Indexing Compressed Text
نویسنده
چکیده
As a result of the rapid growth of the volume of electronic data, text compression and indexing techniques are receiving more and more attention. These two issues are usually treated as independent problems, but approaches of combining them have recently attracted the attention of researchers. In this thesis, we review and test some of the more effective and some of the more theoretically interesting techniques. Various compression and indexing techniques are presented, and we also present two compressed text indices. Based on these techniques, we implement an compressed full-text index, so that compressed texts can be indexed to support fast queries without decompressing the whole texts. The experiments show that our index is compact and supports fast search.
منابع مشابه
Self-Indexing XML
Self-indexing is a technology that integrates text compression and text indexing, such that a text collection can be simultaneously compressed and indexed. The resulting representation, called a self-index of the text, takes space close to that of the compressed text, is able of reproducing any text substring, and oers indexed searching of the collection. This has been a major breakthrough in t...
متن کاملCompression-Domain Text Indexing and Retrieval
Keyword-based text retrieval engines have been and will continue to be essential to text-based information access systems because they serve as the basic building blocks to high-level text analysis systems. Traditionally, text compression and text retrieval are teated as independent problems. Text les are compressed and indexed separately. To answer a keyword-based query, text les are rst uncom...
متن کاملIndexing Compressed Text
We present a technique to build an index based on suux arrays for compressed texts. We also propose a compression scheme for textual databases based on words that generates a compression code that preserves the lexicographical ordering of the text words. As a consequence it permits the sorting of the compressed strings to generate the suux array without decompressing. As the compressed text is ...
متن کاملSelf-indexing Natural Language
Self-indexing is a concept developed for indexing arbitrary strings. It has been enormously successful to reduce the size of the large indexes typically used on strings, namely suffix trees and arrays. Selfindexes represent a string in a space close to its compressed size and provide indexed searching on it. On natural language, a compressed inverted index over the compressed text already provi...
متن کاملAn Algorithmic Framework for Compression and Text Indexing
We present a unified algorithmic framework to obtain nearly optimal space bounds for text compression and compressed text indexing, apart from lower-order terms. For a text T of n symbols drawn from an alphabet Σ, our bounds are stated in terms of the hth-order empirical entropy of the text, Hh. In particular, we provide a tight analysis of the Burrows-Wheeler transform (bwt) establishing a bou...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2003