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Merging upstream version 1.7~rc1.

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Signed-off-by: Daniel Baumann <daniel@debian.org>
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doc/clzip.info
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@ -11,7 +11,7 @@ File: clzip.info, Node: Top, Next: Introduction, Up: (dir)
Clzip Manual
************
This manual is for Clzip (version 1.7-pre1, 26 February 2015).
This manual is for Clzip (version 1.7-rc1, 23 May 2015).
* Menu:
@ -38,8 +38,7 @@ File: clzip.info, Node: Introduction, Next: Algorithm, Prev: Top, Up: Top
Clzip is a lossless data compressor with a user interface similar to the
one of gzip or bzip2. Clzip is about as fast as gzip, compresses most
files more than bzip2, and is better than both from a data recovery
perspective. Clzip is a clean implementation of the LZMA
(Lempel-Ziv-Markov chain-Algorithm) "algorithm".
perspective.
Clzip uses the lzip file format; the files produced by clzip are
fully compatible with lzip-1.4 or newer, and can be rescued with
@ -136,7 +135,7 @@ multivolume compressed tar archives.
Clzip is able to compress and decompress streams of unlimited size by
automatically creating multi-member output. The members so created are
large, about 64 PiB each.
large, about 2 PiB each.

File: clzip.info, Node: Algorithm, Next: Invoking clzip, Prev: Introduction, Up: Top
@ -144,13 +143,14 @@ File: clzip.info, Node: Algorithm, Next: Invoking clzip, Prev: Introduction,
2 Algorithm
***********
There is no such thing as a "LZMA algorithm"; it is more like a "LZMA
coding scheme". For example, the option '-0' of lzip uses the scheme in
almost the simplest way possible; issuing the longest match it can find,
or a literal byte if it can't find a match. Inversely, a much more
elaborated way of finding coding sequences of minimum price than the one
currently used by lzip could be developed, and the resulting sequence
could also be coded using the LZMA coding scheme.
In spite of its name (Lempel-Ziv-Markov chain-Algorithm), LZMA is not a
concrete algorithm; it is more like "any algorithm using the LZMA coding
scheme". For example, the option '-0' of lzip uses the scheme in almost
the simplest way possible; issuing the longest match it can find, or a
literal byte if it can't find a match. Inversely, a much more elaborated
way of finding coding sequences of minimum size than the one currently
used by lzip could be developed, and the resulting sequence could also
be coded using the LZMA coding scheme.
Clzip currently implements two variants of the LZMA algorithm; fast
(used by option -0) and normal (used by all other compression levels).
@ -227,7 +227,7 @@ The format for running clzip is:
'--member-size=BYTES'
Set the member size limit to BYTES. A small member size may
degrade compression ratio, so use it only when needed. Valid values
range from 100 kB to 64 PiB. Defaults to 64 PiB.
range from 100 kB to 2 PiB. Defaults to 2 PiB.
'-c'
'--stdout'
@ -406,14 +406,12 @@ additional information before, between, or after them.
now.
'DS (coded dictionary size, 1 byte)'
Lzip divides the distance between any two powers of 2 into 8
equally spaced intervals, named "wedges". The dictionary size is
calculated by taking a power of 2 (the base size) and substracting
from it a number of wedges between 0 and 7. The size of a wedge is
(base_size / 16).
The dictionary size is calculated by taking a power of 2 (the base
size) and substracting from it a fraction between 0/16 and 7/16 of
the base size.
Bits 4-0 contain the base 2 logarithm of the base size (12 to 29).
Bits 7-5 contain the number of wedges (0 to 7) to substract from
the base size to obtain the dictionary size.
Bits 7-5 contain the numerator of the fraction (0 to 7) to
substract from the base size to obtain the dictionary size.
Example: 0xD3 = 2^19 - 6 * 2^15 = 512 KiB - 6 * 32 KiB = 320 KiB
Valid values for dictionary size range from 4 KiB to 512 MiB.
@ -547,13 +545,13 @@ Concept index

Tag Table:
Node: Top210
Node: Introduction903
Node: Algorithm6200
Node: Invoking clzip8963
Node: File format14514
Node: Examples17046
Node: Problems19015
Node: Concept index19541
Node: Introduction897
Node: Algorithm6100
Node: Invoking clzip8930
Node: File format14479
Node: Examples16881
Node: Problems18850
Node: Concept index19376

End Tag Table