Spread Transform Watermarking for Digital Multimedia Using the Complex Wavelet Domain

Complex wavelets offer several improvements over their discretely sampled counterparts such as improved directionality and shift invariance allowing for better representation of image features. This has important implications for watermark embedding and modelling of the human visual system that is important to satisfy the imperceptibility requirement of watermarking systems. In addition spread transform watermarking has emerged as a method of combining the advantages of spread spectrum and quantization based data hiding algorithms, offering improved levels of capacity and robustness. This paper applies spread transform embedding and the complex wavelet domain to the case of grey scale, colour image and video watermarking.