如标题所言，此处是对于灰度图像而言

///method 1 read the image data one by one

	for (int row = 0, i = 0;row < imgDst.rows;row++)

	{

		for (int col = 0;col < imgDst.cols;col++)

		{

			cout << setw(3) << (int)imgDst.at<uchar>(row, col) << " ";

			arr[i] =imgDst.at<uchar>(row, col) ;

			//cout << (int)arr[i] << " ";

			i++;

		}

		cout << endl;

	}

	//test to print

	for (int q = 0;q < imgDst.rows;q++)

	{

		for (int k = 0;k < imgDst.cols;k++)

		{

			int pos = q*imgDst.cols + k;

			cout << setw(3) << (int)arr[pos] << " ";

		}

		cout << endl;

	}

///method 2 memcpy the image data to uchar arr in rows

	unsigned char *imgData = new unsigned char[vec_Num];//直接将图像数据拷贝到数组中;

	memcpy(imgData, imgDst.data, imgDst.rows*imgDst.cols*sizeof(unsigned char));

	for (int i = 0;i < vec_Num;i++)

	{

		arr[i] = (float)(imgData[i])/255;

	}

	//test to print

	for (int q = 0;q < imgDst.rows;q++)

	{

		for (int k = 0;k < imgDst.cols;k++)

		{

			int pos = q*imgDst.cols + k;

			cout << setw(3) << (int)arr[pos] << " ";

		}

		cout << endl;

	}

	cout << endl;