What is Bottom-Hat transformation? I am reading the Digital Image Processing book by Gonzalez and i can't seem to understand Bottom-hat transformation. Can anyone explain it to me in easy terms?
The explanation in Wikipedia for Top-hat transform - Properties seems pretty simple, for the bottom-hat, another name for the black top-hat.

The black top-hat returns an image, containing the &quot;objects&quot; or
&quot;elements&quot; that:

are &quot;smaller&quot; than the structuring element,
are darker than their surroundings.