SAD立体匹配算法在opencv中的实现

SAD算法具体原理见相关图像处理书籍。

该程序是opencv中文论坛的牛人贡献的，感谢他的工作。

 

（程序所需图片可以在网上找如http://vision.middlebury.edu/stereo/data/scenes2003/，或者问我要）

// Sum of Absolute Difference(SAD) #include <iostream> #include <stdio.h> #include <stdlib.h> #include <cv.h> #include <cxcore.h> #include <highgui.h> #include <math.h> #include <ctime> using namespace std; template<class T> class Image { private: IplImage* imgp; public: Image(IplImage* img=0){imgp=img;} ~Image(){imgp=0;} void operator=(IplImage* img){imgp=img;} inline T* operator[](const int rowIndx) { return((T*)(imgp->imageData+rowIndx*imgp->widthStep)); } }; typedef struct { unsigned char b,g,r; }RgbPixel; typedef struct { float b,g,r; }RgbPixelFloat; typedef Image<RgbPixel> RgbImage; typedef Image<RgbPixelFloat> RgbImageFloat; typedef Image<unsigned char> BwImage; typedef Image<float> BwImageFloat; //display an image in a new window with title to be given. void displayImageNewWindow(char* title,CvArr* img) { cvNamedWindow(title, CV_WINDOW_AUTOSIZE ); cvShowImage(title,img); } int getMaxMin(double value[],int valueSize, int maxmin) { int pos=0; int i=0; double max1=-1;//?-999999; double min1=999999; if (maxmin==1) { //find max for (i=0;i<valueSize;i++) { //find the index with the max value; if (value[i]>max1) { pos=i; max1=value[i]; } } } if (maxmin==0) { //find min for (i=0;i<valueSize;i++) { //find the index with the minimum value; if (value[i]<min1) { pos=i; min1=value[i]; } } } return pos; } IplImage* generateDisparityImage(IplImage* greyLeftImg32,IplImage* greyRightImg32,int windowSize,int DSR) { int offset=floor((double)windowSize/2); int height=greyLeftImg32->height; int width=greyLeftImg32->width; double* localSAD=new double[DSR]; int x=0, y=0,d=0,m=0; int N=windowSize; IplImage* winImg=cvCreateImage(cvSize(N,N),32,1);//mySubImage(greyLeftImg32,cvRect(0,0,N,N)); IplImage* disparity=cvCreateImage(cvSize(width,height),8,1);//or IPL_DEPTH_8U BwImage imgA(disparity); for (y=0;y<height;y++) { for (x=0;x<width;x++) { imgA[y][x]=0; } } CvScalar sum; //CvScalar s2; for (y=0;y<height-N;y++) { //height-N for (x=0;x<width-N;x++) { //width-N cvSetImageROI(greyLeftImg32, cvRect(x,y,N,N)); d=0; //initialise localSAD for (m=0;m<DSR;m++) { localSAD[m]=0; } //start matching do{ if (x-d>=0) { cvSetImageROI(greyRightImg32, cvRect(x-d,y,N,N)); } else { break; } cvAbsDiff(greyLeftImg32,greyRightImg32,winImg);//absolute difference sum=cvSum(winImg);//sum localSAD[d]=sum.val[0];//0 means single channel cvResetImageROI(greyRightImg32); d++; }while(d<=DSR); //to find the best d and store imgA[y+offset][x+offset]=getMaxMin(localSAD,DSR,0)*16; //0 means return minimum index cvResetImageROI(greyLeftImg32); }//x if (y%10==0) cout<<"row="<<y<<" of "<<height<<endl; }//y cvReleaseImage(&winImg); //cvReleaseImage(&rightWinImg); return disparity; } int main (int argc, char * const argv[]) { cout << "Sum of Absolute Difference(SAD) Strereo Vision"<<endl; //**********image input*********************// char* filename1="L.jpg";//im2_cone.png IplImage* greyLeftImg= cvLoadImage(filename1,0); char* filename2="R.jpg"; IplImage* greyRightImg= cvLoadImage(filename2,0); if (greyLeftImg==NULL){cout << "No valid image input."<<endl; return 1;} if (greyRightImg==NULL){cout << "No valid image input."<<endl; return 1;} int width=greyLeftImg->width; int height=greyLeftImg->height; /****************8U to 32F**********************/ IplImage* greyLeftImg32=cvCreateImage(cvSize(width,height),32,1);//IPL_DEPTH_32F IplImage* greyRightImg32=cvCreateImage(cvSize(width,height),32,1); cvConvertScale(greyLeftImg, greyLeftImg32, 1/255.); cvConvertScale(greyRightImg, greyRightImg32, 1/255.);//1/255. equals to 1/255.0 //-------------obtain disparity image---------------- time_t tstart, tend; tstart = time(0); int windowSize=13,DSR=20;//Disparity Search Range IplImage* disparity32=generateDisparityImage(greyLeftImg32,greyRightImg32,windowSize,DSR); tend = time(0); cout << "It took "<< difftime(tend, tstart) <<" second(s)."<< endl; displayImageNewWindow("Dispairty Image",disparity32); displayImageNewWindow("Left Image",greyLeftImg32); displayImageNewWindow("Right Image",greyRightImg32); //cvSaveImage("D:/OpenCV_stuff/SampleImages/disparitySAD.jpg",disparity32); //********destroy window************/ cvWaitKey(0); cvReleaseImage(&greyLeftImg32); cvReleaseImage(&greyRightImg32); cvReleaseImage(&greyLeftImg); cvReleaseImage(&greyRightImg); cvReleaseImage(&disparity32); cvDestroyWindow("Left Image"); cvDestroyWindow("Right Image"); cvDestroyWindow("Dispairty Image"); return 0; }