selecting all pixels in an image based on RBG criteria

[mike]

Dear All,

I was wondering if there is a way to select all pixels in an image based on RBG criteria. In other-words, every pixel in an image should have a certain Red, Green and Blue value from 0-255. Is there a way that I can select all pixels in an image based on these values. For example...

select all pixels close to white
Red: 230 - 255
Green: 230 - 255
Blue: 230-255

or, select red pixels
Red: 180 - 255
Green: 0-50
Blue: 0-50

Does this exist anywhere?

Thank you very much for you consideration.

Sincerely,

Mike