Author Topic: LZMA (Lempel–Ziv–Markov)  (Read 390 times)

Offline macStuff

  • Platinum Member (500+ Posts)
  • *****
  • Posts: 1346
  • http://www.OldschoolDAW.com
    • OldschoolDAW.com
LZMA (Lempel–Ziv–Markov)
« on: June 02, 2019, 01:01:47 AM »
https://en.wikipedia.org/wiki/Lempel%E2%80%93Ziv%E2%80%93Markov_chain_algorithm

The Lempel–Ziv–Markov chain algorithm (LZMA) is an algorithm used to perform lossless data compression. It has been under development since either 1996 or 1998 by Igor Pavlov[1] and was first used in the 7z format of the 7-Zip archiver. This algorithm uses a dictionary compression scheme somewhat similar to the LZ77 algorithm published by Abraham Lempel and Jacob Ziv in 1977 and features a high compression ratio (generally higher than bzip2)[2][3] and a variable compression-dictionary size (up to 4 GB),[4] while still maintaining decompression speed similar to other commonly used compression algorithms.[5]

LZMA2 is a simple container format that can include both uncompressed data and LZMA data, possibly with multiple different LZMA encoding parameters. LZMA2 supports arbitrarily scalable multithreaded compression and decompression and efficient compression of data which is partially incompressible. However, it is claimed to be unsafe and less efficient than LZMA.[6]

Offline ELN

  • Gold Member (200+ Posts)
  • *****
  • Posts: 276
  • new to the forums
Re: LZMA (Lempel–Ziv–Markov)
« Reply #1 on: June 02, 2019, 09:55:13 PM »
LZSS (Lempel–Ziv–Storer–Szymanski) is a related algorithm used in the NewWorld ROMs. The canonical C implementation was written my Haruhiko Okumura in 1989, and passed around extensively.

I have ported it to Python here, as part of a dump/build toolkit. https://github.com/elliotnunn/tbxi/blob/master/tbxi/slow_lzss.py

Offline macStuff

  • Platinum Member (500+ Posts)
  • *****
  • Posts: 1346
  • http://www.OldschoolDAW.com
    • OldschoolDAW.com
Re: LZMA (Lempel–Ziv–Markov)
« Reply #2 on: June 03, 2019, 07:03:28 AM »
perhaps u could find time to take a look at the roms that ive posted in the storage section and see what files u can extract from them with LZS

actually i think daniel posted them on my site ill pm you the link