灰度图像的一阶和二阶导数代码实现

#include 
#include 
#include 
#include "opencv2/highgui/highgui.hpp"
#include "opencv2/core/core.hpp"
#include   


using namespace cv;
using namespace std;


void kcvShowImageStretchAbs(const char* winName, const IplImage* img)
{
IplImage* imgAbs = cvCloneImage(img);
IplImage* img8u = cvCreateImage(cvGetSize(img), 8, img->nChannels);
cvAbs(img, imgAbs);
cvNormalize(imgAbs, img8u, 255, 0, CV_MINMAX);
cvNamedWindow(winName);
cvShowImage(winName, img8u);
cvReleaseImage(&imgAbs);
cvReleaseImage(&img8u);
}


int main()
{
IplImage*  src = cvLoadImage("20170502110711-666_看图王.jpg", 1);


IplImage* srcGray = cvCreateImage(cvGetSize(src), 8, 1);
IplImage* srcDx = cvCreateImage(cvGetSize(src), IPL_DEPTH_16S, 1);
IplImage* srcDy = cvCreateImage(cvGetSize(src), IPL_DEPTH_16S, 1);
IplImage* srcDxx = cvCreateImage(cvGetSize(src), IPL_DEPTH_16S, 1);
IplImage* srcDyy = cvCreateImage(cvGetSize(src), IPL_DEPTH_16S, 1);
IplImage* srcDxy = cvCreateImage(cvGetSize(src), IPL_DEPTH_16S, 1);


cvSetZero(srcDx);
cvSetZero(srcDy);
cvSet(srcDxx,cvScalarAll(255));
cvSet(srcDyy, cvScalarAll(255));
cvSet(srcDxy, cvScalarAll(255));


cvCvtColor(src,srcGray,CV_BGR2GRAY);
uchar* sptr = (uchar*)srcGray->imageData;
uchar* sptrNext = (uchar*)srcGray->imageData;
uchar* sptrPrev = (uchar*)srcGray->imageData;
int sstep = srcGray->widthStep/sizeof(char);
int w = srcGray->width;
int h = srcGray->height;


short* xptr = (short*)srcDx->imageData;
short* yptr = (short*)srcDy->imageData;
int xstep = srcDx->widthStep/sizeof(short);
int ystep = srcDy->widthStep /sizeof(short);


short* xxptr = (short*)srcDxx->imageData;
short* yyptr = (short*)srcDyy->imageData;
short* xyptr = (short*)srcDxy->imageData;
int xxstep = srcDxx->widthStep / sizeof(short);
int yystep = srcDyy->widthStep / sizeof(short);
int xystep = srcDxy->widthStep / sizeof(short);


sptrNext += sstep;
for (int i = 0; i < h - 1; i++, sptr += sstep, sptrNext += sstep, xptr += xstep, yptr += ystep)
{
for (int j = 0; j < w - 1;j++)
{
yptr[j] = sptrNext[j] - sptr[j];
xptr[j] = sptr[j + 1] - sptr[j];
}
}


//最后一行，复制上一行内容
short* xptrPrev = xptr - xstep;
short* yptrPrev = yptr - ystep;
for (int j = 0; j < w ; j++)
{
xptr[j] = xptrPrev[j];
yptr[j] = yptrPrev[j];
}
//最后一列，复制前一列内容
xptr = (short*)srcDx->imageData;
yptr = (short*)srcDy->imageData;
for (int i = 0; i < h; i++, xptr += xstep, yptr += ystep)
{
xptr[w - 1] = xptr[w - 2];
yptr[w - 1] = yptr[w - 2];
}

kcvShowImageStretchAbs("srcDx", srcDx);
kcvShowImageStretchAbs("srcDy", srcDy);


//指针归位,二阶导数求导
sptr = (uchar*)srcGray->imageData;
sptrNext = (uchar*)srcGray->imageData;
sptrPrev = (uchar*)srcGray->imageData;


sptrNext += 2*sstep;
sptr += sstep;
yyptr += yystep; xxptr += xxstep; xyptr += xystep;
for (int i = 1; i < h-1 ; i++, sptr += sstep, sptrNext += sstep, yyptr += yystep, xxptr += xxstep, xyptr += xystep)
{
for (int j = 1; j < w - 1; j++)
{
yyptr[j] = sptrNext[j] - 2 * sptr[j] + sptrPrev[j];
xxptr[j] = sptr[j + 1] - 2 * sptr[j] + sptr[j - 1];
xyptr[j] = sptrNext[j + 1] + sptr[j] - sptr[j + 1] - sptrNext[j];
}
sptrPrev = sptr;
}
//四周边界处理
xxptr = (short*)srcDxx->imageData;
yyptr = (short*)srcDyy->imageData;
xyptr = (short*)srcDxy->imageData;
for (int i = 0; i < h; i++, xxptr += xxstep, yyptr += yystep,xyptr += xystep)
{
xxptr[0] = xxptr[1];
xxptr[w - 1] = xxptr[w - 2];
yyptr[0] = yyptr[1];
yyptr[w - 1] = yyptr[w - 2];


xyptr[0] = xyptr[1];
xyptr[w - 1] = xyptr[w - 2];
}


xxptr = (short*)srcDxx->imageData;
yyptr = (short*)srcDyy->imageData;
xyptr = (short*)srcDxy->imageData;
short* xxptrNext = xxptr + xxstep;
short* yyptrNext = yyptr + yystep;
short* xyptrNext = xyptr + xystep;


for (int j = 0; j < w; j++)
{
xxptr[j] = xxptrNext[j];
yyptr[j] = yyptrNext[j];
xyptr[j] = xyptrNext[j];
}


xxptr += (h - 1)*xxstep;
yyptr += (h - 1)*yystep;
xyptr += (h - 1)*xystep;
short* xxptrPrev = xxptr - xxstep;
short* yyptrPrev = yyptr - yystep;
short* xyptrPrev = xyptr - xystep;

for (int j = 0; j < w; j++)
{
xxptr[j] = xxptrPrev[j];
yyptr[j] = yyptrPrev[j];
xyptr[j] = xyptrPrev[j];
}
kcvShowImageStretchAbs("srcDxx", srcDxx);
kcvShowImageStretchAbs("srcDyy", srcDyy);
kcvShowImageStretchAbs("srcDxy", srcDxy);

cvReleaseImage(&src);
cvReleaseImage(&srcGray);
cvReleaseImage(&srcDx);
cvReleaseImage(&srcDy);
cvReleaseImage(&srcDxx);
cvReleaseImage(&srcDyy);
cvReleaseImage(&srcDxy);


cvWaitKey(-1);
return 0;
}