Towards a telltale watermarking technique for tamper-proofing

In this paper we present a novel fragile watermarking scheme for the tamper-proofing of multimedia signals. Unlike previously proposed techniques, the novel approach provides spatial and frequency domain information on how the signal is modified. We call such a technique a telltale tamper-proofing method. Our design embeds a fragile watermark in the discrete wavelet domain of the signal by quantizing the corresponding coefficients with user-specified keys. Tamper detection is possible in the localized spatial and frequency regions of the given signal. We provide analysis, simulations and comparisons with two other tamper-proofing methods to show the potential of the proposed approach in detecting and characterizing the distortion imposed on the signal