Image Tamper Detection and Recovery by Intersecting Signatures

In this paper, we propose an exact image authentication scheme that can, in the best case, detect image tampering with the accuracy of one pixel. This method is based on constructing blocks in the image in such a manner that they intersect with one another in different directions. Such a technique is very useful to identify whether an individual image pixel has been tampered with. Moreover, the tampered region can be well recovered with the embedded recover data

Reversible watermarking scheme with image-independent embedding capacity

Permanent distortion is one of the main drawbacks of all the irreversible watermarking schemes. Attempts to recover the original signal after the signal passing the authentication process are being made starting just a few years ago. Some common problems, such as salt-and-pepper artefacts owing to intensity wraparound and low embedding capacity, can now be resolved. However, some significant problems remain unsolved. First, the embedding capacity is signal-dependent, i.e., capacity varies significantly depending on the nature of the host signal. The direct impact of this is compromised security for signals with low capacity. Some signals may be even non-embeddable. Secondly, while seriously tackled in irreversible watermarking schemes, the well-known problem of block-wise dependence, which opens a security gap for the vector quantisation attack and transplantation attack, are not addressed by researchers of the reversible schemes. This work proposes a reversible watermarking scheme with near-constant signal-independent embedding capacity and immunity to the vector quantisation attack and transplantation attack

AUTHENTICATION OF DIGITAL DOCUMENTS USING SECRET KEY BIOMETRIC WATERMARKING

Abstract -Digital documents play a major role in modern era. They are easy to generate, modify and manage. The easy modifiable property of digital document makes it more vulnerable to forgery. It can be easily tampered or forged. So the challenge is to produce digital documents that are highly resistant to forgery and reliably confirms the real owner of the document. This can be resolved by biometric watermarking which make a direct relation between the document and its owner. A new biometric watermarking technique with secret key is proposed to digitize the authoritative documents issued by government / other organizations as a part of UID / Aadhar card project of India using biometric watermarking. Biometric code is generated from the biometric data collected from the owner of the document. The biometric code is watermarked in the document with a secret key to generate a biometric watermarked document that authenticates the real owner. Dewatermarking the document with the same key yields the biometric code that can be used for authentication of the document. If the document is tampered in any way it will be indicated in the extracted watermark. Experimental results show that 100% accuracy is obtained in authenticating the genuine documents

Scalable authentication of MPEG-4 streams

schemes for authenticating MPEG-4 streams: the Flat Authenticatio