A Comparative Study of Digital Watermarking Techniques in Frequency Domain
Source: HELWAN UNIVERSITY
Digital watermarking is hiding the information inside a digital media. Its widely used in copyright protection of digital images .This paper presents a comparative study of digital watermarking techniques in frequency domain and explores the role of Discrete cosine transform DCT, Discrete wavelet transform DWT and Contourlet transform CT in generating robust embedding technique that resist various attacks. The experimental results show the superiority of CT-based watermarking over DWT and DCT watermarking techniques, the quality of the watermarked image is excellent, it can include huge amount of hidden data, but it's not much better than other techniques in resisting attacks.