TTCOMP is the informal name of a file compression utility developed by SWFTE International. Its compressed file format is just a raw blob of PKWARE DCL Implode-compressed data. The name "TTCOMP" has sometimes been used (misused?) for any file compressed in such a manner, even if it has nothing to do with the TTCOMP software.
The software is included in SWFTE's Typecase product, and maybe some other SWFTE products, as files named "COMPR.EXE" and "DECOMPR.EXE". It may also found by itself, as files named "TTCOMP.EXE" and "TTDECOMP.EXE", though there's no evidence that this is an official distribution. The origin of the name "TTCOMP" is unknown; Typecase does not appear to use it. Someone may have derived it from the .TTC filename extension that Typecase uses for compressed TrueType fonts.
Refer to PKWARE DCL Implode#Identification for how to identify PKWARE DCL Implode format in general.
TTCOMP.EXE/COMPR.EXE appears to only ever use binary compression, and a 4K dictionary. But TTDECOMP.EXE/DECOMPR.EXE can decompress all six modes. So you could decide that true TTCOMP files always start with bytes
0x00 0x06, or you could account for the other modes as well.
Also be aware of ZAR (Zip-Archiv) format, which can be mistaken for TTCOMP.
- ttcomp.zip → TTCOMP.EXE, TTDECOMP.EXE (DOS software)
- Typecase v2.60 (at Vetusware) (Windows 3.x software; compression utilities are for DOS)
See also PKWARE DCL Implode#Software.
- Typecase Demo → *.TTC
- Universal Dial UP Modem Driver CD → SOFTWARE/BITWARE/.../*.??$