Fig. 5. Binary anti-faking QR codes.

a₁ POM image of PS-BPLCs at Stage IV with low magnification. a₂ The image obtained after the gray-level conversion of a₁. a₃ An image of the binarization of a₂. a₄ The binary codes obtained from a₃ after pixelation and encoding processes. a₅ Large-scale ternary QR code with a pixel resolution of 37 × 37 encoded from a₁ undergoing ternary and pixelation processes. b₁–b₃ The magnified image of the orange squared area in a₁–a₃. b₄–b₅ The binary and ternary codes of the orange-squared area in a₄, a₅. In binary codes, the “black” or “white” pixel represents “0” or “1”. In ternary codes, the “green”, “blue”, or “black” pixels in a₅, b₅ represents “2”, “1”, or “0”.