Change white pixels to invisible
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Hi, I have a .png I'm trying to overlay on top of an existing figure in matlab. Most of the image is just a white background. Is it possible to overlay everything but the white background from the .png to the existing figure? In other words, can I make the white background transparent/invisible?
The image is RGB 'unit8'. When I do this:
alphachannel = all(image == 255, 3);
imwrite(image,'invisible.png','Alpha',alphachannel);
This error comes up:
Error using writepng>parseInputs (line 349)
The value of 'alpha' is invalid. Expected input to be one of these types:
double, uint8, uint16
Instead its type was logical.
When I do this:
alphachannel = double(all(image ~= 255, 3));
imwrite(image,'invisible.png','Alpha',alphachannel);
The .png file appears to have the invisible pixels instead of the white pixels, but ,when I try to overlay the new .png on top of the existing figure in matlab, the "invisible" background is black. Is there anything I can do? Any help is appreciated, thanks.
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