errors when running a function

this what happens whenever I click the complement button

Answer 1

[DGM]

It's unclear what situation you're in. It appears that you don't have Image Processing Toolbox. I thought that im2gray() was part of IPT, but it's possible that I'm wrong. If you don't have IPT, you won't be able to use imcomplement. For class-agnostic image inversion see this answer:

https://www.mathworks.com/matlabcentral/answers/247553-how-to-create-function-to-invert-image-colors#answer_1083548

[nour]

how can I download IPT because I searched for it and i can't find it

[DGM]

IPT (Image Processing Toolbox) is fairly common among non-base toolboxes, but if it's not something you have, it might be found via:

https://www.mathworks.com/products/image.html

otherwise, MIMT is here:

https://www.mathworks.com/matlabcentral/fileexchange/53786-image-manipulation-toolbox

Note that IPT and MIMT themselves are not equivalent, but in this case, IPT imcomplement() and MIMT iminv() are equivalent. Also, I should remind that the linked copy of iminv() requires neither MIMT nor IPT.

[nour]

thank you