Data Hiding Technique Using Secure Spread-Spectrum and Discrete Wavelet Transform

Abstract

This project focuses on implementing various techniques of watermarking as nowadays chunks of data are being embedded on digital media or distributed over the internet. Digital watermarking is the process of hiding a message related to digital signals in different forms like an image, song, video within the signal itself. The data which is distributed can be replicated easily without error, putting the rights of their owners at risk. When encrypted for distribution, the information can easily be decrypted and copied. The best way to discourage illegal copying is to insert information known as watermark, into the important data in such a way that it is impossible to separate the watermark from the data. In this project, a secure spread-spectrum watermarking algorithm for the digital images is implemented using discrete wavelet transform (DWT). The algorithm applied is such that the watermark i.e, the message to be inserted in the form of logo is being embedding into the host cover image. In this, the watermark is spread over many different frequency bins so that each bin contains very little amount of energy and certainly undetectable. Robustness and image quality of the proposed method is calculated by Normalized Correlation (NC) and Peak Signal to Noise Ratio (PSNR). The performance of the proposed algorithm has been tested against various signal processing attacks. We found that the method is robust against different attacks.