A Novel Robust Colour Watermarking Scheme for Colour Watermark Images in Frequency Domain

Abstract

Digital colour watermarking has become essential and important copyright protection schemes in multimedia industry. Distribution of digital documents, especially colour images, over the internet has also become increasingly cost-efficient and widespread. The increased importance of digital media brings new challenges for securing the distribution of digital multimedia to make it both profitable for the document owner and reliable for the customer. This paper presents a novel and robust colour watermarking scheme of embedding colour watermark into colour host image. The technique shows efficient extraction of watermark with high PSNR of embedded image. The proposed algorithm is experimented in frequency domain in which combination of DWT and DCT is applied on the host image. The high energy content of colour watermark i.e. low frequency DCT coefficients are embedded into mid frequency DCT coefficients of high frequency components of multi resolved host colour image. The proposed algorithm is more secure, robust and efficient because of use of DWT and DCT. Performance evaluation and testing of the proposed algorithm using standard benchmarks reveals that it is fairly robust against a wide range of signal and image processing operations.