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A Look at Data Compression
With the new year fast approaching many of us look to the unenviable task of backing up last years data to make room for more of the same. That being said, rojakpot has taken a look at some of the data compression programs available and has a few insights that may help when looking for the best fit. From the article: "The best compressor of the aggregated fileset was, unsurprisingly, WinRK. It saved over 54MB more than its nearest competitor - Squeez. But both Squeez and SBC Archiver did very well, compared to the other compressors. The worst compressors were gzip and WinZip. Both compressors failed to save even 200MB of space in the aggregated results."
Seems to be a compression speed section on page 12 - Aggregated Results. Ranging from gzip really fast, to winrk really slow.
There are some amazing compression programs out there, trouble is they tend to take a while and consume lots of memory. PAQ gives some impressive results, but the latest benchmark figures are regularly improving. Let's not forget that compression is not good unless it is integrated into a usable tool. 7-zip seems to be the new archiver on the block at the moment. A closely related, but different, set of tools are the archivers, of which there are lots with many older formats still not supported by open source tools
They do it to sell more ad impressions. Each time you go to the next page you load a new ad.
I can't believe TFA made /. The only thing more defective than the benchmark data set (Hint: who cares how much a generic compressor can save on JPEGs?) is the absolutely hilarious part where the author just took "fastest" for each compressor and then tried to compare the compression. Indeed, StuffIt did what I consider the only sensible thing for "fastest" in an archiver, which is to just not even try to compress content that is unlikely to get significant savings. Oddly, the list for fastest compression is almost exactly the reverse of the list for best compression on every test. The "efficiency" is a metric that illuminates nothing. An ROC plot of rate vs compression for each test would have been a good idea; better would be to build ROC curves for each compressor, but I don't see that happening anytime soon.
I wouldn't try to draw any conclusions from this "study". Given the methodology, I wouldn't wait with bated breath for parts two and three of the study, where the author actually promises to try to set up the compressors for reasonable compression, either.
Ouch.
Since the original site seems to be really slow and split into a billion pages, those who aren't aware of it might want to look at MaximumCompression since it has tests for several file formats and also has a multiple file compression test that is sorted by efficiency. A program called SBC does the best, but the much more common WinRAR comes in a respectable third.
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It's a crime that the submitter didn't mention this was with the fastest compression settings.