Wavelet Methods in Steganography

Abstract

This paper is devoted to graphic information protection by means of computer steganography using wavelet techniques. The methods of the image processing using digital watermarking are classified. Some research of the structure of the digital image is investigated. In the first solution the steganographic system, which uses a discrete wavelet transform for embedding of grayscale watermark into wavelet coefficients of grayscale container is mоdeled and realized. Stego image is achieved by the inverse discrete wavelet transform. Binarization using halftoning algorithm is considered as a kind of powerful attack to stego image. After binarization attack the extracted watermark was found to have acceptable visual quality. The degradation of the embedded digital watermark after binarization is estimated using human visual system. Corresponding conclusions on steganographic system stability are drawn. In the second solution we propose the steganographic scheme which uses the proposed wavelet basis images.