How to combine two palettes inside one image?

Is it possible to combine two palettes inside one image? For example, using main part of the image with gray palette, but some stressed part of it, inside circle, for example, with jet palette?

Thank you

Answer 1

[Image Analyst]

Yes, there are several ways. You can make up a mask, and then apply the colormap to the whole indexed image and create an RGB image from it, then you can turn the grayscale image into a color image, and then use the mask to replace inside the mask with the pseducolored RGB image.

Or you can add an offset to the circular part so that it lies in a different gray scale range and then make a colormap that is a color one and gray one combined, and then apply that colormap to the image with colormap.

Which way do you prefer?

[Valeriy]

Thanks a lot, Image Analyst, for your, as usually very informative and useful answer.

For the moment I practically realized your second proposal: by mask treatment I decreased background level, outside of the circle, and in such a way circular area became well stressed. But I have lack of knowledge how to transfer indexed image into RGB one or visa versa? Should I manually calculate R,G,B components of final image and from them buid it? I suppose that should exist some dedicated Matlab operation.

[Walter Roberson]

ind2rgb()