Secure and Authentic DCT Image Steganography through DWT - SVD Based Digital Watermarking with RSA Encryption

With the rapid advance in digital network, digital libraries, and particularly WWW (World Wide Web) services, we can retrieve many kinds of information anytime. Thus, security has become one of the most significant problems for distributing new information. It is necessary to protect this information while communicated over insecure channels. Thus a need for developing technology that will help to provide security as well as authenticity. Steganography is the idea of hiding private or sensitive data or information within something that appears to be nothing out of the normal. Steganography and cryptography are similar in the way that they both are used to protect important information. Nowadays the term "Information Hiding" relates to both watermarking and steganography. So we proposed combined strategy of cryptography, steganography and digital watermarking to hide secure image with watermark logo inside cover image. For this purpose we use DCT, DWT, SVD and RSA approach. Using DCT, encrypted watermark logo (encryption perform using RSA) is hide inside Secure image, results in Stego image. This Stego image is hiding inside cover image using DWT and SVD. Our approach can be used to transmit secure information like copyright information of company, movie with their respective image, finger-print or thumb impression of particular person. This method can be used for security purpose. Thus would be beneficial to nation for over all security.