LZHUF

Revision as of 14:52, 12 September 2021

This article is about the compression software by Haruyasu Yoshizaki. For the data compression technique in general, see LZ77 with Huffman coding.

LZHUF, or LZHUF.C, is a file compression utility written by Haruyasu Yoshizaki and Haruhiko Okumura. Some versions have a third author, Kenji Rikitake.

It uses LZSS-flavored LZ77, combined with adaptive Huffman coding. It has a 4K history buffer. The LZ77 code is from Okumura's LZARI.

Format details

Files have a minimal header, containing the uncompressed file size. The format is not portable, because it differs depending on the compiler's in-memory format of the "long" data type.

Related formats

• LZARI (predecessor)

Formats that use LZHUF compression, or something very similar, include:

• LHarc "lh1" compression
• CrLZH
• StuffIt "LZAH" compression
• Freeze/Melt
• ARC (compression format) v7 "Trimmed" compression
• Disk Masher System "Deep" compression

Software

There are many different versions of LZHUF.C in existence, with modifications by many different people. It's not clear how many "official" versions there were, or how they ought to be identified.

Note that the original source code has portability issues. It will not work correctly if compiled by a modern C compiler.

For a discussion of the terms of use, see lbrate → lzhuf-post.txt.

• http://cd.textfiles.com/powerprogramming/PROGTOOL/COMPRESS/LZHSRC10.ZIP → LZHUF.C - "English version 1.0 / Based on Japanese version 29-NOV-1988 / LZSS coded by Haruhiko OKUMURA / Adaptive Huffman Coding coded by Haruyasu YOSHIZAKI / Edited and translated to English by Kenji RIKITAKE"
• http://cd.textfiles.com/rbbsv3n1/pac4/okumura.zip → LZHUF.C - "written by Haruyasu Yoshizaki 11/20/1988 / some minor changes 4/6/1989 / comments translated by Haruhiko Okumura 4/7/1989"
• http://cd.textfiles.com/pcmedic9310/UTILS/COMPRESS/OKUMURA2.ZIP → LZHUF.C
• http://cd.textfiles.com/simtel/simtel20/MSDOS/ARCUTILS/LZ_COMP2.ZIP → LZHUF.C
• LHarc at old-dos.ru → LARC and LHarc sources → LZHUF.C

Links

• History of Data Compression in Japan
• okumura.zip → COMPRESS.TXT