特征提取代码精选

1、特征提取代码总结颜色提取 颜色直方图提取：Code:#include #include #include using namespace std; int main( int argc, char* argv )IplImage * src= cvLoadImage(E:Downloadtest1.jpg,1); IplImage* hsv = cvCreateImage( cvGetSize(src), 8, 3 );IplImage* h_plane = cvCreateImage( cvGetSize(src), 8, 1 );IplImage* s_plane = cvCreateIm

2、age( cvGetSize(src), 8, 1 );IplImage* v_plane = cvCreateImage( cvGetSize(src), 8, 1 );IplImage* planes = h_plane, s_plane ; /* H 分量划分为16个等级，S分量划分为8个等级*/int h_bins = 16, s_bins = 8;int hist_size = h_bins, s_bins; /* H 分量的变化范围*/float h_ranges = 0, 180 ; /* S 分量的变化范围*/float s_ranges = 0, 255 ;float* ra

3、nges = h_ranges, s_ranges ; /* 输入图像转换到HSV颜色空间*/cvCvtColor( src, hsv, CV_BGR2HSV );cvCvtPixToPlane( hsv, h_plane, s_plane, v_plane, 0 ); /* 创建直方图，二维, 每个维度上均分*/CvHistogram * hist = cvCreateHist( 2, hist_size, CV_HIST_ARRAY, ranges, 1 );/* 根据H,S两个平面数据统计直方图*/cvCalcHist( planes, hist, 0, 0 ); /* 获取直方图统计的

4、最大值，用于动态显示直方图*/float max_value;cvGetMinMaxHistValue( hist, 0, &max_value, 0, 0 ); /* 设置直方图显示图像*/int height = 240;int width = (h_bins*s_bins*6);IplImage* hist_img = cvCreateImage( cvSize(width,height), 8, 3 );cvZero( hist_img ); /* 用来进行HSV到RGB颜色转换的临时单位图像*/IplImage * hsv_color = cvCreateImage(cvSize(1

5、,1),8,3);IplImage * rgb_color = cvCreateImage(cvSize(1,1),8,3);int bin_w = width / (h_bins * s_bins);for(int h = 0; h h_bins; h+)for(int s = 0; s s_bins; s+)int i = h*s_bins + s;/* 获得直方图中的统计次数，计算显示在图像中的高度*/float bin_val = cvQueryHistValue_2D( hist, h, s );int intensity = cvRound(bin_val*height/max_v

6、alue); /* 获得当前直方图代表的颜色，转换成RGB用于绘制*/cvSet2D(hsv_color,0,0,cvScalar(h*180.f / h_bins,s*255.f/s_bins,255,0);cvCvtColor(hsv_color,rgb_color,CV_HSV2BGR);CvScalar color = cvGet2D(rgb_color,0,0); cvRectangle( hist_img, cvPoint(i*bin_w,height),cvPoint(i+1)*bin_w,height - intensity),color, -1, 8, 0 ); cvName

7、dWindow( Source, 1 );cvShowImage( Source, src ); cvNamedWindow( H-S Histogram, 1 );cvShowImage( H-S Histogram, hist_img ); cvWaitKey(0);运行效果截图： 形状提取 Candy算子对边缘提取：Code： #include cv.h#include cxcore.h#include highgui.h int main( int argc, char* argv ) /声明IplImage指针 IplImage* pImg = NULL; IplImage* pCa

8、nnyImg = NULL; /载入图像，强制转化为GraypImg = cvLoadImage( E:Downloadtest.jpg, 0); /为canny边缘图像申请空间pCannyImg = cvCreateImage(cvGetSize(pImg), IPL_DEPTH_8U, 1);/canny边缘检测cvCanny(pImg, pCannyImg, 50, 150, 3); /创建窗口cvNamedWindow(src, 1);cvNamedWindow(canny,1);/显示图像cvShowImage( src, pImg ); cvShowImage( canny, pC

9、annyImg ); /等待按键cvWaitKey(0);/销毁窗口cvDestroyWindow( src ); cvDestroyWindow( canny );/释放图像cvReleaseImage( &pImg ); cvReleaseImage( &pCannyImg );return 0; 运行效果截图： 角点提取：Code： #include #include cv.h#include highgui.h#define MAX_CORNERS 100int main(void)int cornersCount=MAX_CORNERS;/得到的角点数目CvPoint2D32f co

10、rnersMAX_CORNERS;/输出角点集合IplImage *srcImage = 0,*grayImage = 0,*corners1 = 0,*corners2 = 0;int i;CvScalar color = CV_RGB(255,0,0);cvNamedWindow(image,1);/Load the image to be processedsrcImage = cvLoadImage(E:Download1.jpg,1);grayImage = cvCreateImage(cvGetSize(srcImage),IPL_DEPTH_8U,1);/copy the sou

11、rce image to copy image after converting the format/复制并转为灰度图像cvCvtColor(srcImage,grayImage,CV_BGR2GRAY);/create empty images os same size as the copied images/两幅临时位浮点图像，cvGoodFeaturesToTrack会用到corners1 = cvCreateImage(cvGetSize(srcImage),IPL_DEPTH_32F,1);corners2 = cvCreateImage(cvGetSize(srcImage),

12、IPL_DEPTH_32F,1);cvGoodFeaturesToTrack(grayImage,corners1,corners2,corners,&cornersCount,0.05,30,/角点的最小距离是0,/整个图像3,0,0.4);printf(num corners found: %dn,cornersCount);/开始画出每个点if (cornersCount0)for (i=0;icornersCount;i+)cvCircle(srcImage,cvPoint(int)(cornersi.x),(int)(cornersi.y),2,color,2,CV_AA,0);cv

13、ShowImage(image,srcImage);cvSaveImage(imagedst.png,srcImage);cvReleaseImage(&srcImage);cvReleaseImage(&grayImage);cvReleaseImage(&corners1);cvReleaseImage(&corners2);cvWaitKey(0);return 0; 运行效果截图： Hough直线提取：Code： #include #include #include int main(int argc, char* argv) IplImage* src = cvLoadImage(

14、E:Download2.jpg , 0 ); IplImage* dst; IplImage* color_dst; CvMemStorage* storage = cvCreateMemStorage(0); CvSeq* lines = 0; int i; if( !src ) return -1; dst = cvCreateImage( cvGetSize(src), 8, 1 ); color_dst = cvCreateImage( cvGetSize(src), 8, 3 ); cvCanny( src, dst, 50, 200, 3 ); cvCvtColor( dst, c

15、olor_dst, CV_GRAY2BGR );#if 0 lines = cvHoughLines2( dst, storage, CV_HOUGH_STANDARD, 1, CV_PI/180, 100, 0, 0 ); for( i = 0; i total,100); i+ ) float* line = (float*)cvGetSeqElem(lines,i); float rho = line0; float theta = line1; CvPoint pt1, pt2; double a = cos(theta), b = sin(theta); double x0 = a*

16、rho, y0 = b*rho; pt1.x = cvRound(x0 + 1000*(-b); pt1.y = cvRound(y0 + 1000*(a); pt2.x = cvRound(x0 - 1000*(-b); pt2.y = cvRound(y0 - 1000*(a); cvLine( color_dst, pt1, pt2, CV_RGB(255,0,0), 3, CV_AA, 0 ); #else lines = cvHoughLines2( dst, storage, CV_HOUGH_PROBABILISTIC, 1, CV_PI/180, 50, 50, 10 ); f

17、or( i = 0; i total; i+ ) CvPoint* line = (CvPoint*)cvGetSeqElem(lines,i); cvLine( color_dst, line0, line1, CV_RGB(255,0,0), 3, CV_AA, 0 ); #endif cvNamedWindow( Source, 1 ); cvShowImage( Source, src ); cvNamedWindow( Hough, 1 ); cvShowImage( Hough, color_dst ); cvWaitKey(0); return 0;运行效果截图： Hough圆提

18、取：Code：#include #include #include #include using namespace std;int main(int argc, char* argv) IplImage* img;img=cvLoadImage(E:Download3.jpg, 1); IplImage* gray = cvCreateImage( cvGetSize(img), 8, 1 ); CvMemStorage* storage = cvCreateMemStorage(0); cvCvtColor( img, gray, CV_BGR2GRAY ); cvSmooth( gray

19、, gray, CV_GAUSSIAN, 5, 15 );/ smooth it, otherwise a lot of false circles may be detectedCvSeq* circles = cvHoughCircles( gray, storage, CV_HOUGH_GRADIENT, 2, gray-height/4, 200, 100 ); int i; for( i = 0; i total; i+ ) float* p = (float*)cvGetSeqElem( circles, i ); cvCircle( img, cvPoint(cvRound(p0

20、),cvRound(p1), 3, CV_RGB(0,255,0), -1, 8, 0 ); cvCircle( img, cvPoint(cvRound(p0),cvRound(p1), cvRound(p2), CV_RGB(255,0,0), 3, 8, 0 ); cout圆心坐标x= cvRound(p0)endl圆心坐标y= cvRound(p1)endl; cout半径=cvRound(p2)endl; cout圆数量=totalendl; cvNamedWindow( circles, 1 ); cvShowImage( circles, img ); cvWaitKey(0);

21、 return 0;运行效果截图： Hough矩形提取：Code： #include cv.h#include highgui.h#include #include #include 载入数张包含各种形状的图片，检测出其中的正方形int thresh = 50; /阈值设为50IplImage* img = 0;IplImage* img0 = 0;CvMemStorage* storage = 0; /内存存储器是一个可用来存储诸如序列，轮廓，图形,子划分等动态增长数据结构的底层结构 CvPoint pt4;const char* wndname = Square Detection Dem

22、o; /定义四个整数坐标点angle函数用来返回（两个向量之间找到角度的余弦值）double angle( CvPoint* pt1, CvPoint* pt2, CvPoint* pt0 ) double dx1 = pt1-x - pt0-x; double dy1 = pt1-y - pt0-y; double dx2 = pt2-x - pt0-x; double dy2 = pt2-y - pt0-y; return (dx1*dx2 + dy1*dy2)/sqrt(dx1*dx1 + dy1*dy1)*(dx2*dx2 + dy2*dy2) + 1e-10); /返回图像中找到的所

23、有轮廓序列，并且序列存储在内存存储器中CvSeq* findSquares4( IplImage* img, CvMemStorage* storage ) /创建序列 CvSeq* contours;int i, c, l, N = 11; CvSize sz = cvSize( img-width & -2, img-height & -2 ); /定义矩形框大小IplImage* timg = cvCloneImage( img ); IplImage* gray = cvCreateImage( sz, 8, 1 ); IplImage* pyr = cvCreateImage( cv

24、Size(sz.width/2, sz.height/2), 8, 3 ); IplImage* tgray; CvSeq* result; /创建结果序列double s, t; 创建一个空序列用于存储轮廓角点CvSeq* squares = cvCreateSeq( 0, sizeof(CvSeq), sizeof(CvPoint), storage ); /创建序列 cvSetImageROI( timg, cvRect( 0, 0, sz.width, sz.height ); /基于给定矩形设置感兴趣区域 / down-scale and upscale the image to f

25、ilter out the noise 过滤噪音cvPyrDown( timg, pyr, 7 ); /对输入图像向下采样，timg为输入图像，pyr为输出图像，高度与宽度为输入图像一半cvPyrUp( pyr, timg, 7 ); /对输入图像向上采样，输出图像, 宽度和高度应是输入图像的2倍tgray = cvCreateImage( sz, 8, 1 ); 红绿蓝3色分别尝试提取/ find squares in every color plane of the image for( c = 0; c 3; c+ ) 提取 the c-th color plane cvSetImage

26、COI( timg, c+1 ); /设置图像感兴趣通道，选择1和2和3通道 cvCopy( timg, tgray, 0 ); /把timg（输入）赋值给tgray（输出）尝试各种阈值提取得到的（N=11） for( l = 0; l total = 4 & fabs(cvContourArea(result,CV_WHOLE_SEQ) 1000 & cvCheckContourConvexity(result) ) /当轮廓数为4，fabs为取绝对值 轮廓为凸cvContourArea计算整个轮廓的面积 s = 0; for( i = 0; i = 2 ) t = fabs(angle(

27、(CvPoint*)cvGetSeqElem( result, i ),(CvPoint*)cvGetSeqElem( result, i-2 ),(CvPoint*)cvGetSeqElem( result, i-1 ); s = s t ? s : t; if 余弦值 足够小，可以认定角度为90度直角 cos0.1=83度，能较好的趋近直角 if( s 0.3 ) for( i = 0; i h_next; cvReleaseImage( &gray ); cvReleaseImage( &pyr ); cvReleaseImage( &tgray ); cvReleaseImage( &

28、timg ); return squares; drawSquares函数用来画出在图像中找到的所有正方形轮廓/ the function draws all the squares in the imagevoid drawSquares( IplImage* img, CvSeq* squares ) CvSeqReader reader; IplImage* cpy = cvCloneImage( img ); int i; cvStartReadSeq( squares, &reader, 0 ); for( i = 0; i total; i += 4 ) CvPoint* rect

29、 = pt; int count = 4; memcpy( pt, reader.ptr, squares-elem_size ); CV_NEXT_SEQ_ELEM( squares-elem_size, reader ); memcpy( pt + 1, reader.ptr, squares-elem_size ); CV_NEXT_SEQ_ELEM( squares-elem_size, reader ); memcpy( pt + 2, reader.ptr, squares-elem_size ); CV_NEXT_SEQ_ELEM( squares-elem_size, read

30、er ); memcpy( pt + 3, reader.ptr, squares-elem_size ); CV_NEXT_SEQ_ELEM( squares-elem_size, reader ); cvPolyLine( cpy, &rect, &count, 1, 1, CV_RGB(0,255,0), 3, CV_AA, 0 ); cvShowImage( wndname, cpy ); cvReleaseImage( &cpy );void on_trackbar( int a ) if( img ) drawSquares( img, findSquares4( img, sto

31、rage ) );char* names = 1.jpg, 0 ;int main(int argc, char* argv) int i, c; storage = cvCreateMemStorage(0); for( i = 0; namesi != 0; i+ ) img0 = cvLoadImage( namesi, 1 ); if( !img0 ) printf(Couldnt load %sn, namesi ); continue; img = cvCloneImage( img0 ); cvNamedWindow( wndname, 1 ); cvCreateTrackbar

32、( canny thresh, wndname, &thresh, 1000, on_trackbar ); on_trackbar(0); c = cvWaitKey(0); cvReleaseImage( &img ); cvReleaseImage( &img0 ); cvClearMemStorage( storage ); if( c = 27 ) break; cvDestroyWindow( wndname ); return 0; 运行效果截图： 边缘直方图提取：Code： #include cv.h#include highgui.h#include #include #de

33、fine PI 3.14int main() IplImage *src = 0; / source imagre IplImage *histimg = 0; / histogram image CvHistogram *hist = 0; / define multi_demention histogram IplImage* canny; CvMat* canny_m; IplImage* dx; / the sobel x difference IplImage* dy; / the sobel y difference CvMat* gradient; / value of grad

34、ient CvMat* gradient_dir; / direction of gradient CvMat* dx_m; / format transform to matrix CvMat* dy_m; CvMat* mask; CvSize size; IplImage* gradient_im; int i,j; float theta; int hdims = 8; / 划分HIST的个数，越高越精确 float hranges_arr = -PI/2,PI/2; / 直方图的上界和下界 float* hranges = hranges_arr; float max_val; /

35、int bin_w; src=cvLoadImage(E:Downloadtest.jpg, 0); / force to gray image if(src=0) return -1; cvNamedWindow( Histogram, 0 ); /cvNamedWindow( src, 0); size=cvGetSize(src); canny=cvCreateImage(cvGetSize(src),8,1);/边缘图像 dx=cvCreateImage(cvGetSize(src),32,1);/x方向上的差分/此处的数据类型为U 不怕溢出吗？ dy=cvCreateImage(cv

36、GetSize(src),32,1); gradient_im=cvCreateImage(cvGetSize(src),32,1);/梯度图像 canny_m=cvCreateMat(size.height,size.width,CV_32FC1);/边缘矩阵 dx_m=cvCreateMat(size.height,size.width,CV_32FC1); dy_m=cvCreateMat(size.height,size.width,CV_32FC1); gradient=cvCreateMat(size.height,size.width,CV_32FC1);/梯度矩阵 gradie

37、nt_dir=cvCreateMat(size.height,size.width,CV_32FC1);/梯度方向矩阵 mask=cvCreateMat(size.height,size.width,CV_32FC1);/掩码 cvCanny(src,canny,60,180,3);/边缘检测 cvConvert(canny,canny_m);/把图像转换为矩阵 cvSobel(src,dx,1,0,3);/ 一阶X方向的图像差分:dx cvSobel(src,dy,0,1,3);/ 一阶Y方向的图像差分:dy cvConvert(dx,dx_m); cvConvert(dy,dy_m); c

38、vAdd(dx_m,dy_m,gradient); / value of gradient/梯度不是等于根号下x的导数的平方加上y导数的平方吗？ cvDiv(dx_m,dy_m,gradient_dir); / direction for(i=0;isize.height;i+) for(j=0;jbins, hist-bins, max_val ? 255. / max_val : 0., 0 ); / 缩放bin 到区间0,255 ，比例系数 cvZero( histimg ); bin_w = histimg-width /16; / hdims: 条的个数，则bin_w 为条的宽度 /

39、 画直方图 for( i = 0; i bins,i)*histimg-height/255 );/ 返回单通道数组的指定元素， 返回直方图第i条的大小，val为histimg中的i条的高度 CvScalar color = CV_RGB(255,255,0); /(hsv2rgb(i*180.f/hdims);/直方图颜色 cvRectangle( histimg, cvPoint(100+i*bin_w,histimg-height),cvPoint(100+(i+1)*bin_w,(int)(histimg-height - val), color, 1, 8, 0 ); / 画直方图画

40、矩形，左下角，右上角坐标 cvShowImage( src, src); cvShowImage( Histogram, histimg ); cvWaitKey(0); cvDestroyWindow(src); cvDestroyWindow(Histogram); cvReleaseImage( &src ); cvReleaseImage( &histimg ); cvReleaseHist ( &hist ); return 0;运行效果截图： 视频流中边缘检测：Code： #include highgui.h#include cv.h#include stdio.h#include

41、 int main(int argc,char * argv) IplImage * laplace = 0; IplImage * colorlaplace = 0; IplImage * planes3 = 0,0,0; CvCapture *capture = 0; /从摄像头读取 /*if(argc = 1 |( argc=2 & strlen(argv1)=1 & isdigit(argv10) ) capture = cvCaptureFromCAM(argc = 2 ? argv10 -0:0);*/ /从文件中读取 /* else if(argc = 2)*/ capture = cvCaptureFromAVI(1.avi); if(!capture) fprintf(stderr,Could not initialize