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how to extract rgb color image from surface height colormap

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Hi all, I wrote the code attached below. what i wish to do now (and not sure how) is create an RGB image from the colors that are defined by the Z values. so lets say that in the given example the color at each point will translate to a pixel then i will have a 61X61 RGB color image. how can i do that ?
[X,Y] = meshgrid(-3:0.1:3,-3:0.1:3);
Z=peaks(X,Y);
%Geneating the colors for the colormap
colors=[0,0.6,1;
0,0.6,1;
0.95,0.95,0.95;
0.953,0.64,0.375;
0,1,0;
1,1,1;
1,1,1];
colors_number=size(colors,1);
colors_interp = interp1(1:colors_number,colors,1:0.1:colors_number);
% Draw the surface
h=surf(X,Y,Z,'edgecolor','none');
colormap(colors_interp);

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Accepted Answer

Guillaume
Guillaume on 11 Mar 2015
See the tip section of caxis for an explanation of how matlab maps the Z values to a colour map index. So:
mapbounds = caxis;
numcolours = size(colors_interp, 1);
mapindex = fix((Z-mapbounds(1)) / (mapbounds(2) - mapbounds(1)) * numcolours) + 1;
mapindex(mapindex < 1) = 1;
mapindex(mapindex > numcolours) = numcolours;
img = ind2rgb(mapindex, colors_interp);
imshow(img);

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