How can I extend an edge?

Hi

I need to find the surrounding edge of a region. I used these lines but it don't give me a good result . log find an edge belonging to the region when I need to find the edge that surrounds the region. Is there a matlab function that extends the edge given by log 1 or 2 pixels

I=imread('image.jpg');
edg = edge(I,'log',0);

thankx

Answer 1

[Image Analyst]

No.

[Tomas]

thank you for your reply, is it possible to dilate the edge to the outside of the region. How can i correct these lines?

NHOOD = [ 0 1 0; 1 1 1; 0 1 0];
SE = strel('arbitrary', NHOOD);
Dilate = imdilate(Edge, SE);