Use left mouse clicks to draw a closed polygon. A double left click ends the polygon drawing. Then you can select from a list of image processing operations that will be applied only inside the ROI polygon. Those operations work pretty well for grey images but regarding color images they may be very slow. That happens because the whole color image has to be transformed into an intensity space (YIQ in current case) and back to RGB, and those are slow operations and VERY memory demanding as far as Matlab is respected. So, even if you start with an indexed image you'll end up with a true color (RGB) image.
Copyright © <2010>, <Joaquim Luis>
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