Update face detection samples

samples/cpp/facedetect.cpp

 #include "opencv2/objdetect.hpp"
-#include "opencv2/imgcodecs.hpp"
-#include "opencv2/videoio.hpp"
 #include "opencv2/highgui.hpp"
 #include "opencv2/imgproc.hpp"
-#include "opencv2/core/utility.hpp"
-
-#include "opencv2/videoio/videoio_c.h"
-#include "opencv2/highgui/highgui_c.h"
-
-#include <cctype>
 #include <iostream>
-#include <iterator>
-#include <stdio.h>
 
 using namespace std;
 using namespace cv;
@@ -28,7 +18,7 @@ static void help()
                "   [--try-flip]\n"
                "   [filename|camera_index]\n\n"
             "see facedetect.cmd for one call:\n"
-            "./facedetect --cascade=\"../../data/haarcascades/haarcascade_frontalface_alt.xml\" --nested-cascade=\"../../data/haarcascades/haarcascade_eye.xml\" --scale=1.3\n\n"
+            "./facedetect --cascade=\"../../data/haarcascades/haarcascade_frontalface_alt.xml\" --nested-cascade=\"../../data/haarcascades/haarcascade_eye_tree_eyeglasses.xml\" --scale=1.3\n\n"
             "During execution:\n\tHit any key to quit.\n"
             "\tUsing OpenCV version " << CV_VERSION << "\n" << endl;
 }
@@ -42,8 +32,8 @@ string nestedCascadeName = "../../data/haarcascades/haarcascade_eye_tree_eyeglas
 
 int main( int argc, const char** argv )
 {
-    CvCapture* capture = 0;
-    Mat frame, frameCopy, image;
+    VideoCapture capture;
+    Mat frame, image;
     const string scaleOpt = "--scale=";
     size_t scaleOptLen = scaleOpt.length();
     const string cascadeOpt = "--cascade=";
@@ -103,17 +93,17 @@ int main( int argc, const char** argv )
 
     if( inputName.empty() || (isdigit(inputName.c_str()[0]) && inputName.c_str()[1] == '\0') )
     {
-        capture = cvCaptureFromCAM( inputName.empty() ? 0 : inputName.c_str()[0] - '0' );
         int c = inputName.empty() ? 0 : inputName.c_str()[0] - '0' ;
-        if(!capture) cout << "Capture from CAM " <<  c << " didn't work" << endl;
+        if(!capture.open(c))
+            cout << "Capture from camera #" <<  c << " didn't work" << endl;
     }
     else if( inputName.size() )
     {
         image = imread( inputName, 1 );
         if( image.empty() )
         {
-            capture = cvCaptureFromAVI( inputName.c_str() );
-            if(!capture) cout << "Capture from AVI didn't work" << endl;
+            if(!capture.open( inputName ))
+                cout << "Could not read " << inputName << endl;
         }
     }
     else
@@ -122,36 +112,27 @@ int main( int argc, const char** argv )
         if(image.empty()) cout << "Couldn't read ../data/lena.jpg" << endl;
     }
 
-    cvNamedWindow( "result", 1 );
-
-    if( capture )
+    if( capture.isOpened() )
     {
-        cout << "In capture ..." << endl;
+        cout << "Video capturing has been started ..." << endl;
+
         for(;;)
         {
-            IplImage* iplImg = cvQueryFrame( capture );
-            frame = cv::cvarrToMat(iplImg);
+            capture >> frame;
             if( frame.empty() )
                 break;
-            if( iplImg->origin == IPL_ORIGIN_TL )
-                frame.copyTo( frameCopy );
-            else
-                flip( frame, frameCopy, 0 );
 
-            detectAndDraw( frameCopy, cascade, nestedCascade, scale, tryflip );
+            Mat frame1 = frame.clone();
+            detectAndDraw( frame1, cascade, nestedCascade, scale, tryflip );
 
-            if( waitKey( 10 ) >= 0 )
-                goto _cleanup_;
+            int c = waitKey(10);
+            if( c == 27 || c == 'q' || c == 'Q' )
+                break;
         }
-
-        waitKey(0);
-
-_cleanup_:
-        cvReleaseCapture( &capture );
     }
     else
     {
-        cout << "In image read" << endl;
+        cout << "Detecting face(s) in " << inputName << endl;
         if( !image.empty() )
         {
             detectAndDraw( image, cascade, nestedCascade, scale, tryflip );
@@ -190,8 +171,6 @@ _cleanup_:
         }
     }
 
-    cvDestroyWindow("result");
-
     return 0;
 }
 
@@ -199,21 +178,24 @@ void detectAndDraw( Mat& img, CascadeClassifier& cascade,
                     CascadeClassifier& nestedCascade,
                     double scale, bool tryflip )
 {
-    int i = 0;
     double t = 0;
     vector<Rect> faces, faces2;
-    const static Scalar colors[] =  { CV_RGB(0,0,255),
-        CV_RGB(0,128,255),
-        CV_RGB(0,255,255),
-        CV_RGB(0,255,0),
-        CV_RGB(255,128,0),
-        CV_RGB(255,255,0),
-        CV_RGB(255,0,0),
-        CV_RGB(255,0,255)} ;
-    Mat gray, smallImg( cvRound (img.rows/scale), cvRound(img.cols/scale), CV_8UC1 );
+    const static Scalar colors[] =
+    {
+        Scalar(255,0,0),
+        Scalar(255,128,0),
+        Scalar(255,255,0),
+        Scalar(0,255,0),
+        Scalar(0,128,255),
+        Scalar(0,255,255),
+        Scalar(0,0,255),
+        Scalar(255,0,255)
+    };
+    Mat gray, smallImg;
 
     cvtColor( img, gray, COLOR_BGR2GRAY );
-    resize( gray, smallImg, smallImg.size(), 0, 0, INTER_LINEAR );
+    double fx = 1 / scale;
+    resize( gray, smallImg, Size(), fx, fx, INTER_LINEAR );
     equalizeHist( smallImg, smallImg );
 
     t = (double)cvGetTickCount();
@@ -221,8 +203,7 @@ void detectAndDraw( Mat& img, CascadeClassifier& cascade,
         1.1, 2, 0
         //|CASCADE_FIND_BIGGEST_OBJECT
         //|CASCADE_DO_ROUGH_SEARCH
-        |CASCADE_SCALE_IMAGE
-        ,
+        |CASCADE_SCALE_IMAGE,
         Size(30, 30) );
     if( tryflip )
     {
@@ -231,8 +212,7 @@ void detectAndDraw( Mat& img, CascadeClassifier& cascade,
                                  1.1, 2, 0
                                  //|CASCADE_FIND_BIGGEST_OBJECT
                                  //|CASCADE_DO_ROUGH_SEARCH
-                                 |CASCADE_SCALE_IMAGE
-                                 ,
+                                 |CASCADE_SCALE_IMAGE,
                                  Size(30, 30) );
         for( vector<Rect>::const_iterator r = faces2.begin(); r != faces2.end(); r++ )
         {
@@ -241,44 +221,45 @@ void detectAndDraw( Mat& img, CascadeClassifier& cascade,
     }
     t = (double)cvGetTickCount() - t;
     printf( "detection time = %g ms\n", t/((double)cvGetTickFrequency()*1000.) );
-    for( vector<Rect>::const_iterator r = faces.begin(); r != faces.end(); r++, i++ )
+    for ( size_t i = 0; i < faces.size(); i++ )
     {
+        Rect r = faces[i];
         Mat smallImgROI;
         vector<Rect> nestedObjects;
         Point center;
         Scalar color = colors[i%8];
         int radius;
 
-        double aspect_ratio = (double)r->width/r->height;
+        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);
+            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)),
+            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);
+        smallImgROI = smallImg( r );
         nestedCascade.detectMultiScale( smallImgROI, nestedObjects,
             1.1, 2, 0
             //|CASCADE_FIND_BIGGEST_OBJECT
             //|CASCADE_DO_ROUGH_SEARCH
             //|CASCADE_DO_CANNY_PRUNING
-            |CASCADE_SCALE_IMAGE
-            ,
+            |CASCADE_SCALE_IMAGE,
             Size(30, 30) );
-        for( vector<Rect>::const_iterator nr = nestedObjects.begin(); nr != nestedObjects.end(); nr++ )
+        for ( size_t j = 0; j < nestedObjects.size(); 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);
+            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 );
         }
     }
-    cv::imshow( "result", img );
+    imshow( "result", img );
 }

samples/cpp/smiledetect.cpp

 #include "opencv2/objdetect.hpp"
 #include "opencv2/highgui.hpp"
 #include "opencv2/imgproc.hpp"
-#include "opencv2/core/utility.hpp"
-
-#include "opencv2/videoio/videoio_c.h"
-#include "opencv2/highgui/highgui_c.h"
-
-#include <cctype>
 #include <iostream>
-#include <iterator>
-#include <stdio.h>
 
 using namespace std;
 using namespace cv;
@@ -36,11 +28,10 @@ void detectAndDraw( Mat& img, CascadeClassifier& cascade,
 string cascadeName = "../../data/haarcascades/haarcascade_frontalface_alt.xml";
 string nestedCascadeName = "../../data/haarcascades/haarcascade_smile.xml";
 
-
 int main( int argc, const char** argv )
 {
-    CvCapture* capture = 0;
-    Mat frame, frameCopy, image;
+    VideoCapture capture;
+    Mat frame, image;
     const string scaleOpt = "--scale=";
     size_t scaleOptLen = scaleOpt.length();
     const string cascadeOpt = "--cascade=";
@@ -104,44 +95,34 @@ int main( int argc, const char** argv )
 
     if( inputName.empty() || (isdigit(inputName.c_str()[0]) && inputName.c_str()[1] == '\0') )
     {
-        capture = cvCaptureFromCAM( inputName.empty() ? 0 : inputName.c_str()[0] - '0' );
         int c = inputName.empty() ? 0 : inputName.c_str()[0] - '0' ;
-        if(!capture) cout << "Capture from CAM " <<  c << " didn't work" << endl;
+        if(!capture.open(c))
+            cout << "Capture from camera #" <<  c << " didn't work" << endl;
     }
     else if( inputName.size() )
     {
-        capture = cvCaptureFromAVI( inputName.c_str() );
-        if(!capture) cout << "Capture from AVI didn't work" << endl;
+        if(!capture.open( inputName ))
+            cout << "Could not read " << inputName << endl;
     }
 
-    cvNamedWindow( "result", 1 );
-
-    if( capture )
+    if( capture.isOpened() )
     {
-        cout << "In capture ..." << endl;
+        cout << "Video capturing has been started ..." << endl;
         cout << endl << "NOTE: Smile intensity will only be valid after a first smile has been detected" << endl;
 
         for(;;)
         {
-            IplImage* iplImg = cvQueryFrame( capture );
-            frame = cv::cvarrToMat(iplImg);
+            capture >> frame;
             if( frame.empty() )
                 break;
-            if( iplImg->origin == IPL_ORIGIN_TL )
-                frame.copyTo( frameCopy );
-            else
-                flip( frame, frameCopy, 0 );
 
-            detectAndDraw( frameCopy, cascade, nestedCascade, scale, tryflip );
+            Mat frame1 = frame.clone();
+            detectAndDraw( frame1, cascade, nestedCascade, scale, tryflip );
 
-            if( waitKey( 10 ) >= 0 )
-                goto _cleanup_;
+            int c = waitKey(10);
+            if( c == 27 || c == 'q' || c == 'Q' )
+                break;
         }
-
-        waitKey(0);
-
-_cleanup_:
-        cvReleaseCapture( &capture );
     }
     else
     {
@@ -150,7 +131,6 @@ _cleanup_:
         return -1;
     }
 
-    cvDestroyWindow("result");
     return 0;
 }
 
@@ -158,28 +138,31 @@ void detectAndDraw( Mat& img, CascadeClassifier& cascade,
                     CascadeClassifier& nestedCascade,
                     double scale, bool tryflip)
 {
-    int i = 0;
     vector<Rect> faces, faces2;
-    const static Scalar colors[] =  { CV_RGB(0,0,255),
-        CV_RGB(0,128,255),
-        CV_RGB(0,255,255),
-        CV_RGB(0,255,0),
-        CV_RGB(255,128,0),
-        CV_RGB(255,255,0),
-        CV_RGB(255,0,0),
-        CV_RGB(255,0,255)} ;
-    Mat gray, smallImg( cvRound (img.rows/scale), cvRound(img.cols/scale), CV_8UC1 );
+    const static Scalar colors[] =
+    {
+        Scalar(255,0,0),
+        Scalar(255,128,0),
+        Scalar(255,255,0),
+        Scalar(0,255,0),
+        Scalar(0,128,255),
+        Scalar(0,255,255),
+        Scalar(0,0,255),
+        Scalar(255,0,255)
+    };
+    Mat gray, smallImg;
 
     cvtColor( img, gray, COLOR_BGR2GRAY );
-    resize( gray, smallImg, smallImg.size(), 0, 0, INTER_LINEAR );
+
+    double fx = 1 / scale;
+    resize( gray, smallImg, Size(), fx, fx, INTER_LINEAR );
     equalizeHist( smallImg, smallImg );
 
     cascade.detectMultiScale( smallImg, faces,
         1.1, 2, 0
         //|CASCADE_FIND_BIGGEST_OBJECT
         //|CASCADE_DO_ROUGH_SEARCH
-        |CASCADE_SCALE_IMAGE
-        ,
+        |CASCADE_SCALE_IMAGE,
         Size(30, 30) );
     if( tryflip )
     {
@@ -188,8 +171,7 @@ void detectAndDraw( Mat& img, CascadeClassifier& cascade,
                                  1.1, 2, 0
                                  //|CASCADE_FIND_BIGGEST_OBJECT
                                  //|CASCADE_DO_ROUGH_SEARCH
-                                 |CASCADE_SCALE_IMAGE
-                                 ,
+                                 |CASCADE_SCALE_IMAGE,
                                  Size(30, 30) );
         for( vector<Rect>::const_iterator r = faces2.begin(); r != faces2.end(); r++ )
         {
@@ -197,38 +179,38 @@ void detectAndDraw( Mat& img, CascadeClassifier& cascade,
         }
     }
 
-    for( vector<Rect>::iterator r = faces.begin(); r != faces.end(); r++, i++ )
+    for ( size_t i = 0; i < faces.size(); i++ )
     {
+        Rect r = faces[i];
         Mat smallImgROI;
         vector<Rect> nestedObjects;
         Point center;
         Scalar color = colors[i%8];
         int radius;
 
-        double aspect_ratio = (double)r->width/r->height;
+        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);
+            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)),
+            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);
 
-        const int half_height=cvRound((float)r->height/2);
-        r->y=r->y + half_height;
-        r->height = half_height;
-        smallImgROI = smallImg(*r);
+        const int half_height=cvRound((float)r.height/2);
+        r.y=r.y + half_height;
+        r.height = half_height-1;
+        smallImgROI = smallImg( r );
         nestedCascade.detectMultiScale( smallImgROI, nestedObjects,
             1.1, 0, 0
             //|CASCADE_FIND_BIGGEST_OBJECT
             //|CASCADE_DO_ROUGH_SEARCH
             //|CASCADE_DO_CANNY_PRUNING
-            |CASCADE_SCALE_IMAGE
-            ,
+            |CASCADE_SCALE_IMAGE,
             Size(30, 30) );
 
         // The number of detected neighbors depends on image size (and also illumination, etc.). The
@@ -243,9 +225,9 @@ void detectAndDraw( Mat& img, CascadeClassifier& cascade,
         // Draw rectangle on the left side of the image reflecting smile intensity
         float intensityZeroOne = ((float)smile_neighbors - min_neighbors) / (max_neighbors - min_neighbors + 1);
         int rect_height = cvRound((float)img.rows * intensityZeroOne);
-        CvScalar col = CV_RGB((float)255 * intensityZeroOne, 0, 0);
+        Scalar col = Scalar((float)255 * intensityZeroOne, 0, 0);
         rectangle(img, cvPoint(0, img.rows), cvPoint(img.cols/10, img.rows - rect_height), col, -1);
     }
 
-    cv::imshow( "result", img );
+    imshow( "result", img );
 }

samples/cpp/ufacedetect.cpp → samples/tapi/ufacedetect.cpp

 #include "opencv2/objdetect.hpp"
-#include "opencv2/imgcodecs.hpp"
-#include "opencv2/videoio.hpp"
 #include "opencv2/highgui.hpp"
 #include "opencv2/imgproc.hpp"
-#include "opencv2/core/utility.hpp"
 #include "opencv2/core/ocl.hpp"
-
-#include <cctype>
 #include <iostream>
-#include <iterator>
-#include <stdio.h>
 
 using namespace std;
 using namespace cv;
@@ -20,13 +13,13 @@ static void help()
             "This classifier can recognize many kinds of rigid objects, once the appropriate classifier is trained.\n"
             "It's most known use is for faces.\n"
             "Usage:\n"
-            "./facedetect [--cascade=<cascade_path> this is the primary trained classifier such as frontal face]\n"
+            "./ufacedetect [--cascade=<cascade_path> this is the primary trained classifier such as frontal face]\n"
                "   [--nested-cascade[=nested_cascade_path this an optional secondary classifier such as eyes]]\n"
                "   [--scale=<image scale greater or equal to 1, try 1.3 for example>]\n"
                "   [--try-flip]\n"
                "   [filename|camera_index]\n\n"
             "see facedetect.cmd for one call:\n"
-            "./facedetect --cascade=\"../../data/haarcascades/haarcascade_frontalface_alt.xml\" --nested-cascade=\"../../data/haarcascades/haarcascade_eye.xml\" --scale=1.3\n\n"
+            "./ufacedetect --cascade=\"../../data/haarcascades/haarcascade_frontalface_alt.xml\" --nested-cascade=\"../../data/haarcascades/haarcascade_eye_tree_eyeglasses.xml\" --scale=1.3\n\n"
             "During execution:\n\tHit any key to quit.\n"
             "\tUsing OpenCV version " << CV_VERSION << "\n" << endl;
 }
@@ -76,7 +69,7 @@ int main( int argc, const char** argv )
         }
         else if( scaleOpt.compare( 0, scaleOptLen, argv[i], scaleOptLen ) == 0 )
         {
-            if( !sscanf( argv[i] + scaleOpt.length(), "%lf", &scale ) || scale > 1 )
+            if( !sscanf( argv[i] + scaleOpt.length(), "%lf", &scale ) )
                 scale = 1;
             cout << " from which we read scale = " << scale << endl;
         }
@@ -87,7 +80,7 @@ int main( int argc, const char** argv )
         }
         else if( argv[i][0] == '-' )
         {
-            cerr << "WARNING: Unknown option %s" << argv[i] << endl;
+            cerr << "WARNING: Unknown option " << argv[i] << endl;
         }
         else
             inputName = argv[i];
@@ -120,8 +113,6 @@ int main( int argc, const char** argv )
         }
     }
 
-    namedWindow( "result", 1 );
-
     if( capture.isOpened() )
     {
         cout << "Video capturing has been started ..." << endl;
@@ -133,7 +124,8 @@ int main( int argc, const char** argv )
 
             detectAndDraw( frame, canvas, cascade, nestedCascade, scale, tryflip );
 
-            if( waitKey( 10 ) >= 0 )
+            int c = waitKey(10);
+            if( c == 27 || c == 'q' || c == 'Q' )
                 break;
         }
     }
@@ -183,46 +175,44 @@ int main( int argc, const char** argv )
 
 void detectAndDraw( UMat& img, Mat& canvas, CascadeClassifier& cascade,
                     CascadeClassifier& nestedCascade,
-                    double scale0, bool tryflip )
+                    double scale, bool tryflip )
 {
-    int i = 0;
-    double t = 0, scale=1;
+    double t = 0;
     vector<Rect> faces, faces2;
     const static Scalar colors[] =
     {
-        Scalar(0,0,255),
-        Scalar(0,128,255),
-        Scalar(0,255,255),
-        Scalar(0,255,0),
+        Scalar(255,0,0),
         Scalar(255,128,0),
         Scalar(255,255,0),
-        Scalar(255,0,0),
+        Scalar(0,255,0),
+        Scalar(0,128,255),
+        Scalar(0,255,255),
+        Scalar(0,0,255),
         Scalar(255,0,255)
     };
     static UMat gray, smallImg;
 
     t = (double)getTickCount();
 
-    resize( img, smallImg, Size(), scale0, scale0, INTER_LINEAR );
-    cvtColor( smallImg, gray, COLOR_BGR2GRAY );
-    equalizeHist( gray, gray );
+    cvtColor( img, gray, COLOR_BGR2GRAY );
+    double fx = 1 / scale;
+    resize( gray, smallImg, Size(), fx, fx, INTER_LINEAR );
+    equalizeHist( smallImg, smallImg );
 
-    cascade.detectMultiScale( gray, faces,
+    cascade.detectMultiScale( smallImg, faces,
         1.1, 3, 0
         //|CASCADE_FIND_BIGGEST_OBJECT
         //|CASCADE_DO_ROUGH_SEARCH
-        |CASCADE_SCALE_IMAGE
-        ,
+        |CASCADE_SCALE_IMAGE,
         Size(30, 30) );
     if( tryflip )
     {
-        flip(gray, gray, 1);
-        cascade.detectMultiScale( gray, faces2,
+        flip(smallImg, smallImg, 1);
+        cascade.detectMultiScale( smallImg, faces2,
                                  1.1, 2, 0
                                  //|CASCADE_FIND_BIGGEST_OBJECT
                                  //|CASCADE_DO_ROUGH_SEARCH
-                                 |CASCADE_SCALE_IMAGE
-                                 ,
+                                 |CASCADE_SCALE_IMAGE,
                                  Size(30, 30) );
         for( vector<Rect>::const_iterator r = faces2.begin(); r != faces2.end(); r++ )
         {
@@ -230,7 +220,7 @@ void detectAndDraw( UMat& img, Mat& canvas, CascadeClassifier& cascade,
         }
     }
     t = (double)getTickCount() - t;
-    smallImg.copyTo(canvas);
+    img.copyTo(canvas);
 
     double fps = getTickFrequency()/t;
     static double avgfps = 0;
@@ -242,41 +232,43 @@ void detectAndDraw( UMat& img, Mat& canvas, CascadeClassifier& cascade,
     putText(canvas, format("OpenCL: %s, fps: %.1f", ocl::useOpenCL() ? "ON" : "OFF", avgfps), Point(50, 30),
             FONT_HERSHEY_SIMPLEX, 0.8, Scalar(0,255,0), 2);
 
-    for( vector<Rect>::const_iterator r = faces.begin(); r != faces.end(); r++, i++ )
+    for ( size_t i = 0; i < faces.size(); i++ )
     {
+        Rect r = faces[i];
         vector<Rect> nestedObjects;
         Point center;
         Scalar color = colors[i%8];
         int radius;
 
-        double aspect_ratio = (double)r->width/r->height;
+        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);
+            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( canvas, center, radius, color, 3, 8, 0 );
         }
         else
-            rectangle( canvas, Point(cvRound(r->x*scale), cvRound(r->y*scale)),
-                       Point(cvRound((r->x + r->width-1)*scale), cvRound((r->y + r->height-1)*scale)),
+            rectangle( canvas, Point(cvRound(r.x*scale), cvRound(r.y*scale)),
+                       Point(cvRound((r.x + r.width-1)*scale), cvRound((r.y + r.height-1)*scale)),
                        color, 3, 8, 0);
         if( nestedCascade.empty() )
             continue;
-        UMat smallImgROI = gray(*r);
+        UMat smallImgROI = smallImg(r);
         nestedCascade.detectMultiScale( smallImgROI, nestedObjects,
             1.1, 2, 0
             //|CASCADE_FIND_BIGGEST_OBJECT
             //|CASCADE_DO_ROUGH_SEARCH
             //|CASCADE_DO_CANNY_PRUNING
-            |CASCADE_SCALE_IMAGE
-            ,
+            |CASCADE_SCALE_IMAGE,
             Size(30, 30) );
-        for( vector<Rect>::const_iterator nr = nestedObjects.begin(); nr != nestedObjects.end(); nr++ )
+
+        for ( size_t j = 0; j < nestedObjects.size(); 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);
+            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( canvas, center, radius, color, 3, 8, 0 );
         }
     }