An efficient fragile watermarking scheme for tamper localization in satellite images

The applications of satellite images in various fields like oceanography, agriculture, biodiversity conservation, forestry, landscape, geology, regional planning, intelligence, and warfare are growing at a burgeoning rate. As satellite images carry very sensitive information, they need a secure and verifiable transmission over the network. To address the sensitive authentication issue and making the satellite images verifiable, this paper proposes an efficient ROI-based blind fragile watermarking approach. The proposed approach bundles the capability to not only verify the integrity of the watermarked satellite image but can also localize the regions where any intentional or unintentional tampering occurred in the watermarked satellite images with more than 90% accuracy. The proposed approach also achieves a good imperceptibility between the cover and watermarked satellite image in terms of PSNR (Average 60 dB). In the proposed approach, eight dynamically evolved progenies are generated corresponding to every ROI pixel. These progenies are tightly associated with each other at the bit level. The proposed approach hosts a sequence of algorithms, which when applied to these progenies, generates an authentication bit for every corresponding ROI pixel. The generated authentication bit is then embedded into the different intensities of RONI pixels. The selection of the number of bits per pixel to embed the watermark is decided dynamically. Detailed experimental results using various subjective and objective evaluation parameters have been presented to substantiate the imperceptibility and tamper localization capabilities of our proposed approach.