加载图像和遍历像素（OpenCV）

#include <iostream>
using namespace std;
#include <opencv2\opencv.hpp>
using namespace cv;
void main() {
	Mat imgMat = imread("0_depth.png");
	imshow("原图", imgMat);
	cout << imgMat.channels() << endl;
	Mat imgGray;
	cvtColor(imgMat, imgGray, CV_RGB2GRAY);
	cout << imgGray.channels() << endl;
	int nRows = imgGray.rows;
	int nCols = imgGray.cols * imgGray.channels();
	cout << nRows << endl;
	cout << nCols << endl;
	for (int j = 0; j < nRows; j++) {
		uchar* data = imgGray.ptr<uchar>(j);
		for (int i = 0; i < nCols; i++) {
			if (data[i]!=0) {
				cout << data[i] << endl;
			} 
		}
	}
	imshow("处理后的图像", imgGray);
	waitKey(0);
	system("pause");
}