TTCOMP
From Just Solve the File Format Problem
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'''TTComp archive''' is a compressed file format. It was apparently used by some software installation utilities. | '''TTComp archive''' is a compressed file format. It was apparently used by some software installation utilities. | ||
| − | It uses | + | It uses [[Shannon–Fano coding]] for data compression. It is probably identical, or nearly identical, to [[ZIP]]'s obsolete "IMPLODE" compression method. |
Though it may be called an "archive" format, it appears to store nothing more than a stream of compressed data. | Though it may be called an "archive" format, it appears to store nothing more than a stream of compressed data. | ||
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== Software == | == Software == | ||
* [http://www.exelana.com/techie/c/ttdecomp.html TTDecomp] | * [http://www.exelana.com/techie/c/ttdecomp.html TTDecomp] | ||
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Revision as of 15:29, 26 October 2014
TTComp archive is a compressed file format. It was apparently used by some software installation utilities.
It uses Shannon–Fano coding for data compression. It is probably identical, or nearly identical, to ZIP's obsolete "IMPLODE" compression method.
Though it may be called an "archive" format, it appears to store nothing more than a stream of compressed data.
Sample files
Identification
The first byte of a TTComp file indicates the type of compression:
-
0x00: binary compression -
0x01: ASCII compression
The second byte of a TTComp file specifies the size of the dictionary as follows:
-
0x04: 1024 bytes -
0x05: 2048 bytes -
0x06: 4096 bytes
Most TTComp files begin with bytes 0x00 0x06 indicating binary compression and a 4K dictionary.
