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Full-Text Articles in Computer Engineering
E-Fraud Prevention Based On The Self-Authentication Of E-Documents, Jonathan Blackledge, Eugene Coyle
E-Fraud Prevention Based On The Self-Authentication Of E-Documents, Jonathan Blackledge, Eugene Coyle
Conference papers
We consider a method for preventing e-Fraud in which a binary image is encrypted with a floating point cipher using a convolution operation and the output quantized into a 1-bit array generating a binary image ciphertext. The output is then ‘embedded’ in a host image to hide the encrypted information. Embedding is undertaken either in the lowest 1-bit layer or multiple 1-bit layers. Decryption is accomplished by: (i) extracting the binary image from the host image; (ii) correlating the result with the original cipher. In principle, any cipher generator can be used for this purpose and the method has been …
Self-Authentication Of Audio Signals By Chirp Coding, Jonathan Blackledge, Eugene Coyle
Self-Authentication Of Audio Signals By Chirp Coding, Jonathan Blackledge, Eugene Coyle
Conference papers
This paper discusses a new approach to ‘watermarking’ digital signals using linear frequency modulated or ‘chirp’ coding. The principles underlying this approach are based on the use of a matched filter to provide a reconstruction of a chirped code that is uniquely robust in the case of signals with very low signal-to-noise ratios. Chirp coding for authenticating data is generic in the sense that it can be used for a range of data types and applications (the authentication of speech and audio signals, for example). The theoretical and computational aspects of the matched filter and the properties of a chirp …