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diff --git a/doc/clzip.info b/doc/clzip.info index 0942986..848adc2 100644 --- a/doc/clzip.info +++ b/doc/clzip.info @@ -11,7 +11,7 @@ File: clzip.info, Node: Top, Next: Introduction, Up: (dir) Clzip Manual ************ -This manual is for Clzip (version 1.6, 28 August 2014). +This manual is for Clzip (version 1.7-pre1, 26 February 2015). * Menu: @@ -24,7 +24,7 @@ This manual is for Clzip (version 1.6, 28 August 2014). * Concept index:: Index of concepts - Copyright (C) 2010-2014 Antonio Diaz Diaz. + Copyright (C) 2010-2015 Antonio Diaz Diaz. This manual is free documentation: you have unlimited permission to copy, distribute and modify it. @@ -36,9 +36,9 @@ 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 decompresses almost 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 +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". Clzip uses the lzip file format; the files produced by clzip are @@ -46,8 +46,9 @@ fully compatible with lzip-1.4 or newer, and can be rescued with lziprecover. Clzip is in fact a C language version of lzip, intended for embedded devices or systems lacking a C++ compiler. - The lzip file format is designed for long-term data archiving, taking -into account both data integrity and decoder availability: + The lzip file format is designed for data sharing and long-term +archiving, taking into account both data integrity and decoder +availability: * The lzip format provides very safe integrity checking and some data recovery means. The lziprecover program can repair bit-flip errors @@ -62,8 +63,8 @@ into account both data integrity and decoder availability: archaeologist to extract the data from a lzip file long after quantum computers eventually render LZMA obsolete. - * Additionally lzip is copylefted, which guarantees that it will - remain free forever. + * Additionally the lzip reference implementation is copylefted, which + guarantees that it will remain free forever. A nice feature of the lzip format is that a corrupt byte is easier to repair the nearer it is from the beginning of the file. Therefore, with @@ -90,6 +91,7 @@ tar or zutils. The amount of memory required for compression is about 1 or 2 times the dictionary size limit (1 if input file size is less than dictionary size limit, else 2) plus 9 times the dictionary size really used. The +option '-0' is special and only requires about 1.5 MiB at most. The amount of memory required for decompression is about 46 kB larger than the dictionary size really used. @@ -150,9 +152,8 @@ 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. - Lzip currently implements two variants of the LZMA algorithm; fast + Clzip currently implements two variants of the LZMA algorithm; fast (used by option -0) and normal (used by all other compression levels). -Clzip just implements the "normal" variant. The high compression of LZMA comes from combining two basic, well-proven compression ideas: sliding dictionaries (LZ77/78) and @@ -312,19 +313,19 @@ The format for running clzip is: verbosity level, showing status, compression ratio, dictionary size, and trailer contents (CRC, data size, member size). -'-1 .. -9' +'-0 .. -9' Set the compression parameters (dictionary size and match length limit) as shown in the table below. Note that '-9' can be much - slower than '-1'. These options have no effect when decompressing. + slower than '-0'. These options have no effect when decompressing. The bidimensional parameter space of LZMA can't be mapped to a linear scale optimal for all files. If your files are large, very repetitive, etc, you may need to use the '--match-length' and '--dictionary-size' options directly to achieve optimal - performance. For example, '-9m64' usually compresses executables - more (and faster) than '-9'. + performance. Level Dictionary size Match length limit + -0 64 KiB 16 bytes -1 1 MiB 5 bytes -2 1.5 MiB 6 bytes -3 2 MiB 8 bytes @@ -418,8 +419,8 @@ additional information before, between, or after them. 'Lzma stream' The lzma stream, finished by an end of stream marker. Uses default - values for encoder properties. See the lzip manual for a full - description. + values for encoder properties. *Note Stream format: (lzip)Stream + format, for a complete description. 'CRC32 (4 bytes)' CRC of the uncompressed original data. @@ -546,13 +547,13 @@ Concept index Tag Table: Node: Top210 -Node: Introduction896 -Node: Algorithm6095 -Node: Invoking clzip8901 -Node: File format14498 -Node: Examples17003 -Node: Problems18972 -Node: Concept index19498 +Node: Introduction903 +Node: Algorithm6200 +Node: Invoking clzip8963 +Node: File format14514 +Node: Examples17046 +Node: Problems19015 +Node: Concept index19541 End Tag Table |