ced.m

超声图像实时消噪实验程序

    function R = ced( L, k, obsscale, intscale, stepsize, nosteps, verbose)
    % ced: coherence enhancing diffusion
        if verbose
            figure(verbose);
            subplot(1,2,1); imshow(L,[]); title('Original Image'); drawnow;
        end
        R = L;
        for i = 1:nosteps
                Rx = gD( R, obsscale, 1, 0 );
                Ry = gD( R, obsscale, 0, 1 );
                s11 = gD( Rx.^2,  intscale, 0, 0 );
                s12 = gD( Rx.*Ry, intscale, 0, 0 );
                s22 = gD( Ry.^2,  intscale, 0, 0 );
                alpha = sqrt( (s11-s22).^2 + 4*s12.^2 );
                el1 = 1/2 * (s11 + s22 - alpha );
                el2 = 1/2 * (s11 + s22 + alpha );
                %%%%%%%%%%%%%%%%%%%%%%%
%                 delta = 1-b*(abs(0));
%                 c2 = a*delta;
%                 absub = (el1-el2).^2;
%                 if(absub<s2)
%                     c1 = c2*(1-absub./s2);
%                 else
%                     c1 = 0;
%                 end
                c1 = max(0.01, 1-exp( -(el1-el2).^2 / k^2 ));
                c2 = 0.01;
                d11 = 1/2 * (c1+c2+(c2-c1).*(s11-s22)./(alpha+eps));
                d12 = (c2-c1).*s12./(alpha+eps);
                d22 = 1/2 * (c1+c2-(c2-c1).*(s11-s22)./(alpha+eps));
                R = R + stepsize * tnldStep( R, d11, d12, d22  );
                if verbose
                    figure(verbose);
                    subplot(1,2,2); imshow(R,[]);
                    title('Coherence Enhancing Diffusion'); drawnow;
                end
        end