Campus Livre
im2gray
Converts an RGB image to grayscale, leaving grayscale images as they are.
Category: Graphics > Images
Syntax
G = im2gray(I)Returns the luminance of an RGB image, or I itself when it is already 2-D.
Description
Each pixel becomes 0.2989*R + 0.5870*G + 0.1140*B, weights that follow how the eye sees brightness: green counts most and blue least. Unlike rgb2gray, im2gray accepts grayscale images, so it is safe to call without checking the input first.
Input arguments
I- RGB image (m-by-n-by-3) or grayscale image (m-by-n).
Output arguments
G- m-by-n grayscale image of the same class as
I.
Example
Red and green pixels
I = uint8(cat(3, [255 0], [0 255], [0 0]));
G = im2gray(I)Output
G = 1×2 uint8 row vector
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