Application of Lempel–Ziv factorization to the approximation of grammar-based compression
نویسندگان
چکیده
منابع مشابه
Application of Lempel-Ziv Factorization to the Approximation of Grammar-Based Compression
We present almost linear time (O(n · log |Σ|) time) O(log n)ratio approximation of minimal grammar-based compression of a given string of length n over an alphabet Σ and O(k · log n) time transformation of LZ77 encoding of size k into a grammar-based encoding of size O(k · log n). Computing exact size of the minimal grammar-based compression is known to be NP -complete. The basic novel tool is ...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2003
ISSN: 0304-3975
DOI: 10.1016/s0304-3975(02)00777-6