| Versions tested: | 3, 3.1 |
| Rating: | 300 |
| Performance C/D: | 306/222 |
| Optimal parameters: | -m2 -d6 |
| Links: | csc-3.zip csc-3.src.zip csc-3.1.rar |
| Authors: | Fu Siyuan |
| Algorithms: | X86+LZ+ARI |
| Notable peformances: | Application2 |
About the program:author's description, email August 15, 2009
- LZ77 (1M -- 128M dictionary) + range coder
- Hash3+HC4 match finder + flexible parsing, some tricks added.
- E89transform by Shelwien. A simple 3-channel Delta on RGB or 4-channel Delta on WAV, not so good, but better than nothing. They are turned on automatically by file extension or manually.
- Three mode: -m1..-m3 from fast to high compression.
- typical speed: 2-5 M/s compression 15-40 M/s decompression (Single Core on 2.+ GHZ CPU)
Usage: csc3 [options] file1 file2
Options:
Default: -m2 -d4 (16M) Auto filter by extension.
- -m1 Fast -m2 Efficient -m3 Strong
- -d0 .. -d7 Dictionary Size:1M..128M (2^n)
- -fe Exe filter
- -fd# delta with #channels
- -fo Turn Off the filter. This parameter is recommended when compressing unknown extensions.
- -t DO NOT [write] OUTPUT (Maybe for test). file2 isn't necessary in such situation.
example: csc3 -m2 -d5 -fe e:\d\t\tar2 r:\out.csc
Authors description of the version 3.1:
This version is based on CSC 3. And I made some changes, mainly HashChain-4byte changed to HashChain-6byte. So it can find longer matches in less search cycles. And the coder now is using bit operation to handle bits with P=0.5 (like extra bits of match distance). So decompression is faster. I added a simple detector. It calcuate entropy of different channels of each small block. And use delta in some situation.email September 24, 2009However, the delta coding scheme is so bad so it works poor on audio/bmp, but better than nothing. E89 transforming also be used when necessary. The decompression process now checks the data, so it has less chance to crash without warning message.
The author submitted the following configurations in August 15, 2009.
-m1 -d2We use -d6 for -m3 instead due to the program running out of memory.
-m2 -d4
-m3 -d7
csc31 -m0 file1 file2
csc31 file1 file2 (default: -m2 -d4)
csc31 -d6 file1 file2
csc31 -m3 -d6 file file2
(Have info that should be added here? E-mail.)
We use custom compilation (MinGW 3.4 -O3, see the download link) for the version 3 due to the official executable crashing on the benchmark machine.
| Ver | Rating | CPR | DPR | S.E. | R.E. | Ratio | C. kB/s | D. kB/s | ||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| CompressionRatings.Com | ||||||||||||
| -m0 | ||||||||||||
| 3.1 | 181 | 204 | 56 | 1025 | 9 | 3.499 | 3081 | 16063 | ||||
| -m1 | ||||||||||||
| 3 | 63 | 71 | 20 | 648 | 1 | 3.248 | 2502 | 13305 | ||||
| 3.1 | 159 | +152% | +141% | +245% | +23% | +800% | 3.560 | +9.6% | 2148 | -14% | 16471 | +24% |
| -m2 -d4 | ||||||||||||
| 3 | 52 | 55 | 26 | 453 | 1 | 3.316 | 1522 | 13622 | ||||
| 3.1 | 124 | +138% | +131% | +212% | +24% | +700% | 3.607 | +8.8% | 1391 | -8.6% | 16706 | +23% |
| -m2 -d6 | ||||||||||||
| 3.1 | 300 | 306 | 222 | 713 | 52 | 3.951 | 1329 | 18151 | ||||
| -m3 -d6 | ||||||||||||
| 3 | 102 | 102 | 99 | 372 | 9 | 3.716 | 820 | 14925 | ||||
| 3.1 | 219 | +115% | +115% | +136% | +35% | +344% | 3.972 | +6.9% | 904 | +10% | 18196 | +22% |