mapping luminosity -> colour gradient

Hello.

I have a black and white image. Id like to smoothly map the luminosity values to rgb values in the image.

An example would be a black and white image of a cloudy sky. Id like to colorize the image so that eg. the brightest clouds stay white, the darkest clouds become a reddish blue, the midrange luminosity values become a bright yellow etc. I suppose in general Im looking for a way to map luminosity values to colours in a gradient, where Ideally I can define/create the gradient as I please. Even better would be where I can alter the mapping on the fly so that I change the mapping/gradient in retrospect at any time without altering the original/underlying image pixels (ie the luminosity information).

Id be very grateful for any good suggestions on how to best achieve such an effect.
Thanks in Advance.

Peter Williams wrote:

Hello.

I have a black and white image. Id like to smoothly map the luminosity values to rgb values in the image.

An example would be a black and white image of a cloudy sky. Id like to colorize the image so that eg. the brightest clouds stay white, the darkest clouds become a reddish blue, the midrange luminosity values become a bright yellow etc. I suppose in general Im looking for a way to map luminosity values to colours in a gradient, where Ideally I can define/create the gradient as I please. Even better would be where I can alter the mapping on the fly so that I change the mapping/gradient in retrospect at any time without altering the original/underlying image pixels (ie the luminosity information).

Id be very grateful for any good suggestions on how to best achieve such an effect.
Thanks in Advance.

Check out gradient map – I think it will do exactly what you want: smloothly
map a grayscale value to a color.
—

Mike Russell
www.curvemeister.com
www.geigy.2y.net

Hello.

I have a black and white image. Id like to smoothly map the luminosity values to rgb values in the image.

An example would be a black and white image of a cloudy sky. Id like to colorize the image so that eg. the brightest clouds stay white, the darkest clouds become a reddish blue, the midrange luminosity values become a bright yellow etc. I suppose in general Im looking for a way to map luminosity values to colours in a gradient, where Ideally I can define/create the gradient as I please. Even better would be where I can alter the mapping on the fly so that I change the mapping/gradient in retrospect at any time without altering the original/underlying image pixels (ie the luminosity information).

Id be very grateful for any good suggestions on how to best achieve such an effect.
Thanks in Advance.