How to choose one contour?

Using the syntax "contour", 8 concentric contours are plotted around a surface. However, I only need the outer most contour. How could I get only the outer most contour? (using "contour(image,1)", I will get the inner most contour!)

Answer 1

[Jan]

From the documentation of contour:

 To display a single contour line at a particular value, define v as a
 two-element vector with both elements equal to the desired contour level.

So all you have to do is to define k properly. Or:

[C,h] = contour(image, 8)

And now select the wanted elements from the output.

[Shahin Safazadeh]

Thank you, Jan. So, I can customize "h". It worked very nice. Great ...