Digital Image Watermarking Using BWT

The drastic advancement of digital technologies has demanded the owners to pay immense attention in securing their digital contents. Of late, watermarking has been utilized by researchers for the security of digital documents. However the embedded watermark data can be easily hacked by the hackers and thus result as a threat to protection of digital content. The proposed method is an efficient scheme for protecting the copyrights of digital images with the aid of both biometrics and digital watermarking. Newer data hiding techniques that satisfy the requirements of imperceptibility, robustness, capacity, or data hiding rate and security of the hidden data etc., are being developed. Therefore the preference to go for digital image watermarking, to show resiliency against various unintentional or deliberate attacks has increased. In this paper implementation of two different watermarking algorithms in the frequency domain will be presented. The first algorithm is based on the Discrete Wavelet Transform (DWT), the second one is based on the Bi-orthogonal Wavelet Transform (BWT). Embedding the watermark is done by modifying the coefficients of the middle frequency band within region of non-interest (RONI) so that the visibility of the image and diagnosis capability will not be affected and the watermark will not be removed by attacks. All schemes are tested using medical images and the simulation results are compared and the comparison shows that the best scheme is that based on using BWT.