What exactly is "the input image"?
I did not find a method to create a 100% equal copy of a displayed figure. There can be 1 or 2 pixels difference, except I use the Java methods for a screen copy. But even then it is not trivial to get the contents of the figure exactly, because there can be different borders around the figure.
In addition MATLAB's HG objects must not be set on exact pixel positions, e.g. when using 'normalized' units -- in opposite to Java, as far as I understood. But e.g. MATLAB's GUI elements are based on Java objects and of course theire pixels are drawn to exact screen pixel positions...
When I create a UITable and UITree in a figure, resizing the figure let sometimes disappear the 1-pixel light grey line on the left (indowsXP, Matlab 2009a). It is hard to notice, but gets more striking, when a slider is created directly at the margin of the figure.
My conclusion: If an exact [WxH] output is needed, crop the captured matrix - at the right and/or left and top and/or bottom.
