How to calculate the image distance

How do I use bwdist() function to calculate the image d?

Answer 1

[Image Analyst]

Try this

d = bwdist(binaryImage);

The max value of (the badly-named) "d" will be the minimum distance from the centroid to the outline.

[tsai kai shung]

the centroid is circle centroid?

[Image Analyst]

The max of the distance transform is not necessarily located at the centroid of a blob, but for a circle it will be. If you need the centroid of an arbitrary shape use regionprops(). Then use bwboundaries to get the coordinates of all outline pixels, then use sqrt() to compute the distances and max() to find the one with max distance.