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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."

7 of 648 comments (clear)

  1. Fractal image format by nmg196 · · Score: 5, Interesting

    I would have thought that rather than 'zipping' an existing image format to create a new one just to save 30%, they'd be better off improving the original image compression algorithm or coming up with a new one.

    Quite a while ago (years!) I had a program which could compress images into a fractal image format. It was amazing - the files were much smaller than JPEGs but looked a lot better. The only drawback was that it took ages to compress the images. But with the extra CPU horsepower we have today I'm surprised fractal image compression hasn't become more prevailant. It would still probably be useless for digital cameras though as it would probably be impossible to implement the compression in hardware/firmware such that it could compress a 6+ megapixel image within the requisit 1-2 seconds.

    Does anyone know what happened to fractal image format files (.fif) and why they never took off?

    1. Re:Fractal image format by mcbevin · · Score: 5, Informative

      Maybe, but StuffIt is an archival program. If I have 10gb of existing jpgs and want to archive them, then this is whats wanted. Reencoding them as you suggest would be equivalent to converting say an mp3 to ogg format - a surefire way to lose quality with little gain.

      Re fractal compression, people have been hyping it up for years but as far as I know it never really delivered. I'm dubious about any claims to some mysterious program which compresses anything amazingly well without strong evidence.

      Wavelet compression however is used in jpeg2000 which is a bit better than jpeg but even that isn't supported by any digital cameras.

      If StuffIt really does compress jpegs 25-30% that is a massive leap forward over the previous state-of-the-art compressors which reached I think around 3-4% - http://www.maximumcompression.com/data/jpg.php . Heres hoping their claims pan out, and that they release at least some details regarding the methods they used.

    2. Re:Fractal image format by ID10T5 · · Score: 5, Funny
      I'm not sure how practical 100% reduction is, but if anyone is interested I have an extremely fast algorithm for doing it.

      The results can be seen by the /. logo I have reduced here:

    3. Re:Fractal image format by happyhippy · · Score: 5, Insightful
      I did my final year project in Fractal Image Compression about 5 years ago.

      I concluded that it isnt practical for general use, it took too much time to compress an image (alright it was five years ago and so today it probably wouldnt matter), but most importantly there is no easy general compression solution for all images (for instance one that compresses tree pics well wont do faces well and vice versa).

      For a general dip into fractal image compression try to get and read 'Fractal Image Compression By Yuval Fisher'. Damn good read.

  2. What's the point? by CliffSpradlin · · Score: 5, Interesting

    The linked page shows average decompression times of 6-8 seconds for 600-800 KB files, rising with the size of the file. Who would benefit from this? It's obviously too slow to speed up web pages, and would be far too CPU intensive for consumer cameras. Professional photographers would have no use for this since they would use RAW images.

    I mean, it's cool and all to be able to compress JPGs by that much more, but the size gains are negated by the time it takes to decompress them. This seems just like those super high compression algorithms that have rather amazing compression rates, but take -forever- to compress or decompress, making them unusable. The difference is those are obviously and labeled as simply for scientific research into compression, but Aladdin seems to be trying to market this product for public consumption. The listed uses ( http://www.stuffit.com/imagecompression/ ) seem trivial at best.

    Who's gonna be buying this?

    -Cliff Spradlin

  3. Wow, that IS a breakthrough! by wcitechnologies · · Score: 5, Interesting

    I have a friend who's father is a professional photographer. He has gigabytes and gigabytes of images stored for his customers, should they want to order re-prints. They're thinking about setting up raid terabyte file server. I can certainyl say that this is good news for them!

    --
    Electrons are free; it is moving them that becomes expensive.
  4. Re:Questions by azuretongue · · Score: 5, Informative

    JPEG does not use Run-length encoding as its last compression step. Quote from the faq:"The JPEG spec defines two different "back end" modules for the final output of compressed data: either Huffman coding or arithmetic coding is allowed." http://www.faqs.org/faqs/jpeg-faq/part1/section-18 .html It goes on to say that arithmetic coding is ~10% smaller, but is patented, so don't use it. So what they are doing is removing the known chubby huffman coding and replacing it.