A SECURE BIT - LEVEL IMAGE ENCRYPTION BY USING SELECTION BASED 1 - D CHAOTIC MAPS

With the increasing demand for data exchange over the internet, data encryption has become crucial in order to provide protection against various malicious attacks. To reinforce an encryption algorithm, operations at bit-level is carried out as it plays a vital role in the encryption process. In order to achieve this, bit-level confusion and diffusion-based image encryption are proposed in this chapter. In addition, block-level diffusion operation is performed to ensure multi-fold security. The bit-level confusion and diffusion operations change both the pixel positions and pixel values simultaneously resulting in an increased level of security. In this algorithm, the bit-level confusion operation depends on the selection based 1-D chaotic maps while the selection process depends on the original image. This generates more confusion for the attacker. The proposed algorithm resists both the known-plaintext attack and the chosen-plaintext attack very efficiently because of the dependency of secret keys on the original image. The main advantages of this algorithm are the improved randomness and improved security in the encrypted image. Simulation results and security analysis indicate that the proposed encryption algorithm is highly effective and provides relatively higher security against the most common attacks.