Image Sharing with Steganography and Authentication - Visual Cryptography and Secret Image Sharing - page 430

FIGURE 16.11
The neighboring pixels that accepted error diffusion for Case 1.

FIGURE 16.12
The neighboring pixels that accepted error diffusion for Case 2.

Loop: if (i = 1) or i = H + 2)j(j = 1) or (j= W+2)! EGI(i,j) = 0;
else EGI(i;j) = GI(i 1;j 1);

Step 3: for i = 2:H + 1, j = 2:W + 1

Loop: if EGI(i;j) TH !EHI(i,j) = 255;
else EHI(i,j) = 0;
E(i,j) = EGI(i,j)-EHI(i,j);
EGI(i,j + 1) = EGI(i,j + 1) +E(i;j) Wr;
EGI(i + 1,j) = EGI(i,j + 1) +E(i;j) Wb;
EGI(i + 1,j + 1) = EGI(i + 1,j + 1) +E(i;j) Wb;
EGI(i + 1,j - 1) = EGI(i + 1,j - 1) + E(i;j) Wbl;

Step 4: for i = 1:H, j = 1:W

HI(i,j) = EHI(i + 1, j + 1).