Re: Can gray image’ pixel value be negative?

lijing wrote:
Want to normalize an gray image to zero mean and unit variance, but
now I wonder could a gray image’ pixel value be negative? I have never
seen. Could you give some explanation?

It's a matter of the image encoding. If you want a zero mean, then of course some pixel values must be negative (if the image is non-trivial, that is). There is nothing wrong with this. If you want to display this again later, you need to add the bias again, of course.

So long,
Thomas
.

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