A Bit-level Selective Image Encryption Algorithm based on Chaos

This paper presents a bit-level image encryption algorithm, which can protect the important bit-planes with respect to the content of plain-image. The plain-image is initially transform to a binary image and decomposed into 8 bitplanes. Then, the similarities among the binary image and each bitplane are measured, and we get an important index array of the 8 bitplanes. Next, the top k important bitplanes are encrypted. Finally, all the bitplanes are combined into the cipher-image. The experimental results of sufficient security analyses demonstrate that proposed algorithm can offer efficient image protection.