Mathematical morphology is a method applied in
image processing. The basic idea is to measure and
extract the corresponding shape from image with
structural elements for image processing and analyzing.
Using mathematical morphology to detect the edge is
better than using differential treatment, because it is not
sensitive to noise, and the edge extracted is relatively
smooth. Binary image is also known as black-and-white
image. The object can be easily identified from the
image background[20]. Combination of binary image and
mathematical morphology was adopted to detect edge,
which can reduce the noise and invalid edges, and make
the edge detection more smooth and accurate.