This paper proposes a new fragile watermarking capable of perfectly restoring the original watermarked pixels of a tampered image. First, a secure block-wise mechanism, resilient to cropping, is used to localise tampered blocks of pixels. The authentic pixels and some reference bits are then used to estimate the original 5 most significant bits (MSBs) of the tampered pixels by means of an exhaustive and iterative restoration mechanism. Results are presented to demonstrate the restoration capabilities of the proposed mechanism.