|v. t.||1.||To press or squeeze together; to force into a narrower compass; to reduce the volume of by pressure; to compact; to condense; |
|2.||To embrace sexually.|
|3.||(Computers) to reduce 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 compressed data is usually decompressed to recover the initial data format before subsequent use.|
|n.||1.||(Surg.) A folded piece of cloth, pledget of lint, etc., used to cover the dressing of wounds, and so placed as, by the aid of a bandage, to make due pressure on any part.|
|Noun||1.||compress - a cloth pad or dressing (with or without medication) applied firmly to some part of the body (to relieve discomfort or reduce fever)|
|Verb||1.||compress - make more compact by or as if by pressing; "compress the data"|
|2.||compress - squeeze or press together; "she compressed her lips"; "the spasm contracted the muscle"|
|1.||compress - To feed data through any compression algorithm.|
|2.||(tool)||compress - The Unix program "compress", now largely
supplanted by gzip.|
Unix compress was written in C by Joseph M. Orost, James A. Woods et al., and was widely circulated via Usenet. It uses the Lempel-Ziv Welch algorithm and normally produces files with the suffix ".Z".
Compress uses variable length codes. Initially, nine-bit codes are output until they are all used. When this occurs, ten-bit codes are used and so on, until an implementation-dependent maximum is reached.
After every 10 kilobytes of input the compression ratio is checked. If it is decreasing then the entire string table is discarded and information is collected from scratch.