How to draw a rectangle on a image?

I am trying to draw a rectangle on a image.

box =[100 200 200 200]

im=imread(im); figure, imshow(im)

hold on rectange = rectangle('Position', box, 'FaceColor','k')

Everytime the image gets displayed but without the rectangle. Please help me.

Answer 1

[DGM]

I'm going to guess that whatever the image was, it was either too small for the specified rectangle to be in-frame, or it was large, and the rectangle was being placed in a dark region.

box =[100 200 100 100];
im=imread('peppers.png'); 
imshow(im)
hold on
rectangle('Position', box, 'FaceColor','k')