Question

Is there a way to get the content of a contourf plot as an image matrix? I want rasterize only the content, not the axes, labels and the empty space of the entire figure.

My goal is to overlay a transparent, colored contour plot over a grayscale image and I don’t see another way, since MATLAB has only one colormap per figure.

Answer 1

Try getframe and frame2im

Example from the frame2im documentation:

Create and capture an image using getframe and frame2im:

peaks                      %Make figure
f = getframe;              %Capture screen shot
[im,map] = frame2im(f);    %Return associated image data 
if isempty(map)            %Truecolor system
  rgb = im;
else                       %Indexed system
  rgb = ind2rgb(im,map);   %Convert image data
end