人脸检测（转）

人脸检测

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本程序可以对输入的图像或者视频进行人脸检测，运行结果如下图：

 

代码：

#include "cv.h"#include "highgui.h" #include <stdio.h>#include <stdlib.h>#include <string.h>#include <assert.h>#include <math.h>#include <float.h>#include <limits.h>#include <time.h>#include <ctype.h> #ifdef _EiC#define WIN32#endif static CvMemStorage* storage = 0;static CvHaarClassifierCascade* cascade = 0; void detect_and_draw( IplImage* image ); const char* cascade_name =    "haarcascade_frontalface_alt.xml";/*    "haarcascade_profileface.xml";*/ int main( int argc, char** argv ){    CvCapture* capture = 0;    IplImage *frame, *frame_copy = 0;    int optlen = strlen("--cascade=");    const char* input_name;     if( argc > 1 && strncmp( argv[1], "--cascade=", optlen ) == 0 )    {        cascade_name = argv[1] + optlen;        input_name = argc > 2 ? argv[2] : 0;    }    else    {        cascade_name = "../../data/haarcascades/haarcascade_frontalface_alt2.xml";        //opencv装好后haarcascade_frontalface_alt2.xml的路径,       //也可以把这个文件拷到你的工程文件夹下然后不用写路径名cascade_name= "haarcascade_frontalface_alt2.xml";         //或者cascade_name ="C://Program Files//OpenCV//data//haarcascades//haarcascade_frontalface_alt2.xml"        input_name = argc > 1 ? argv[1] : 0;    }     cascade = (CvHaarClassifierCascade*)cvLoad( cascade_name, 0, 0, 0 );     if( !cascade )    {        fprintf( stderr, "ERROR: Could not load classifier cascade/n" );        fprintf( stderr,        "Usage: facedetect --cascade=/"<cascade_path>/" [filename|camera_index]/n" );        return -1;    }    storage = cvCreateMemStorage(0);     if( !input_name || (isdigit(input_name[0]) && input_name[1] == '/0') )        capture = cvCaptureFromCAM( !input_name ? 0 : input_name[0] - '0' );    else        capture = cvCaptureFromAVI( input_name );      cvNamedWindow( "result", 1 );     if( capture )    {        for(;;)        {            if( !cvGrabFrame( capture ))                break;            frame = cvRetrieveFrame( capture );            if( !frame )                break;            if( !frame_copy )                frame_copy = cvCreateImage( cvSize(frame->width,frame->height),                                            IPL_DEPTH_8U, frame->nChannels );            if( frame->origin == IPL_ORIGIN_TL )                cvCopy( frame, frame_copy, 0 );            else                cvFlip( frame, frame_copy, 0 );             detect_and_draw( frame_copy );             if( cvWaitKey( 10 ) >= 0 )                break;        }         cvReleaseImage( &frame_copy );        cvReleaseCapture( &capture );    }    else    {        const char* filename = input_name ? input_name : (char*)"lena.jpg";        IplImage* image = cvLoadImage( filename, 1 );         if( image )        {            detect_and_draw( image );            cvWaitKey(0);            cvReleaseImage( &image );        }        else        {            /* assume it is a text file containing the               list of the image filenames to be processed - one per line */            FILE* f = fopen( filename, "rt" );            if( f )            {                char buf[1000+1];                while( fgets( buf, 1000, f ) )                {                    int len = (int)strlen(buf);                    while( len > 0 && isspace(buf[len-1]) )                        len--;                    buf[len] = '/0';                    image = cvLoadImage( buf, 1 );                    if( image )                    {                        detect_and_draw( image );                        cvWaitKey(0);                        cvReleaseImage( &image );                    }                }                fclose(f);            }        }     }     cvDestroyWindow("result");     return 0;} void detect_and_draw( IplImage* img ){    static CvScalar colors[] =     {        {{0,0,255}},        {{0,128,255}},        {{0,255,255}},        {{0,255,0}},        {{255,128,0}},        {{255,255,0}},        {{255,0,0}},        {{255,0,255}}    };     double scale = 1.3;    IplImage* gray = cvCreateImage( cvSize(img->width,img->height), 8, 1 );    IplImage* small_img = cvCreateImage( cvSize( cvRound (img->width/scale),                         cvRound (img->height/scale)),                     8, 1 );    int i;     cvCvtColor( img, gray, CV_BGR2GRAY );    cvResize( gray, small_img, CV_INTER_LINEAR );    cvEqualizeHist( small_img, small_img );    cvClearMemStorage( storage );     if( cascade )    {        double t = (double)cvGetTickCount();        CvSeq* faces = cvHaarDetectObjects( small_img, cascade, storage,                                            1.1, 2, 0/*CV_HAAR_DO_CANNY_PRUNING*/,                                            cvSize(30, 30) );        t = (double)cvGetTickCount() - t;        printf( "detection time = %gms/n", t/((double)cvGetTickFrequency()*1000.) );        for( i = 0; i < (faces ? faces->total : 0); i++ )        {            CvRect* r = (CvRect*)cvGetSeqElem( faces, i );            CvPoint center;            int radius;            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);            cvCircle( img, center, radius, colors[i%8], 3, 8, 0 );        }    }     cvShowImage( "result", img );    cvReleaseImage( &gray );    cvReleaseImage( &small_img );}