Editing Visual cryptography (section)

== Visual steganography ==
[[File:visual_cryptography_stenography.svg|thumb|Overlaying component images with letters A and B to reveal the letter S]]
2×2 subpixels can also encode a binary image in each component image, as in the scheme on the right. Each white pixel of each component image is represented by two black subpixels, while each black pixel is represented by three black subpixels.

When overlaid, each white pixel of the secret image is represented by three black subpixels, while each black pixel is represented by all four subpixels black. Each corresponding pixel in the component images is randomly rotated to avoid orientation leaking information about the secret image.<ref>M. Pramanik, Kalpana Sharma, [http://semanticscholar.org/paper/d724f43a2f8ae4ace27f66997579b7871e0a2f75 ''Analysis of Visual Cryptography, Steganography Schemes and its Hybrid Approach for Security of Images''], Computer Science, 2014</ref>