Multiresolution fragile watermarking using complex chirp signal for content integrity verification

This paper proposes a wavelet-domain multiresolution fragile watermarking scheme using an improved quantization-index-modulation (QIM) embedding technique. A secure embedding zone is exploited in our proposed scheme to reduce the false detection rate of Kundur´s scheme. The frequency modulated (FM) complex chirp signal is employed as watermark. Both the real and the imaginary parts of the chirp signal are embedded simultaneously in a hierarchical manner. Unlike the conventional schemes, the proposed scheme does not require the original watermark for content integrity verification. The blind authentication process allows embedding of arbitrary FM chirp watermarks.