ARJZ

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(Created page with "{{FormatInfo |formattype=electronic |subcat=Archiving |extensions={{ext|arj}} |released=~1995 }} '''ARJZ''' is a compressed archive utility, primarily developed by Булат ...")
 
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== Format details ==
 
== Format details ==
ARJZ supports at least two new compression methods. Unfortunately, instead of inventing new compression method identifiers, it puts special values in the ''archiver version number'' field, and (at least when using the <code>-t9</code> option) the ''file type'' field.
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ARJZ's main features seem to be:
 
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* Increase ARJ's 26K history window to 32K, like [[LHA]]'s "lh6" method. Indicated by ARJ's ''minimum archiver version to extract'' field set to 50.
ARJZ compression is similar enough to ARJ that in some cases, especially for small files, it may be decompressible by standard ARJ software. But in general, it is incompatible.
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* Increase the history window to 64K, like LHA's "lh7" method. Indicated by ARJ's ''minimum archiver version to extract'' field set to 51.
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* Some sort of audio-targeted compression technique, enabled by the <code>-t9</code> option. Indicated by ARJ's "file type" field set to 9.
  
 
== Identification ==
 
== Identification ==
 
Like [[ARJ#Identification|ARJ]], an ARJZ file starts with bytes {{magic|0x60 0xea}}, and has <code>0x02</code> at offset 10.
 
Like [[ARJ#Identification|ARJ]], an ARJZ file starts with bytes {{magic|0x60 0xea}}, and has <code>0x02</code> at offset 10.
  
Unlike ARJ, an ARJZ file usually has <code>0x33</code> at offset 5 (meaning ''archiver version'' = 51). The documentation implies that this byte can also be <code>0x32</code>, but confirmation is needed.
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Unlike ARJ, ARJZ files are observed to have <code>0x33</code> at offset 5 (meaning ''archiver version'' = 51).
  
 
== Software ==
 
== Software ==
 
* [{{SACFTPURL|pack|arjz015.zip}} ARJZ 0.15 alpha] - Includes binaries for DOS, OS/2, and Windows NT console.
 
* [{{SACFTPURL|pack|arjz015.zip}} ARJZ 0.15 alpha] - Includes binaries for DOS, OS/2, and Windows NT console.
 
* [{{SACFTPURL|pack|unaz015.zip}} UNARJZ 0.15 beta]
 
* [{{SACFTPURL|pack|unaz015.zip}} UNARJZ 0.15 beta]

Revision as of 14:56, 20 June 2022

File Format
Name ARJZ
Ontology
Extension(s) .arj
Released ~1995

ARJZ is a compressed archive utility, primarily developed by Булат Зиганшин (Bulat Ziganshin, according to translation software). Its native file format is an incompatible variant of ARJ.

Format details

ARJZ's main features seem to be:

  • Increase ARJ's 26K history window to 32K, like LHA's "lh6" method. Indicated by ARJ's minimum archiver version to extract field set to 50.
  • Increase the history window to 64K, like LHA's "lh7" method. Indicated by ARJ's minimum archiver version to extract field set to 51.
  • Some sort of audio-targeted compression technique, enabled by the -t9 option. Indicated by ARJ's "file type" field set to 9.

Identification

Like ARJ, an ARJZ file starts with bytes 0x60 0xea, and has 0x02 at offset 10.

Unlike ARJ, ARJZ files are observed to have 0x33 at offset 5 (meaning archiver version = 51).

Software

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