Authentication Watermarking Using Integer Wavelet Transform

In a cryptography based authentication watermarking, a message authentication code of the whole image is computed and the resulting code is inserted into the image itself. This paper proposes an efficient authentication watermarking scheme using integer wavelet transform. The already existing spatial domain technique is applied in wavelet domain. Embedding data in wavelet domain offers high degree of robustness against common image processing operations. The proposed scheme reduces the number of required prioritized sub-blocks to be half. To embed k-bits of secret data, the proposed scheme requires only k/2 sub blocks. The scheme is suitable for both small and large images. It detects any alteration while maintaining good visual quality.