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Breakthrough In JPEG Compression

Posted by timothy on from the like-free-flash-memory dept.

Kris_J writes "The makers of the (classic) compression package Stuffit have written a program that can compress JPGs by roughly 30%. This isn't the raw image to JPG compression, this is lossless compression applied to the JPG file. Typical compression rates for JPGs are 2% to -1%. If you read the whitepaper (PDF), they are even proposing a new image format; StuffIt Image Format (SIF). Now I just need someone to write a SIF compressor for my old Kodak DC260."

2 of 648 comments (clear)

  1. 30% saving for all that Pr0n! by hughk · · Score: 0, Redundant

    Just think if this was opened uup and could be quickly adopted by browsers. All that pr0n could be compressed by 30% giving us all a new lease of life on internet bandwidth.

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    See my journal, I write things there
  2. my guess... by mikecheng · · Score: 0, Redundant

    My guess is that they're expanding the compressed JPEG co-efficients (which are entropy encoded using huffman - sometimes using pre-calculated huffman tables - see the standard) and re-compressing them with an optimized algorithm - something proprietary and tweaked extensively for standard jpeg images.

    Sort of like saving space by converting gzip files to bzip2 files - except their compression scheme isn't documented or open.

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    Cool, but useless.