dilates the grayscale, binary, or packed binary image IM, returning the dilated image, IM2. The argument SE is a structuring element object, or array of structuring element objects, returned by the strel or offsetstrel function.
If IM is logical, the structuring element must be flat and imdilate performs binary dilation. Otherwise, imdilate performs grayscale dilation. If SE is an array of structuring element objects, imdilate performs multiple dilations of the input image, using each structuring element in succession.