讀取圖片

Mat srcImage = imread(“image1.jpg”); 

srcImage.empty();

Mat grayImage;

cvtColor(srcImage,grayImage,CV_BGR2GRAY);

grayImage.at<char>(i,j) = 0;

顯示圖片

imshow("Picture",grayImage);    
waitKey(0); 

imwrite("gray.jpg",grayImage);
 

srcImage.release();

IplImage *srcImage = cvLoadImage("potota.jpg", CV_LOAD_IMAGE_UNCHANGED);

IplImage *grayImage =  cvCreateImage(cvGetSize(src), IPL_DEPTH_8U, 1);  

cvZero(*grayImage);

cvCvtColor(srcImage, grayImage, CV_BGR2GRAY);

IplImage *binImage = cvCreateImage(cvGetSize(grayImage), IPL_DEPTH_8U, 1);
cvZero(*binImage); 
cvThreshold(grayImage,*binImage,128,1,CV_THRESH_BINARY_INV);
 

CvSize size = cvGetSize(srcImage);
int h = size.height
int w = size.width

CV_IMAGE_ELEM(src,uchar,i,j) = 0;

cp_src = cvCreateImage(cvGetSize(srcImage), IPL_DEPTH_8U, 1);
cvCopy(src,cp_src,NULL);

CvScalar s = cvGet2D(srcImage,i,j);

s = CV_RGB(0,255,0);
cvSet2D(srcImage,i,j,s);
 

cvShowImage("Skeleton",srcImage);
cvWaitKey(0);
cvDestroyWindow("Skeleton");

cvReleaseImage(&srcImage);

熟悉opencv1的操作，有利於自己以後去 看前輩們寫的程式碼的思路。
明白什麼意思就行 然後根據意思 自己可以寫opencv3版本的程式碼