How to do "the black top-hat transformation"

after filtering the image i want to perform a black top hat transformation but could not find any information about it. please, any one help me .

Answer 1

[Image Analyst]

Perhaps you're talking about the "bottom hat filter".

IM2 = imbothat(IM,SE) performs morphological bottom-hat filtering on the grayscale or binary input image, IM, returning the filtered image, IM2. SE is a structuring element returned by the strel function. SE must be a single structuring element object, not an array containing multiple structuring element objects.

[Ashim Chakraborty]

thank you

Answer 2

[Pekko Tuominen]

In Matlab, the black top-hat transform is called bottom-hat and the white top-hat transform is called tophat. This should remove your confusion.

Answer 3

[MD AMIR SOHAIL]

White Top-hat Filtering: ( Original Image - Opening of original Image ) [which is imtophat() in matlab]

Black Top-hat Filtering: ( Closing of Original Image - Original Image ) [which is imbothat() in matlab ]

Answer 4

[Jos (10584)]

http://uk.mathworks.com/help/images/ref/imtophat.html

[Ashim Chakraborty]

Hi jos thank you for your comment. I tried it already but the output is appearing different. there are two different types of top hat is black and white. I am looking for the black top hat which not mentioned anywhere and the code IM2 = imtophat(IM,SE) IM2 = imtophat(IM,NHOOD) gpuarrayIM2 = imtophat(gpuarrayIM,___) giving different output.