DWT versus DCT Based Hybrid Steganography and Watermarking Technique for Color Image Encryption.

Abstract

Comprehensive studies have been done to develop strong encryption technology, which plays a vital role in multimedia transmission and communications. High robustness against various types of attacks is the main requirement of any encryption method. Many algorithms have been suggested for encryption, but most of them suffer from weak efficiency. In this paper, two proposed algorithms for color image encryption will be provided to get high robustness against composite attacks with improved performance. The composite attacks might be in one of two different forms: friendly or hard. Encryption techniques could be represented by hybrid of steganography and watermarking. Discrete Wavelet Transform (DWT) and Discrete Cosine Transform (DCT) have been used for image transformation with the proposed techniques. After intensive comparative studies with some traditional methods, it has been got that the new algorithms have given better performance over that of the traditional ones.