Object delete using boundary points

Object delete using boundary points

Post by Bil » Fri, 14 Jan 1994 19:09:44



I need to delete an object in a binary image for which I have a list of the boundary
points. There may be other objects in the image. The boundary is 8-way connected.
I think that the following algorithm should work:

if no. of boundary points =< 3 then
        delete boundary points
else
        // search for a point inside the object which is 4-way connected
        for each boundary point (x, y)
                if (x+1, y+1) has 4-way connectivity then
                        perform 4-way connected flood fill with (x+1, y+1) as the
                          seed
                endif
        endfor
        repeat the above loop with the following offsets until all boundary
                points have been deleted
                (x-1, y-1), (x+1, y), (x-1, y), (x, y+1), (x, y-1),
                (x+1, y-1), (x-1, y+1), (x-1, y+1), (x, y)
        if after using all the above offset some of the boundary points haven't
                been deleted then delete boundary points
endif

Has anyone any suggestions for improvements, alternative algorithms or source code
(perferrably C)?

Thanks.

Bill.

 
 
 

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