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Exhaustive Data Compressor Comparison

Posted by kdawson on from the pick-one-smaller-or-faster dept.

crazyeyes writes "This is easily the best article I've seen comparing data compression software. The author tests 11 compressors: 7-zip, ARJ32, bzip2, gzip, SBC Archiver, Squeez, StuffIt, WinAce, WinRAR, WinRK, and WinZip. All are tested using 8 filesets: audio (WAV and MP3), documents, e-books, movies (DivX and MPEG), and pictures (PSD and JPEG). He tests them at different settings and includes the aggregated results. Spoilers: WinRK gives the best compression but operates slowest; AJR32 is fastest but compresses least."

4 of 305 comments (clear)

  1. Screw speed, size reduction: gimme compatibility by xxxJonBoyxxx · · Score: 5, Insightful

    Screw speed and size reduction. All I want it compatibility with other OSs (i.e., fewest things that have to be installed on a base OS to use it). For that, I'd have to say Zip and/or gzip wins.

  2. Poor article. by FellowConspirator · · Score: 5, Insightful

    This is a poor article on several points. First, the entropy of the data in the files isn't quantified. Second, the strategy used for compression isn't described at all. If WinRK compresses so well on very high entropy data, there must be some filetype specific strategies used.

    Versions of the programs aren't given, nor the compile-time options (for the open source ones).

    Finally, Windows Vista isn't a suitable platform for conducting the tests. Most of these tools target WinXP in their current versions and changes to Vista introduced systematic differences in very basic things like memory usage, file I/O properties, etc.

    The idea of the article is fine, it's just that the analysis is half-baked.

    1. Re:Poor article. by RedWizzard · · Score: 5, Insightful
      I've got some more issues with the article. They didn't test filesystem compression. This would have been interesting to me because often the choice I make is not between different archivers, but between using an archiver or just compressing the directory with NTFS' native compression.

      They also focused on compression rate when I believe they should have focused on decompression rate. I'll probably only archive something once, but I may read from the archive dozens of times. What matters to me is the trade-off between space saved and extra time taken to read the data, not the one-off cost of compressing it.

  3. What's the point of compressing JPEG,MP3,DivX etc by mochan_s · · Score: 5, Insightful

    What's the point of compressing JPEG,MP3,DivX etc since they already do the compression? The streams are close to random (with max information) and all you could compress would be the headers between blocks in movies or the ID3 tag in MP3.