snldstep.m

超声图像实时消噪实验程序

    function r = snldStep( L, c )
    % Discrete numerical scheme of dL/dt for scalar diffusion
    N = size(L, 1);
    M = size(L, 2);
        cpc = translateImage( c, 1, 0 );
        cmc = translateImage( c, -1 , 0);
        ccp = translateImage( c, 0, 1 );
        ccm = translateImage( c, 0, -1 );
        Lpc = translateImage( L, 1, 0 );
        Lmc = translateImage( L, -1, 0 );
        Lcp = translateImage( L, 0, 1 );
        Lcm = translateImage( L, 0, -1 );
        r = ( (cpc+c).*(Lpc-L) - (c+cmc).*(L-Lmc) + ...
              (ccp+c).*(Lcp-L) - (c+ccm).*(L-Lcm) ) / 2;