How do I tune a color scale to a matrix image?

Hi, I have a problem with my other programming tool and have to use MatLab to draw a 2D map with the specific color scale. The function is basically like mat2gray(), only difference is that instead of the gray color scale, I need it to be like the color scale in the image attached.

Answer 1

[jonas]

You can easily draw your matrix with a specific colormap. You don't need to convert it to an image beforehand.

A=peaks;
imagesc(A);
colormap(bone);

If you then want the image data, you can just type

I = getframe;

and then you can treat is as an image

imshow(I.cdata)

[Shang Gao]

Sorry, but my color scale is not bone. I am not sure how to get the exact rgb mixture to make it look alike.

[jonas]

It was just an example. Just stack the colors of a single column of your colorscale and use it as colormap. If I is the RGB matrix of your colorbar, then I(:,1,:) contains the RGB triplets of your colormap. Just reshape it from nx1x3 to a nx3 matrix.

Can give you code in a bit if you dont figure it out. On mobile atm.

[jonas]

Here you go

A=peaks;
imagesc(A);
I=imread('image.png')
cmap=im2double([I(:,1,1) I(:,1,2) I(:,1,3)])
colormap(cmap);