DWT based key scheduled substitution and diffusion approach to full encryption

Cognitive growth of computer communication lead to radical improvement in wireless technology and shrunken the world into palms of user. During storing and sharing, avoiding third party access of data is a challenge. Image encryption is a popular technique widely used in the present scenario to protect secret information. Encryption achieves this by converting original data into unintelligible form. This paper discusses a key scheduled full encryption scheme based on Discrete Wavelet Transform (DWT). The DWT transformed image is subjected to key scheduled cryptographic procedure involving substitution and diffusion process so as to produce the final encrypted image. Restoring of encrypted image at the receiver side follows the reverse of encryption process.