Quantum compression

Quantum compression

The Quantum compression format is a somewhat obscure data compression method invented by a company called "Cinematronics" (written by an author identified as "David Stafford"). Rights to it were purchased at some point by Microsoft, and "Quantum" is one of the possible compression methods in a CAB archive.

Quantum (.Q) archiver

For DOS, PAQ.EXE is the compressor and UNPAQ.EXE is the decompressor. QWIN.EXE is the Windows decompressor (no Windows compressor exists). It is much faster and has more features (e.g., selective decompression) than the DOS decompressor. Each of these require at least a 386 CPU to run.

The latest known version is "0.97" (as of 15 May, 1995).

.Q archive header

This is immediately followed by the list of files:

(*) Strings are prefixed with their length. This takes one or twobytes. If the length is less than 128 then it is stored directly in onebyte. If it is greater than 127 then the high bit of the first byte isset to 1 and the remaining fifteen bits contain the actual length inbig-endian format.

Immediately following the list of files is the compressed data.

External links

*http://www.speakeasy.org/~russotto/quantumcomp.html
*ftp://ftp.sac.sk/pub/sac/pack/quant097.zip


Wikimedia Foundation. 2010.

Игры ⚽ Нужен реферат?

Look at other dictionaries:

  • Quantum (disambiguation) — In general, a quantum (plural: quanta) is a usually small, well distinguished portion (quantity or amount) of something.* In physics, quantum is an elementary indivisible entity. In particular ** Quantum physics includes several types of theories …   Wikipedia

  • Decoding Reality — Decoding Reality: The Universe as Quantum Information   Front Cover …   Wikipedia

  • Ross Williams — infobox person name=Ross Williams birth place = Melbourne, Victoria, Australia nationality = AustralianRoss Neil Williams is an Australian computer scientist and entrepreneur who has made significant contributions to data compression and… …   Wikipedia

  • Teleportation quantique — Téléportation quantique Cet article fait partie de la série Mécanique quantique Postulats de la mécanique quantique Histoire …   Wikipédia en Français

  • Téléportation quantique — La téléportation quantique est un protocole de communications quantiques consistant à transférer l’état quantique d’un système vers un autre système similaire et séparé spatialement du premier en mettant à profit l’intrication quantique.… …   Wikipédia en Français

  • Digital Linear Tape — A Super DLT I tape cartridge Digital Linear Tape (DLT) (previously called CompacTape) is a magnetic tape data storage technology developed by Digital Equipment Corporation (DEC) from 1984 onwards. In 1994 the technology was purchased by Quantum… …   Wikipedia

  • mechanics — /meuh kan iks/, n. 1. (used with a sing. v.) the branch of physics that deals with the action of forces on bodies and with motion, comprised of kinetics, statics, and kinematics. 2. (used with a sing. v.) the theoretical and practical application …   Universalium

  • cosmos — /koz meuhs, mohs/, n., pl. cosmos, cosmoses for 2, 4. 1. the world or universe regarded as an orderly, harmonious system. 2. a complete, orderly, harmonious system. 3. order; harmony. 4. any composite plant of the genus Cosmos, of tropical… …   Universalium

  • Scramjet — Part of a series on Aircraft propulsion Shaft engines (to drive pr …   Wikipedia

  • Entropy (information theory) — In information theory, entropy is a measure of the uncertainty associated with a random variable. The term by itself in this context usually refers to the Shannon entropy, which quantifies, in the sense of an expected value, the information… …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”