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ALPHAMASK: semi-transparent image overlay

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Overlay image with semi-transparent mask and return handle

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ALPHAMASK: Overlay image with semi-transparent mask

Overlays a semi-transparent mask over an image. By default the
currently displayed figure is overlain.
Options include overlay colour and opacity.
Returns a handle to the overlay mask.

Usage:
hOVM = alphaMask(bwMask, [colour, transparency, axHandle])
bwMask: logical matrix representing mask
colour: vector of three rgb values in range [0, 1] (optional; default [0 0 1])
transparency: scalar in range [0, 1] representing overlay opacity (optional; default 0.6)
axHandle: handle to axes on which to operate (optional; default current axes)
hOVM: handle to overlay image is returned

Example:
figure;
I = peaks(200);
bwMask = eye(200);
imshow(I, [], 'Colormap', hot);
alphamask(bwMask, [0 0 1], 0.5);

See also IMSHOW, CREATEMASK

Comments and Ratings (6)

bourr houssam

Thank you davis, that's exactly what i'm looking for

David

David (view profile)

Works.

Zoé

Zoé (view profile)

Andrew Davis

Thanks for the comment, Scott. I was using the square brackets to indicate that those arguments are optional, but I can see how it could be construed to mean that the last three arguments should be given as a single vector. Maybe alphamask(bwMask, [colour], [transparency], [axHandle]) would be more clear...

Scott

Scott (view profile)

Great function. FYI, you have a small typo in your usage comments. Line 10 should read:
% hOVM = alphamask(bwMask, [colour], transparency, axHandle)

Lili

Lili (view profile)

MATLAB Release
MATLAB 7.12 (R2011a)
Acknowledgements

Inspired by: Image overlay

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