A file archiver with high compression ratio. The brainchild of Igor Pavlov, this free software for Windows is based on the LZMA algorithm. Both LZMA and 7z were designed to provide high compression, fast decompression, and low memory requirements for decompression.

A complex and efficient audio compression method. AAC is an extension of and the successor to mp3. Like mp3, AAC is a time/frequency (T/F) codec that employs a psychoacoustic model to determine how the normal threshold of the ear varies in the presence of masking sounds. Once the perturbed threshold is known, the original audio samples are converted to frequency coefficients which are quantized (thereby providing lossy compression) and then Huffman encoded (providing additional, lossless, compression).

A perceptual audio coded designed by Dolby Laboratories to support several audio channels.

A very efficient text compression method by G. Buyanovsky (Section 8.3). It uses a dictionary with unbounded contexts and contents to select the context that best matches the search buffer and the content that best matches the look-ahead buffer.

A compression method that modifies its operations and/or its parameters according to new data read from the input stream. Examples are the adaptive Huffman method of Section 2.9 and the dictionary-based methods of Chapter 3.

Two-dimensional or three-dimensional geometric transformations, such as scaling, reflection, rotation, and translation, that preserve parallel lines (Section 4.35.1).

The set of all possible...