A DWT Based Approach for Image Steganography
Po‐Yueh Chen, Hung‐Ju Lin · 2006
Abstract: In this paper we propose a new steganography technique which embeds the secret messages in frequency domain. According to diferent users ’ demands on the embedding capac-ity and image quality, the proposed algorithm is divided into two modes and 5 cases. Unlike the space domain approaches, secret messages are embedded in the high frequency coefficients re-sulted from Discrete Wavelet Transform. Coefficients in the low frequency sub-band are pre-served unaltered to improve the image quality. Some basic mathematical operations are per-formed on the secret messages before embedding. These operations and a well-designed map-ping Table keep the messages away from stealing, destroying from unintended users on the inter-net and hence provide satisfactory security.