利用OpenCV做的摄像头互动游戏以及源代码

注：这个例子是从中国数字艺术在线上面看到的，没有做过调试，转载于此，仅仅是作为一个应用参考，供大家欣赏。原文的出处是： http://www.cgblog.com.cn/e/DoPrint/?classid=29&id=9742。

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最近看到有人用flash和摄像头做了一个互动游戏觉得很好玩，就 利用OpenCV的库函数和VC仿照也做了个类似的呵呵。效果不是很好，拿出来献丑了。下面介绍一下，电脑上连接一个摄像头，启动程序后在视频窗口中就会 有两个跳动的黄色小球作为你攻击的目标（小球搬来是要做成漂浮的泡泡的，没找到动力学方程，就随便设计了一个），还有一个白色的十字圈作为你的准星。拥有 一个红的物体在摄像头前晃动来操纵你的准星，当准星击中黄色小球的时候小球就会消失。（这个游戏需要OpenCV beta5 的动态连接库的支持。还要在当前目录下放置一副320×240的命名为gun.bmp的图，我用的就是图中的这张卡，通过它来决定你能用什么颜色的物体操 纵你的准星）


好了贴上源码看看吧

// auto.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include "cv.h"
#include "highgui.h"
#include "stdio.h"
#include "ctype.h"
#include "math.h"

IplImage *image = 0, *hsv = 0, *hue = 0, *mask = 0, *backproject = 0, *histimg = 0;
CvHistogram *hist = 0;

int backproject_mode = 0;
int select_object = 0;
int track_object = 0;
int show_hist = 1;

int Xn=0;
int Yn=0;
int Xn2=0;
int Yn2=0;

CvPoint origin;
CvPoint trackPoint;
CvRect selection;
CvRect track_window;
CvBox2D track_box;
CvConnectedComp track_comp;
int hdims = 16;
float hranges_arr[] = {0,180};
float* hranges = hranges_arr;
int vmin = 90, vmax = 256, smin = 90;

CvScalar hsv2rgb( float hue );

//加载预定图像
void loadTemplateImage()
{
IplImage *tempimage = cvLoadImage("gun.bmp",1);
cvCvtColor( tempimage, hsv, CV_BGR2HSV );
int _vmin = vmin, _vmax = vmax;

cvInRangeS( hsv, cvScalar(0,smin,MIN(_vmin,_vmax),0),
cvScalar(180,256,MAX(_vmin,_vmax),0), mask );

cvSplit( hsv, hue, 0, 0, 0 );

selection.x = 1;
selection.y = 1;
selection.width = 320-1;
selection.height= 240-1;

cvSetImageROI( hue, selection );
cvSetImageROI( mask, selection );
cvCalcHist( &hue, hist, 0, mask );

float max_val = 0.f;

cvGetMinMaxHistValue( hist, 0, &max_val, 0, 0 );
cvConvertScale( hist->bins, hist->bins, max_val ? 255. / max_val : 0., 0 );
cvResetImageROI( hue );
cvResetImageROI( mask );
track_window = selection;
track_object = 1;


cvZero( histimg );
int bin_w = histimg->width / hdims;
for(int i = 0; i < hdims; i++ )
{
int val = cvRound( cvGetReal1D(hist->bins,i)*histimg->height/255 );
CvScalar color = hsv2rgb(i*180.f/hdims);
cvRectangle( histimg, cvPoint(i*bin_w,histimg->height),
cvPoint((i+1)*bin_w,histimg->height - val),
color, -1, 8, 0 );
}

cvReleaseImage(&tempimage);

}


//鼠标事件回调函数
void on_mouse( int event, int x, int y, int flags, void* param )
{
if( !image )
return;

if( image->origin )
y = image->height - y;

if( select_object )
{
selection.x = MIN(x,origin.x);
selection.y = MIN(y,origin.y);
selection.width = selection.x + CV_IABS(x - origin.x);
selection.height = selection.y + CV_IABS(y - origin.y);

selection.x = MAX( selection.x, 0 );
selection.y = MAX( selection.y, 0 );
selection.width = MIN( selection.width, image->width );
selection.height = MIN( selection.height, image->height );
selection.width -= selection.x;
selection.height -= selection.y;
}

switch( event )
{
case CV_EVENT_LBUTTONDOWN:
origin = cvPoint(x,y);
selection = cvRect(x,y,0,0);
select_object = 1;
break;
case CV_EVENT_LBUTTONUP:
select_object = 0;
if( selection.width > 0 && selection.height > 0 )
track_object = -1;
break;
}
}


//颜色空间
CvScalar hsv2rgb( float hue )
{
int rgb[3], p, sector;
static const int sector_data[][3]=
{{0,2,1}, {1,2,0}, {1,0,2}, {2,0,1}, {2,1,0}, {0,1,2}};
hue *= 0.033333333333333333333333333333333f;
sector = cvFloor(hue);
p = cvRound(255*(hue - sector));
p ^= sector & 1 ? 255 : 0;

rgb[sector_data[sector][0]] = 255;
rgb[sector_data[sector][1]] = 0;
rgb[sector_data[sector][2]] = p;

return cvScalar(rgb[2], rgb[1], rgb[0],0);
}



//划popo
void drawCorssMark(IplImage *dst, CvPoint pt)
{

const int cross_len = 10;
CvPoint pt1,pt2,pt3,pt4;
pt1.x = pt.x;
pt1.y = pt.y - cross_len;
pt2.x = pt.x;
pt2.y = pt.y + cross_len;
pt3.x = pt.x - cross_len;
pt3.y = pt.y;
pt4.x = pt.x + cross_len;
pt4.y = pt.y;

cvCircle( dst, pt, 10, CV_RGB(255,255,255), 2,CV_AA,0);

cvLine(dst,pt1,pt2,CV_RGB(255,255,255),2,CV_AA, 0 );
cvLine(dst,pt3,pt4,CV_RGB(255,255,255),2,CV_AA, 0 );

}



//点的移动
void MovePOPO(IplImage *dst,int & Xn,int & Yn)
{

int Xn1= Xn+1;
int i=-1;
int Yn1=(int)( (Xn)+(20*sin(Xn)) );
if (Xn1 >= (dst->width))
{
Xn1=0;
Yn1=0;
} /* image width in pixels */
if (Yn1 >=(dst->height))
{
Xn1=0;
Yn1=0;
}

CvPoint pt=cvPoint(Xn1, Yn1);
cvCircle(dst, pt, 4, CV_RGB(230,255,0), 2,CV_AA,0);
Xn=Xn1;
Yn=Yn1;
}

void MovePOPO1(IplImage *dst,int & Xn,int & Yn)
{

int Xn1= Xn+2;
int Yn1=(int)( (Xn)+(10*sin(Xn)) );

if (Xn1 >= (dst->width))
{
Xn1=0;
Yn1=0;
} /* image width in pixels */
if (Yn1 >=(dst->height))
{
Xn1=0;
Yn1=0;
}

CvPoint pt=cvPoint(Xn1, Yn1);
cvCircle(dst, pt, 4, CV_RGB(230,255,0), 2,CV_AA,0);
Xn=Xn1;
Yn=Yn1;
}



int main( int argc, char** argv )
{
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 )
{
fprintf(stderr,"Could not initialize capturing...\n");
return -1;
}

printf( "Hot keys: \n"
"\tESC - quit the program\n"
"\tc - stop the tracking\n"
"\tb - switch to/from backprojection view\n"
"\th - show/hide object histogram\n"
"To initialize tracking, select the object with mouse\n" );

// cvNamedWindow( "Histogram", 0 );
cvNamedWindow( "InteractiveCAMGame", 0 );
cvSetMouseCallback( "InteractiveCAMGame", on_mouse, 0 );
// cvCreateTrackbar( "Vmin", "CamShiftDemo", &vmin, 256, 0 );
// cvCreateTrackbar( "Vmax", "CamShiftDemo", &vmax, 256, 0 );
// cvCreateTrackbar( "Smin", "CamShiftDemo", &smin, 256, 0 );

for(;;)
{
IplImage* frame = 0;
//int i, bin_w, c;
int c;

frame = cvQueryFrame( capture );
if( !frame )
break;

if( !image )
{
/* allocate all the buffers */
image = cvCreateImage( cvGetSize(frame), 8, 3 );
image->origin = frame->origin;
hsv = cvCreateImage( cvGetSize(frame), 8, 3 );
hue = cvCreateImage( cvGetSize(frame), 8, 1 );
mask = cvCreateImage( cvGetSize(frame), 8, 1 );
backproject = cvCreateImage( cvGetSize(frame), 8, 1 );
hist = cvCreateHist( 1, &hdims, CV_HIST_ARRAY, &hranges, 1 );
histimg = cvCreateImage( cvSize(320,200), 8, 3 );
cvZero( histimg );
// cvSaveImage("a.bmp",image);
loadTemplateImage();
}

cvCopy( frame, image, 0 );
cvSaveImage("a.bmp",image);
cvCvtColor( image, hsv, CV_BGR2HSV );



if( track_object )
{
int _vmin = vmin, _vmax = vmax;

cvInRangeS( hsv, cvScalar(0,smin,MIN(_vmin,_vmax),0),
cvScalar(180,256,MAX(_vmin,_vmax),0), mask );
cvSplit( hsv, hue, 0, 0, 0 );

cvCalcBackProject( &hue, backproject, hist );
cvAnd( backproject, mask, backproject, 0 );
cvCamShift( backproject, track_window,
cvTermCriteria( CV_TERMCRIT_EPS | CV_TERMCRIT_ITER, 10, 1 ),
&track_comp, &track_box );
track_window = track_comp.rect;

if( backproject_mode )
cvCvtColor( backproject, image, CV_GRAY2BGR );
if( image->origin )
track_box.angle = -track_box.angle;

// cvEllipseBox( image, track_box, CV_RGB(255,0,0), 3, CV_AA, 0 );
drawCorssMark(image, cvPointFrom32f(track_box.center));

MovePOPO(image,Xn,Yn);

MovePOPO1(image, Xn2, Yn2);
//MovePOPO(image,image->width,image->height);
trackPoint= cvPointFrom32f(track_box.center);
if ( sqrt( ((trackPoint.x-Xn)*(trackPoint.x-Xn)) + ((trackPoint.y-Yn)*(trackPoint.y-Yn)) )<10 )
{
Xn=0;
Yn=0;
MovePOPO(image,Xn,Yn);

}

}

if( select_object && selection.width > 0 && selection.height > 0 )
{
cvSetImageROI( image, selection );
cvXorS( image, cvScalarAll(255), image, 0 );
cvResetImageROI( image );
}

cvShowImage( "InteractiveCAMGame", image );
// cvShowImage( "Histogram", histimg );

c = cvWaitKey(10);
if( c == 27 )
break;
switch( c )
{
case 'b':
backproject_mode ^= 1;
break;
case 'c':
track_object = 0;
cvZero( histimg );
break;
case 'h':
show_hist ^= 1;
if( !show_hist )
cvDestroyWindow( "Histogram" );
else
cvNamedWindow( "Histogram", 1 );
break;
default:
;
}
}

cvReleaseCapture( &capture );
cvDestroyWindow("InteractiveCAMGame");

return 0;
}

#ifdef _EiC
main(1,"camshiftdemo.c");
#endif


是不是很眼熟啊，没错就是用了OpenCV那个例子