How to draw contour on edge [border outer ] in the objects?

How to draw contour on edge [border outer ] in the objects?

Answer 1

[Image Analyst]

Threshold the image. Call imdilate() if you want to enlarge it. Then call bwboundaries() and plot().

[Selva Karna]

Thanks so much Image Analyst , i got it.....

[Selva Karna]

Answer 2

[KSSV]

Use find to get the x,y coordinates of the respective pixels and use boundary

[Selva Karna]

I tried this approach always, but i get error, so u have any commands,

[KSSV]

Why errors? Show us the code..