C语言实现Harris角点检测与OpenCV源码解析

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
#define B(image,x,y) ((uchar *)(image->imageData+image->widthStep*(y)))[(x)*3]
#define G(image,x,y) ((uchar *)(image->imageData+image->widthStep*(y)))[(x)*3+1]
#define R(image,x,y) ((uchar *)(image->imageData+image->widthStep*(y)))[(x)*3+2]
#define S(image,x,y) ((uchar *)(image->imageData+image->widthStep*(y)))[(x)]

//卷积计算求Ix,Iy,以及滤波
//a指向的数组是size1*size2大小的...求导
CvMat *mbys(CvMat *mat,int xwidth,int ywidth,double *a,int size1,int size2)
{
    int i,j;
    int i1,j1;
    int px,py;
    int m;
    CvMat *mat1;
    mat1=cvCloneMat(mat);
    for(i=size1/2;i<ywidth-size1/2;i++)
        for(j=size2/2;j<xwidth-size2/2;j++)
        {
            m=0;
            for(i1=0;i1<size1;i1++)
                for(j1=0;j1<size2;j1++)
                {
                    px=i-size1/2+i1;
                    py=j-size2/2+j1;
                    //CV_MAT_ELEM访问矩阵元素
                    m+=CV_MAT_ELEM(*mat,double,px,py)*a[i1*size1+j1];            
                }

                CV_MAT_ELEM(*mat1,double,i,j)=m;
        }
        return mat1;
}
//计算Ix2,Iy2,Ixy
CvMat *mbxy(CvMat *mat1,CvMat *mat2,int xwidth,int ywidth)
{
    int i,j;
    CvMat *mat3;
    mat3=cvCloneMat(mat1);
    for(i=0;i<ywidth;i++)
        for (j=0;j<xwidth;j++)
        {
            CV_MAT_ELEM(*mat3,double,i,j)=CV_MAT_ELEM(*mat1,double,i,j)*CV_MAT_ELEM(*mat2,double,i,j);
            
        }
        return mat3;
}

//用来求得响应度
CvMat *mbcim(CvMat *mat1,CvMat *mat2,CvMat *mat3,int xwidth,int ywidth)
{
    int i,j;
    CvMat *mat;
    mat=cvCloneMat(mat1);
    for(i = 0; i <ywidth; i++)
    {
        for(j = 0; j < xwidth; j++)
        {
            //注意：要在分母中加入一个极小量以防止除数为零溢出