Color image to black and white converter

RGB to grayscale image conversion online:

Original image:
Converted image:

How to convert RGB to grayscale

Gray RGB color code has equal red,green and blue values:

 R = G = B

For each image pixel with red, green and blue values of (R,G,B):

R' = G' = B' = (R+G+B) / 3 = 0.333R + 0.333G + 0.333B

This formula can be changed with different weights for each R/G/B value.

R' = G' = B' = 0.2126R + 0.7152G + 0.0722B

Or

R' = G' = B'  = 0.299R + 0.587G + 0.114B

 

Example

Pixel with RGB values of (30,128,255)

The red level R=30.

The green level G=128.

The blue level B=255.

R' = G' = B' = (R+G+B) / 3 = (30+128+255) / 3 = 138

so the pixel will get RGB values of:

(138,138,138)

 


See also

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