Detection in quantization-based watermarking: performance and security issues
Luis Pérez-Freire, Pedro Comesaña, Fernando Pérez‐González · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2005
In this paper, a novel method for detection in quantization-based watermarking is introduced. This method basically works by quantizing a projection of the host signal onto a subspace of smaller dimensionality. A theoretical performance analysis under AWGN and fixed gain attacks is carried out, showing great improvements over traditional spread-spectrum-based methods operating under the same conditions of embedding distortion and attacking noise. A security analysis for oracle-like attacks is also accomplished, proposing a sensitivity attack suited to quantization-based methods for the first time in the literature, and showing a trade-off between security level and performance; anyway, this new method offers significant improvements in security, once again, over spread-spectrum-based methods facing the same kind of attacks.