[syn: compression, compressing]
The Collaborative International Dictionary of English v.0.48:
Compression \Com*pres"sion\, n. [L. compressio: cf. F.
1. The act of compressing, or state of being compressed.
"Compression of thought." --Johnson.
2. (Computers) reduction of the space required for storage
(of binary data) by an algorithm which converts the data
to a smaller number of bits while preserving the
information content. The act of compressing .
Note: Compression may be lossless compression, in which all
of the information in the original data is preserved,
and the original data may be recovered in form
identical to its original form; or lossy compression,
in which some of the information in the original data
is lost, and decompression results in a data form
slightly different from the original. Lossy
compression is used, for example, to compress audio or
video recordings, and sometimes images, where the
slight differences in the original data and the data
recovered after lossy compression may be
imperceptable to the human eye or ear. The JPEG
format is produced by a lossy compression algorithm.
WordNet (r) 3.0 (2006):
n 1: an increase in the density of something [syn: compaction,
compression, concretion, densification]
2: the process or result of becoming smaller or pressed
together; "the contraction of a gas on cooling" [syn:
compression, condensation, contraction]
3: encoding information while reducing the bandwidth or bits
required [ant: decompression]
4: applying pressure [syn: compression, compressing] [ant:
Moby Thesaurus II by Grady Ward, 1.0:
74 Moby Thesaurus words for "compression":
abbreviation, abridgment, abstract, agglutination, apocope,
astriction, astringency, bottleneck, cervix, circumscription,
clamping, clamping down, clumping, clustering, coarctation,
compactedness, compaction, compressure, concentration, concretion,
condensation, consolidation, conspectus, constriction,
constringency, contraction, contracture, crush, curtailment,
decrease, densification, diminuendo, elision, ellipsis, epitome,
foreshortening, hardening, hourglass, hourglass figure, isthmus,
knitting, narrow place, narrowing, neck, nip, pinch, precis, press,
pressure, puckering, pursing, recap, recapitulation, reduction,
retrenchment, shortening, solidification, squeeze, squeezing,
stranglement, strangulation, striction, stricture, summary,
summation, syncope, synopsis, systole, telescoping, tightening,
truncation, tweak, wasp waist, wrinkling
The Free On-line Dictionary of Computing (18 March 2015):
1. (Or "compaction") The coding of data to save
storage space or transmission time. Although data is already
coded in digital form for computer processing, it can often be
coded more efficiently (using fewer bits). For example,
run-length encoding replaces strings of repeated characters
(or other units of data) with a single character and a count.
There are many compression algorithms and utilities.
Compressed data must be decompressed before it can be used.
The standard Unix compression utilty is called compress
though GNU's superior gzip has largely replaced it. Other
compression utilties include pack, zip and PKZIP.
When compressing several similar files, it is usually better
to join the files together into an archive of some kind
(using tar for example) and then compress them, rather than
to join together individually compressed files. This is
because some common compression algorithms build up tables
based on the data from their current input which they have
already compressed. They then use this table to compress
subsequent data more efficiently.
See also TIFF, JPEG, MPEG, Lempel-Ziv Welch,
Web Content Compression FAQ
Usenet newsgroups: news:comp.compression,
2. Reducing the dynamic range of an audio signal,
making quiet sounds louder and loud sounds quieter. Thus,
when discussing digital audio, the preferred term for reducing
the total amount of data is "compaction". Some advocate this
term in all contexts.