Learning opencv中的一个基于级联的Hear分类器的人脸检测

检测效果图：

如果是很多人的话，检测的就不是特别好，会漏检，误检

稍微修改注释后的源代码：

#include "stdafx.h"
#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>
static CvMemStorage* storage = 0;
static CvHaarClassifierCascade* cascade = 0;
static CvHaarClassifierCascade* nested_cascade = 0;
int    use_nested_cascade = 0;
void detect_and_draw( IplImage* image );
const char* cascade_name =
"haarcascade_frontalface_alt.xml";
const char* nested_cascade_name =
"haarcascade_eye_tree_eyeglasses.xml";
double scale = 1;
int main( int argc, char** argv )
{
CvCapture* capture = 0;
IplImage *frame, *frame_copy = 0;
IplImage *image = 0;
const char* scale_opt = "--scale=";
int scale_opt_len = (int)strlen(scale_opt);
const char* cascade_opt = "--cascade=";
int cascade_opt_len = (int)strlen(cascade_opt);
const char* nested_cascade_opt = "--nested-cascade";
int nested_cascade_opt_len = (int)strlen(nested_cascade_opt);
int i;
const char* input_name = 0;
/*  for( i = 1; i < argc; i++ )
{
if( strncmp( argv[i], cascade_opt, cascade_opt_len) == 0 )
cascade_name = argv[i] + cascade_opt_len;
else if( strncmp( argv[i], nested_cascade_opt, nested_cascade_opt_len ) == 0 )
{
if( argv[i][nested_cascade_opt_len] == '=' )
nested_cascade_name = argv[i] + nested_cascade_opt_len + 1;
nested_cascade = (CvHaarClassifierCascade*)cvLoad( nested_cascade_name, 0, 0, 0 );
if( !nested_cascade )
fprintf( stderr, "WARNING: Could not load classifier cascade for nested objects\n" );
}
else if( strncmp( argv[i], scale_opt, scale_opt_len ) == 0 )
{
if( !sscanf( argv[i] + scale_opt_len, "%lf", &scale ) || scale < 1 )
scale = 1;
}
else if( argv[i][0] == '-' )
{
fprintf( stderr, "WARNING: Unknown option %s\n", argv[i] );
}
else
input_name = argv[i];
}*/
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>\"]\n"
"   [--nested-cascade[=\"nested_cascade_path\"]]\n"
"   [--scale[=<image scale>\n"
"   [filename|camera_index]\n" );
return -1;
}
storage = cvCreateMemStorage(0);
image = cvLoadImage( "lena.jpg", 1 );
cvNamedWindow( "result", 1 );
{
if( image )
{
detect_and_draw( image );
cvSaveImage("1.jpg" , image);
cvWaitKey(0);
cvReleaseImage( &image );
}
}
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}}
};
IplImage *gray, *small_img;
int i, j;
gray = cvCreateImage( cvSize(img->width,img->height), 8, 1 );
small_img = cvCreateImage( cvSize( cvRound (img->width/scale),
cvRound (img->height/scale)), 8, 1 );
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();//返回时钟计数
CvSeq* faces = cvHaarDetectObjects( small_img, cascade, storage,
1.1, 2, 0
//|CV_HAAR_FIND_BIGGEST_OBJECT
//|CV_HAAR_DO_ROUGH_SEARCH
|CV_HAAR_DO_CANNY_PRUNING
//|CV_HAAR_SCALE_IMAGE
,
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 );
CvMat small_img_roi;
CvSeq* nested_objects;
CvPoint center;
CvScalar color = colors[i%8];
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, color, 3, 8, 0 );
if( !nested_cascade )
continue;
cvGetSubRect( small_img, &small_img_roi, *r );
nested_objects = cvHaarDetectObjects( &small_img_roi, nested_cascade, storage,
1.1, 2, 0
//|CV_HAAR_FIND_BIGGEST_OBJECT
//|CV_HAAR_DO_ROUGH_SEARCH
//|CV_HAAR_DO_CANNY_PRUNING
//|CV_HAAR_SCALE_IMAGE
,
cvSize(0, 0) );
for( j = 0; j < (nested_objects ? nested_objects->total : 0); j++ )
{
CvRect* nr = (CvRect*)cvGetSeqElem( nested_objects, 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);
cvCircle( img, center, radius, color, 3, 8, 0 );
}
}
}
cvShowImage( "result", img );
cvReleaseImage( &gray );
cvReleaseImage( &small_img );
}