Index


T-Y

Time domain

The way of representing a signal where the vertical deflection is the signal's amplitude, and the horizontal deflection is the time variable.

Traffic security

A collection of techniques for concealing information about a message to include existence, sender, receivers, and duration. Methods of traffic security include call-sign changes, dummy messages, and radio silence.

Transformation analysis

The process of detecting areas of image and sound files that is unlikely to be affected by common transformations and hide information in those places. The goal is to produce a more robust watermark.

Transform domain techniques

Various methods of signal and image processing (Fast Fourier Transform, Discrete Cosine Transform, etc.) used mainly for the purpose of compression.

Vector image

A digital image that is created through a sequence of commands or mathematical statements that places lines and shapes in a given two-or three-dimensional space.

Visible watermark

A visible and translucent image that is overlaid on a primary image. Visible watermarks allow the primary image to be viewed, but still marks it clearly as property of the owner. A digitally watermarked document, image, or video clip can be thought of as digitally "stamped."

Visible noise

The degradation of a cover as a result of embedding information. Visible noise will indicate the existence of hidden information.

Watermarking

A form of marking that embeds copyright information about the artist or owner.

Wrapper

See Cover medium.

XOR

The XOR (exclusive-OR) gate acts in the same way as the logical "either/or." The output is "true" if either, but not both, of the inputs are "true." The output is "false" if both inputs are "false" or if both inputs are "true." Another way of looking at this circuit is to observe that the output is 1 if the inputs are different, but 0 if the inputs are the same.

YCbCr

A setting used in the representation of digital images. Y is the luminance component; Cb,Cr are the chrominance components.




Investigator's Guide to Steganography
Investigators Guide to Steganography
ISBN: 0849324335
EAN: 2147483647
Year: 2003
Pages: 220

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