how to fill color into image, by considering small matrix size 3*3 or 6*6? in opencv

Question

我如何通过考虑3 * 3的小矩阵为Mat类型的所需图像填充颜色，我在网上搜索了一下，但找不到正确的答案来实现，希望你们能有所帮助，在此先感谢，或者否则，请上传一些链接。

Answer 1

How can i fill color to required image of type Mat?

If you want to change the value of a Mat image, you can do as follows:

• Grayscale ( 8UC1 ):

   uchar intensity = img.at<uchar>(y, x) = value_you_want_to_fill; 

• Color image ( BGR color ordering, the default format returned by imread ):

   img.at<Vec3b>(y, x) = Vec3b(B_value, G_value, R_value);