Data hiding in fingerprint images

Following the emergence and success of biometric identification systems as a powerful and irrefutable tool for security-aware architectures, it became evident that ensuring the authenticity of the biometric data itself is a challenging research problem. Furthermore, the “open” nature of this type of data makes it extremely vulnerable against typical processing attacks present in biometric acquisition hardware and software. In this paper, we propose a robust watermarking system to authenticate the biometric data. To enable the watermark robustness, we embed the watermark payload using the most important features of the biometric images. We propose image edges, determined by the wavelet maxima points, to quantify the robust feature points pertaining to the biometric images. The feature points, wavelet maxima, are modified in a way to ensure watermark imperceptibility while achieving high robustness. Also, geometric-invariance is achieved because the wavelet maxima representations are capable of adjusting the sampling grid when the host images are translated. Finally, performance results are reported to illustrate the robustness of the proposed watermarking system.