Text compression: Difference between revisions

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=== Dual-tile encoding ===
=== Dual-tile encoding ===


Dual-tile encoding, or DTE for short, is a special case of dictionary compression. In this case, the dictionary strings are all two bytes long.
Dual-tile encoding, or DTE for short, is a special case of dictionary compression. It is also known as [[https://en.wikipedia.org/wiki/Byte_pair_encoding byte-pair encoding]], or digram coding.
In this case, the dictionary strings are all two bytes long.


== Bitrate reduction methods ==
== Bitrate reduction methods ==

Revision as of 13:06, 28 April 2016

Text compression refers to techniques that allow fitting more text data into a smaller space.

Dictionary compression

Without recursion

With recursion

Dual-tile encoding

Dual-tile encoding, or DTE for short, is a special case of dictionary compression. It is also known as [byte-pair encoding], or digram coding. In this case, the dictionary strings are all two bytes long.

Bitrate reduction methods

Fixed-bit encoding

When the character set is small, such as 64 characters at most, strings could be encoded in a bitstream that packs 6 bits per character rather than 8 bits per character. This results in 20 % reduction of data size.

Variable-bit encodings

Huffman encoding

LZ based methods