http://fileformats.archiveteam.org/api.php?action=feedcontributions&feedformat=atom&user=Tdlewis77Just Solve the File Format Problem - User contributions [en]2026-04-18T03:20:18ZUser contributionsMediaWiki 1.19.2http://fileformats.archiveteam.org/wiki/TTCOMPTTCOMP2014-02-03T20:39:13Z<p>Tdlewis77: </p>
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<div>{{FormatInfo<br />
|formattype=electronic<br />
|subcat=Compression<br />
}}<br />
'''TTComp archive''' is a compressed file format. It was apparently used by some software installation utilities.<br />
<br />
It uses ''Shannon–Fano coding'' for data compression. It is probably identical, or nearly identical, to [[ZIP]]'s obsolete "IMPLODE" compression method.<br />
<br />
Though it may be called an "archive" format, it appears to store nothing more than a stream of compressed data.<br />
<br />
== Sample files ==<br />
* [http://ftp.serdica.org/public/drivers/Modems/BITWARE/VERSION.2/DOS/DISK1/BITFAX/ http://ftp.serdica.org/.../BITFAX/*.??$]<br />
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== Identification ==<br />
The first byte of a TTComp file indicates the type of compression:<br />
* <code>0x00</code>: binary compression<br />
* <code>0x01</code>: ASCII compression<br />
<br />
The second byte of a TTComp file specifies the size of the dictionary as follows:<br />
* <code>0x04</code>: 1024 bytes<br />
* <code>0x05</code>: 2048 bytes<br />
* <code>0x06</code>: 4096 bytes<br />
<br />
Most TTComp files begin with bytes <code>0x00 0x06</code> indicating binary compression and a 4K dictionary.<br />
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== Software ==<br />
* [http://www.exelana.com/techie/c/ttdecomp.html TTDecomp]<br />
<br />
== Links ==<br />
* [[Wikipedia:Shannon%E2%80%93Fano coding|Wikipedia: Shannon–Fano coding]]</div>Tdlewis77http://fileformats.archiveteam.org/wiki/TTCOMPTTCOMP2014-02-03T20:36:13Z<p>Tdlewis77: Documented identification bytes</p>
<hr />
<div>{{FormatInfo<br />
|formattype=electronic<br />
|subcat=Compression<br />
}}<br />
'''TTComp archive''' is a compressed file format. It was apparently used by some software installation utilities.<br />
<br />
It uses ''Shannon–Fano coding'' for data compression. It is probably identical, or nearly identical, to [[ZIP]]'s obsolete "IMPLODE" compression method.<br />
<br />
Though it may be called an "archive" format, it appears to store nothing more than a stream of compressed data.<br />
<br />
== Sample files ==<br />
* [http://ftp.serdica.org/public/drivers/Modems/BITWARE/VERSION.2/DOS/DISK1/BITFAX/ http://ftp.serdica.org/.../BITFAX/*.??$]<br />
<br />
== Identification ==<br />
The first byte of a TTComp file is either <code>0x00</code> or <code>0x01</code> and specifies whether to use fixed or variable size literal bytes.<br />
<br />
The second byte of a TTComp file specifies the size of the dictionary as follows:<br />
* <code>0x04</code>: 1024 bytes<br />
* <code>0x05</code>: 2048 bytes<br />
* <code>0x06</code>: 4096 bytes<br />
<br />
Most TTComp files begin with bytes <code>0x00 0x06</code>.<br />
<br />
== Software ==<br />
* [http://www.exelana.com/techie/c/ttdecomp.html TTDecomp]<br />
<br />
== Links ==<br />
* [[Wikipedia:Shannon%E2%80%93Fano coding|Wikipedia: Shannon–Fano coding]]</div>Tdlewis77