Improving Marlin's compression ratio with partially overlapping codewords
Martinez, Manuel (Karlsruhe Institut für Technologie)
Sandfort, Kai (Karlsruhe Institute of Technology)
Dubé, Danny (Université Laval (Canadà))
Serra Sagristà, Joan (Universitat Autònoma de Barcelona. Departament d'Enginyeria de la Informació i de les Comunicacions)

Imprint:	IEEE, 2018
Description:	10 p.
Abstract:	Marlin [1] is a Variable-to-Fixed (VF) codec optimized for decoding speed. To achieve its speed, Marlin does not encode the current state of the input source, penalyzing compression ratio. In this paper we address this penalty by partially encoding the current state of the input in the lower bits of the codeword. Those bits select which chapter in the dictionary must be used to decode the next codeword. Each chapter is specialized for a subset of states, improving compression ratio. At the same time, we use one victim chapter to encode all rare symbols, increasing the efficiency of the rest of them. The decoding algorithm remains the same, only now codewords have overlapping bits. Mapping techniques allow us to combine common chapters and thus keep an efficient use of the L1 cache. We evaluate our approach with both synthetic and real data sets, and show significant improvements in low entropy sources, where compression efficiency can improve from 93. 9% to 98. 6%.
Grants:	Ministerio de Economía y Competitividad TIN2015-71126-R Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-691
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Language:	Anglès
Document:	Comunicació de congrés ; Capítol de llibre
Subject:	Data compression ; Lossless compression ; Variable-to-fix compression
Published in:	Data Compression Conference. Snowbird, Utah, USA, : 2018, p. 325-334, ISBN 978-1-5386-4883-4

DOI: 10.1109/DCC.2018.00041

Postprint 11 p, 366.7 KB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Engineering > Group on Interactive Coding of Images (GICI)
Books and collections > Book chapters