#include?“cv.h“
#include?
#include?“highgui.h“
#include?
#include?
#include?
#include?
#include?
//?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
int?filter?=?CV_GAUSSIAN_5x5;
CvConnectedComp?*cur_comp?min_comp;
CvConnectedComp?comp;
CvMemStorage?*storage;?CvPoint?pt[4];
//?參數(shù)：
//?img?–?輸入視頻幀
//?dst?–?檢測(cè)結(jié)果
void?update_mhi（?IplImage*?img?IplImage*?dst?int?diff_threshold?）
{??????
	double?timestamp?=?clock（）/100.;?
	//?get?current?time?in?seconds????
	CvSize?size?=?cvSize（img->widthimg->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?		{
			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;
	?//?做幀差
	?silh?=?buf[idx2];
	?cvAbsDiff（?buf[idx1]?buf[idx2]?silh?）;
	?//?get?difference?between?frames
	?//?對(duì)差圖像做二值化
	?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