what is the meaning of "red and green narrow bands filtered by monochromatic filter"

Question

Manu Gowda 2023-5-20

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1968334-what-is-the-meaning-of-red-and-green-narrow-bands-filtered-by-monochromatic-filter

评论： Manu Gowda 2023-5-20

Hii, I want to know what is the meaning of applying "monochromatic filters to R and G channels of RGB images" and how to impliment these filters in MATLAB.

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

DGM 2023-5-20

I give up. What does it mean?

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2023-5-20

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1968334-what-is-the-meaning-of-red-and-green-narrow-bands-filtered-by-monochromatic-filter#answer_1240064

在 MATLAB Online 中打开

Example:

img = imread('flamingos.jpg');

imshow(img); title('original');

R = img(:,:,1);

G = img(:,:,2);

B = img(:,:,3);

Rmask = R > 200 & R < 240;

Gmask = G > 50;

imshow(Rmask); title('red mask');

imshow(Gmask); title('green mask');

overallmask = cast(Rmask & Gmask, 'like', img);

filtered_R = R .* overallmask;

filtered_G = G .* overallmask;

filtered_B = B .* overallmask;

filtered = cat(3, filtered_R, filtered_G, filtered_B);

imshow(filtered); title('filtered')

2 个评论
显示无隐藏无

Walter Roberson 2023-5-20

A monocromatic filter is a filter that is applied to only one of the color channels (at at time, anyhow.)

For example, the flamingos image has orange flamingos and pink flamingos, but orange and pink are not pure Red or Green or Blue, and can only be detected as combinations of those colors. If you were to examine only the Red channel, then you would not be able to isolate the orange flamingos. But sometimes there are useful things that can be done if you work channel by channel.

Manu Gowda 2023-5-20