ACE (file format)
| ACE | |
|---|---|
| File extension : |
.ace
|
| MIME type : | application / x-ace-compressed |
| Developed by: | e-merge GmbH |
| Type: | Data compression |
| Website : | winace.com |
ACE is a file format for lossless data compression and archiving of files in electronic data processing. Compared to the ZIP file format, it is characterized by a higher degree of compression and, at the same time, a moderate compression speed.
Ace classic, similar Deflate , an LZ77 - Dictionary compressor with up to four megabytes of dictionary size in combination with entropy coding by Huffman used. From version 2, content-specific pre-filters for PCM audio files, raster graphic files and executable (Windows) program files can also be used.
The developer of the format sells a fee-based Windows program ( WinAce ) with which archives can be opened, created and modified. For the pure decompression process, the manufacturer offers a free decompressor in versions for DOS , macOS and Linux . Unpacking ACE archives is also supported by many other programs that can deal with several formats.
Since ACE is not a free or publicly documented file format like 7z and no reconstructions have been published, only precompiled implementations are available. There is an older free version (1.2) of the official command line extractor "unace", which has been released under the GPL by WinAce author Marcel Lemke . However, this cannot open any newer ACE archives (2.0 and higher). Apart from that, in contrast to other proprietary formats such as RAR , the decompression algorithm is not disclosed in the ACE format.
history
The ACE format was developed by Marcel Lemke and the rights to it were later bought by e-merge GmbH. It was introduced with WinAce, which has been released in developer versions since 1997 and version 1.0 appeared in July 1999. On July 7, 2000, version 2 of WinAce introduced a new file format with which content-specific pre-filters can be used. In the period from 1999 to 2001, the ACE format became increasingly popular with the WinAce packer, as the pack rates were often slightly higher than those of RAR. The format was mainly used for exchanging files and distributing so-called “releases” of black copies of various commercial products such as films, software and music via newsgroups and other platforms. In the end, however, there was a loss of importance, as the RAR format was improved from version 2.90 and since then has achieved higher compression rates in most cases.
ACE archives could also be unpacked with WinRAR. In 2019, a vulnerability was discovered that resulted in the removal of ACE support in WinRAR.
See also
Web links
Individual evidence
- ↑ a b winace.com
- ↑ Open ACE file extension. Retrieved December 26, 2013 .
- ↑ WinACE
- ↑ License information of the archiver ACE v1.1
- ↑ WinRAR download and support: What's new. Retrieved February 22, 2019 .
- ↑ heise online: Patch now! Attackers push backdoor through WinRAR holes. Retrieved February 26, 2019 .