find luminance vector in an image

yi = 0.299ri  +0.587gi  +0.114bi        i=1,2,.M

Let Y the luminance vector computed starting from the palette P of the image
I.
Palette consist of RGB value...

What is the matlab code to find Yi value

Answer 1

[Azzi Abdelmalek]

If Im is your nxmx3 rgb image

yi=Im(:,:,1)*0.299+Im(:,:,2)*0.587+Im(:,:,3)*0.114

[Anusha]

This RGB is a colormap of an image?

Answer 2

[Walter Roberson]

 Y = 0.299 * R + 0.587 * G + 0.114 * B

where R, G, B are the vectors or arrays of R, G, and B values.