A new non-expansion visual cryptography scheme with high quality of recovered image

In the traditional visual cryptography scheme, a secret pixel will be encoded into a block, causing the size of recovered image is larger than the original one. Thus, later studies attempt to improve these shortcomings, distortion of the recover image and a higher transmission cost. This paper proposes a visual secret sharing (VSS) scheme without expansion, and gets a better recovered result than other schemes due to the consideration of black pixels´ distribution.