Edge image computation algoritm,Urgent plz reply

Algorithm: (edge image computation) 1. Read the image and convert it to gray scale. 2. Blur the image using a Gaussian filter. 3. Compute the gradient map of the blurred image. 4. Compute GVF. (100 iterations and ? = 0.2 ) 5. Filter out only strong edge responses using ks , where s is the standard deviation of the GVF. (k – value used is 2.5). 6. Converge onto edge pixels satisfying the force balance condition yielding edge image.

I found GVF i mean upto 4th step,but how to perform 5 th step,6th step,and any one please tell me how to find internal force.Plz provide code for 5th and 6th steps

Answer 1

[Sean de Wolski]

Show us what you've done and what the MATLAB-related errors are. We won't do your homework assignment for you.

Answer 2

[KARTHIK]

function Fext = AM_GVF(f, mu, in, normalize)

    fmin  = min(f(:));
    fmax  = max(f(:));
    f = (f-fmin)/(fmax-fmin);           % Normalize f to the range [0,1]
    if ndims(f)==2,
        [fx,fy] = AM_gradient(f);       % Calculate the gradient of the edge map
        fz = 0;
    else
        [fx,fy,fz] = AM_gradient(f);    % Calculate the gradient of the edge map
    end
    u = fx; v = fy; w = fz;             % Initialize GVF to the gradient
    SqrMagf = fx.*fx + fy.*fy + fz.*fz; % Squared magnitude of the gradient field
    % Iteratively solve for the GVF u,v,w
    for i=1:in,
        u = u + mu*AM_laplacian(u) - SqrMagf.*(u-fx);
        v = v + mu*AM_laplacian(v) - SqrMagf.*(v-fy);
        if ndims(f)==3,
            w = w + mu*AM_laplacian(w) - SqrMagf.*(w-fz);
        end
    end
    if ndims(f)==2,
        Fext = cat(3,u,v);
    else
        Fext = cat(4,u,v,w);
    end
    if normalize,
        Fmag = sqrt(sum(Fext.^2,ndims(f)+1));
        if ndims(f)==2,
            Fext = Fext./(Fmag(:,:,[1 1])+eps);
        else
            Fext = Fext./(Fmag(:,:,:,[1 1 1])+eps);
        end
    end

I am getting GVF of an image,but i am unable to undestand how to filter strong edge responses and how to find internal force in a force balance condition,where GVF is external force.