML classifiers with facial features 
+    CascadeClassifier cascade, nestedCascade;  
+    double scale=1; 
+  
+    // Load classifiers from "opencv/data/haarcascades" directory  
+    nestedCascade.load( "../../haarcascade_eye_tree_eyeglasses.xml" ) ; 
+  
+    // Change path before execution  
+    cascade.load( "../../haarcascade_frontalcatface.xml" ) ;  
+  
+    // Start Video..1) 0 for WebCam 2) "Path to Video" for a Local Video 
+    capture.open(0);  
+    if( capture.isOpened() ) 
+    { 
+        // Capture frames from video and detect faces 
+        cout << "Face Detection Started...." << endl; 
+        while(1) 
+        { 
+            capture >> frame; 
+            if( frame.empty() ) 
+                break; 
+            Mat frame1 = frame.clone(); 
+            detectAndDraw( frame1, cascade, nestedCascade, scale );  
+            char c = (char)waitKey(10); 
+          
+            // Press q to exit from window 
+            if( c == 27 || c == 'q' || c == 'Q' )  
+                break; 
+        } 
+    } 
+    else
+        cout<<"Could not Open Camera"; 
+    return 0; 
+} 
+  
+void detectAndDraw( Mat& img, CascadeClassifier& cascade, 
+                    CascadeClassifier& nestedCascade, 
+                    double scale) 
+{ 
+    vector<Rect> faces, faces2; 
+    Mat gray, smallImg; 
+  
+    cvtColor( img, gray, COLOR_BGR2GRAY ); // Convert to Gray Scale 
+    double fx = 1 / scale; 
+  
+    // Resize the Grayscale Image  
+    resize( gray, smallImg, Size(), fx, fx, INTER_LINEAR );  
+    equalizeHist( smallImg, smallImg ); 
+  
+    // Detect faces of different sizes using cascade classifier  
+    cascade.detectMultiScale( smallImg, faces, 1.1,  
+                            2, 0|CASCADE_SCALE_IMAGE, Size(30, 30) ); 
+  
+    // Draw circles around the faces 
+    for ( size_t i = 0; i < faces.size(); i++ ) 
+    { 
+        Rect r = faces[i]; 
+        Mat smallImgROI; 
+        vector<Rect> nestedObjects; 
+        Point center; 
+        Scalar color = Scalar(255, 0, 0); // Color for Drawing tool 
+        int radius; 
+  
+        double aspect_ratio = (double)r.width/r.height; 
+        if( 0.75 < aspect_ratio && aspect_ratio < 1.3 ) 
+        { 
+            center.x = cvRound((r.x + r.width*0.5)*scale); 
+            center.y = cvRound((r.y + r.height*0.5)*scale); 
+            radius = cvRound((r.width + r.height)*0.25*scale); 
+            circle( img, center, radius, color, 3, 8, 0 ); 
+        } 
+        else
+            rectangle( img, cvPoint(cvRound(r.x*scale), cvRound(r.y*scale)), 
+                    cvPoint(cvRound((r.x + r.width-1)*scale),  
+                    cvRound((r.y + r.height-1)*scale)), color, 3, 8, 0); 
+        if( nestedCascade.empty() ) 
+            continue; 
+        smallImgROI = smallImg( r ); 
+          
+        // Detection of eyes int the input image 
+        nestedCascade.detectMultiScale( smallImgROI, nestedObjects, 1.1, 2, 
+                                        0|CASCADE_SCALE_IMAGE, Size(30, 30) );  
+          
+        // Draw circles around eyes 
+        for ( size_t j = 0; j < nestedObjects.size(); j++ )  
+        { 
+            Rect nr = nestedObjects[j]; 
+            center.x = cvRound((r.x + nr.x + nr.width*0.5)*scale); 
+            center.y = cvRound((r.y + nr.y + nr.height*0.5)*scale); 
+            radius = cvRound((nr.width + nr.height)*0.25*scale); 
+            circle( img, center, radius, color, 3, 8, 0 ); 
+        } 
+    } 
+  
+    // Show Processed Image with detected faces 
+    imshow( "Face Detection", img );  
+}