Fragile watermarking with improved tampering localisation and self-recovery capabilities

This paper presents a new image fragile watermarking method aimed at affording higher tampering localisation accuracy and self-recovery capabilities. First, the distorted regions are roughly localised by means of a secure block-wise mechanism resilient to cropping. An additional pixel-wise mechanism is proposed to refine the tampering localisation map and estimate the value of the distorted pixels prior to the manipulation. We present experimental comparisons between the proposed method and a scheme reported in recent literature. Results show that our method compares favourably to the existing scheme in terms of tampering localisation and self-recovery performance. Furthermore, we show that the proposed scheme is capable of partially recovering pixels in missing regions, when the cover image has been cropped.