LZWL is a syllable-based variant of the LZW (Lempel-Ziv-Welch) compression algorithm, designed to work with syllables derived from any syllable decomposition algorithm. This approach allows LZWL to efficiently process both syllables and words, offering a nuanced method for data compression.
The LZWL algorithm initializes by populating a dictionary with all characters from the alphabet. It then searches for the longest string, S, that exists in both the dictionary and as a prefix of the unencoded portion of the input. The algorithm outputs the identifier of S and augments the dictionary with a new phrase, which combines S with the subsequent character in the input. The input position advances by the length of S. During decoding, LZWL addresses scenarios where the received phrase identifier does not exist in the dictionary by constructing the missing phrase from the concatenation of the last added phrase and its initial character.
Syllable-Based Adaptationedit
In its syllable-based adaptation, LZWL employs a list of syllables as its alphabet. The initialization step includes the empty syllable and integrates small, frequently occurring syllables into the dictionary. Identifying S and encoding its identifier mirrors the original algorithm, with the distinction that S represents a syllable string. If S is an empty syllable, the algorithm extracts a syllable K from the input and encodes K using methods for new syllables before adding K to the dictionary and advancing the input position accordingly.
Dictionary Expansionedit
A notable variation in the syllable-based LZWL involves dictionary expansion. When both S and the subsequent string S1 are non-empty syllables, a new phrase is added to the dictionary by concatenating S1 with S’s initial syllable. This method prevents the formation of strings from syllables that appear only once and ensures the decoder does not encounter undefined phrase identifiers.
Referencesedit
Data Compression Using the LZWL Algorithm
Salomon, David; Motta, Giovanni (2010-01-18). Handbook of Data Compression. Springer. ISBN 9781848829039. Google Books. Retrieved 2014-07-11.
Categoriesedit
April 09, 2024
lzwl, this, article, multiple, issues, please, help, improve, discuss, these, issues, talk, page, learn, when, remove, these, template, messages, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations. This article has multiple issues Please help improve it or discuss these issues on the talk page Learn how and when to remove these template messages This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources LZWL news newspapers books scholar JSTOR January 2013 Learn how and when to remove this template message This article s tone or style may not reflect the encyclopedic tone used on Wikipedia See Wikipedia s guide to writing better articles for suggestions August 2009 Learn how and when to remove this template message Learn how and when to remove this template message LZWL is a syllable based variant of the LZW Lempel Ziv Welch compression algorithm designed to work with syllables derived from any syllable decomposition algorithm This approach allows LZWL to efficiently process both syllables and words offering a nuanced method for data compression Contents 1 Algorithm 1 1 Syllable Based Adaptation 1 2 Dictionary Expansion 2 References 3 CategoriesAlgorithm editThe LZWL algorithm initializes by populating a dictionary with all characters from the alphabet It then searches for the longest string S that exists in both the dictionary and as a prefix of the unencoded portion of the input The algorithm outputs the identifier of S and augments the dictionary with a new phrase which combines S with the subsequent character in the input The input position advances by the length of S During decoding LZWL addresses scenarios where the received phrase identifier does not exist in the dictionary by constructing the missing phrase from the concatenation of the last added phrase and its initial character Syllable Based Adaptation edit In its syllable based adaptation LZWL employs a list of syllables as its alphabet The initialization step includes the empty syllable and integrates small frequently occurring syllables into the dictionary Identifying S and encoding its identifier mirrors the original algorithm with the distinction that S represents a syllable string If S is an empty syllable the algorithm extracts a syllable K from the input and encodes K using methods for new syllables before adding K to the dictionary and advancing the input position accordingly Dictionary Expansion edit A notable variation in the syllable based LZWL involves dictionary expansion When both S and the subsequent string S1 are non empty syllables a new phrase is added to the dictionary by concatenating S1 with S s initial syllable This method prevents the formation of strings from syllables that appear only once and ensures the decoder does not encounter undefined phrase identifiers References editData Compression Using the LZWL Algorithm Salomon David Motta Giovanni 2010 01 18 Handbook of Data Compression Springer ISBN 9781848829039 Google Books Retrieved 2014 07 11 Categories edit Retrieved from https en wikipedia org w index php title LZWL amp oldid 1212420196, wikipedia, wiki, book, books, library,
