matlab - Showing an image -

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i came matlab code first reads image , converts double follows:

i = double(imread(img));

after that, shows image follows:

imshow(i/max(i(:)))

what mean? when removed max part, got image white background. goal of such division? and, why show image when done , doesn't show image if directly show read image without division max?

thanks.

the expression:

i/max(i(:))

just normalises pixel values range 0..1.0. dividing pixel values max value.


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