#include "cv.h"
#include "highgui.h"
#include <TIME.H>
#include <MATH.H>
#include <CTYPE.H>
#include <STDIO.H>
#include <STRING.H>
//#define TEST
// various tracking parameters (in seconds)
const double MHI_DURATION = 0.5;
const double MAX_TIME_DELTA = 0.5;
const double MIN_TIME_DELTA = 0.05;
const int N = 3;
//
const int CONTOUR_MAX_AERA = 16;
// ring image buffer
IplImage **buf = 0;
int last = 0;
// temporary images
IplImage *mhi = 0; // MHI: motion history image
CvFilter filter = CV_GAUSSIAN_5x5;
CvConnectedComp *cur_comp, min_comp;
CvConnectedComp comp;
CvMemStorage *storage;
CvPoint pt[4];
// 参数：
// img – 输入视频帧
// dst – 检测结果
void update_mhi( IplImage* img, IplImage* dst, int diff_threshold )
{
double timestamp = clock()/100.; // get current time in seconds
CvSize size = cvSize(img->width,img->height); // get current frame size
int i, j, idx1, idx2;
IplImage* silh;
uchar val;
float temp;
IplImage* pyr = cvCreateImage( cvSize((size.width & -2)/2, (size.height & -2)/2), 8, 1 );
CvMemStorage *stor;
CvSeq *cont, *result, *squares;
CvSeqReader reader;
if( !mhi || mhi->width != size.width || mhi->height != size.height )
{
if( buf == 0 )
{
buf = (IplImage**)malloc(N*sizeof(buf[0]));
memset( buf, 0, N*sizeof(buf[0]));
}
for( i = 0; i < N; i++ )
{
cvReleaseImage( &buf[i] );
buf[i] = cvCreateImage( size, IPL_DEPTH_8U, 1 );
cvZero( buf[i] );
}
cvReleaseImage( &mhi );
mhi = cvCreateImage( size, IPL_DEPTH_32F, 1 );
cvZero( mhi ); // clear MHI at the beginning
} // end of if(mhi)
cvCvtColor( img, buf[last], CV_BGR2GRAY ); // convert frame to grayscale
idx1 = last;
idx2 = (last + 1) % N; // index of (last - (N-1))th frame
last = idx2;
// 做帧差
silh = buf[idx2];
cvAbsDiff( buf[idx1], buf[idx2], silh ); // get difference between frames
// 对差图像做二值化
cvThreshold( silh, silh, 30, 255, CV_THRESH_BINARY ); // and threshold it
cvUpdateMotionHistory( silh, mhi, timestamp, MHI_DURATION ); // update MHI
cvCvtScale( mhi, dst, 255./MHI_DURATION,
(MHI_DURATION - timestamp)*255./MHI_DURATION );
cvCvtScale( mhi, dst, 255./MHI_DURATION, 0 );
// 中值滤波，消除小的噪声
cvSmooth( dst, dst, CV_MEDIAN, 3, 0, 0, 0 );
// 向下采样，去掉噪声
cvPyrDown( dst, pyr, 7 );
cvDilate( pyr, pyr, 0, 1 ); // 做膨胀操作，消除目标的不连续空洞
cvPyrUp( pyr, dst, 7 );
//
// 下面的程序段用来找到轮廓
//
// Create dynamic structure and sequence.
stor = cvCreateMemStorage(0);
cont = cvCreateSeq(CV_SEQ_ELTYPE_POINT, sizeof(CvSeq), sizeof(CvPoint) , stor);
// 找到所有轮廓
//cvFindContours( dst, stor, &cont, sizeof(CvContour),
// CV_RETR_LIST, CV_CHAIN_APPROX_SIMPLE, cvPoint(0,0));
cvFindContours( dst, stor, &cont, sizeof(CvContour),
CV_RETR_LIST, CV_LINK_RUNS, cvPoint(0,0));
//#ifdef TEST
// 直接使用CONTOUR中的矩形来画轮廓
for(;cont;cont = cont->h_next)
{
CvRect r = ((CvContour*)cont)->rect;
if(r.height * r.width > CONTOUR_MAX_AERA) // 面积小的方形抛弃掉
{
cvRectangle( img, cvPoint(r.x,r.y),
cvPoint(r.x + r.width, r.y + r.height),
CV_RGB(255,0,0), 1, CV_AA,0);
}
}
// free memory
cvReleaseMemStorage(&stor);
cvReleaseImage( &pyr );
//#endif
}
int main(int argc, char** argv)
{
IplImage* motion = 0;
CvCapture* capture = 0;
if( argc == 1 || (argc == 2 && strlen(argv[1]) == 1 && isdigit(argv[1][0])))
capture = cvCaptureFromCAM( argc == 2 ? argv[1][0] - '0' : 0 );
else if( argc == 2 )
capture = cvCaptureFromAVI( argv[1] );
if( capture )
{
cvNamedWindow( "Motion", 1 );
for(;;)
{
IplImage* image;
if( !cvGrabFrame( capture ))
break;
image = cvRetrieveFrame( capture );
if( image )
{
if( !motion )
{
motion = cvCreateImage( cvSize(image->width,image->height), 8, 1 );
cvZero( motion );
motion->origin = image->origin;
}
}
update_mhi( image, motion, 60 );
//cvShowImage( "Motion", image );
cvShowImage( "Motion", motion );
if( cvWaitKey(10) >= 0 )
break;
}
cvReleaseCapture( &capture );
cvDestroyWindow( "Motion" );
}
