Namco's data compression method in Ace Combat 3, Ace Combat 51), and Time Crisis.
The Ulz format is an implementation of Lz77 algorithm with a ring buffer.
archives begin with
Ulz (55 6C 7A 1A hexadecimal, or 1A7A6C55
little endian)
AC3ES Tools (decompression & recompression, with source code)
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Timeline
1995: Namco releases Time Crisis (ULZ 1.00)
1999: Namco releases Ace Combat 3 (ULZ 1.05)
2004: Namco releases Ace Combat 5 (ULZ 1.05)
2011-01-04: modder
McCuñao posts an incomplete description of ULZ “from a friend”
3)
2012-03-11: modder
Gipphe analyzes the format
4), but gives up – his texts and code is lost
2012-06-20: modder
CUE posts incomplete decompression code for
Time Crisis and
Ace Combat 3 5)
2014-02-08: modder
esperknight posts incomplete decompression code for
Ace Combat 3 6)
2014-08-02:
esperknight posts full decompression code
7)
2017-01-10: modder
Infrid unites the two separate compression methods into one
8)