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JPEG Patent Challenged

ChocLinux writes "The Public Patent Foundation has filed a request at the US Patent Office to revoke Compression Labs' data compression patent, which it is reportedly using to harrass anyone that implements the JPEG format. 'CLI's aggressive assertion of the '672 patent is causing substantial public harm by threatening this international standard on which the public relies,' says Pubpat in its filing."

26 of 278 comments (clear)

  1. Re:If JPGs aren't available... by blank89 · · Score: 1, Informative

    ...or png's.

  2. Re:Could it be? by Anonymous Coward · · Score: 2, Informative

    The problem with PNG is that it is much bigger than JPG for photographs. Many people are still using dialup to access the internet; PNG is too big.

  3. Covered at Groklaw by bstadil · · Score: 5, Informative

    This is covered in details over at Groklaw

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  4. Re:So what? by game+kid · · Score: 2, Informative
    I try to use PNGs for everything. Unlike JPEGs, PNGs can be lossless, meaning that they don't lose quality each time you save them. Internet Explorer, Mozilla, heck just about every web browser except lynx can display them just fine.

    As a small added bonus, PNG was the first W3C Recommendation (in 1996) (see the REC). It came well before their HTML 4.0 (1998). But I guess Slashdotters already knows such things... ;)

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  5. Re:So what? by Anonymous Coward · · Score: 1, Informative

    Actually you can use some javascript to get IE to render transparent PNGs "properly".
    e.g. http://homepage.ntlworld.com/bobosola/

  6. Re:Huffman? by Foobar+of+Borg · · Score: 2, Informative

    Um, you do realize that the patent was filed in October 1986 and granted in October 1987, don't you? I actually don't see what the big deal is anyway. The patent term is set to expire soon - October 2006 if they filed under the current system. I assume that they filed under the current system since, if the old system of 17 years after the granting of the patent were in place at the time of filing, the patent would have already expired over a year ago.

  7. Re:Potentially valid by tepples · · Score: 3, Informative

    If, and I say IF the patent is valid from a 'no prior art' and is not intuitively obvious

    That's one heck of an "if". It appears that PUBPAT has found prior art in a now-expired patent.

    If the patent is valid and the public has used it regardless, then they are within their rights (legal and quite likely moral) to defend it.

    Unless an alleged infringer can successfully make a laches defense.

  8. Patent terms under URAA by tepples · · Score: 3, Informative

    I assume that they filed under the current system since, if the old system of 17 years after the granting of the patent were in place at the time of filing, the patent would have already expired over a year ago.

    U.S. patents are issued with a term of grant + 3.5 years. Three renewals are available: grant + 7.5 years, grant + 11.5 years, and the full term. For this and other U.S. patents subsisting as of mid-1996, when the Uruguay Round Agreements Act came into effect in the United States, the full term is the longer of filing + 20 years or grant + 17 years.

  9. Re:Huffman? by sr180 · · Score: 2, Informative
    But where does this non-obvious? This is standard coding theory. You could use morse code as a prior example. The more common letters were given shorter codes and the least common letters given longer codes. For example: A = .- Z= --..

    This is simply standard coding theory of at least 30 years of age applied to images. The theory wasnt designed for specifically text, but ANY signal that was to be sent. This section of the patent describes nothing of merit.

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  10. Re:So what? by icydog · · Score: 3, Informative

    Conversion from truecolor to indexed PNG is lossy.

    And so is conversion from truecolor to 256-color BMP, and so, in fact, is cropping a BMP to include the middle 27.6% of the image. Is BMP lossy?

    Of course not. You can do things to any file to lose information, and reducing the number of colors in an image is obviously one of them. You can't say text files are lossy just because you can convert a Unicode text file to ASCII and lose some characters in the process.

    Then what Free format was designed to replace JPEG?

    I don't think there are any formats comparable to JPEG currently, and I know that there certainly aren't any in widespread use. That's the whole point of this article. If JPEG users get screwed, then we're in serious trouble. Think about how many photos on the web are in JPEG format, and how many photos on people's computers are JPEG.

  11. Re:Isn't this like what happened with GIFs? by Mycroft_VIII · · Score: 3, Informative

    Not exactly. In fact JPEG's and GIF's are targetted at two different kinds of images.
        Gifs (and later png's) work better for images with large areas of constant color (cartoon type images) where JPEG's are better for photgraphic like images where the the shifts in color are more gradual.
        Also JPEG is usually a lossy format (there is a lossless mode, but it's essentially a totally different form of compression) where as GIF and PNG are lossless.
        Using the wrong one can result in HUGE filesizes compared to using the right format for the job. Some apear to think a JPEG will always be a smaller final file because lossy should be smaller than lossless, but for drawings and cartoons this is often false. I've seen images (real images from real sources, not some 'ideal' image, or cherry picked image) that are much smaller in png than jpeg unless you turn the quality on the jpeg incoder so low that you can't tell horse from a house.

    Mycroft

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  12. Re:Patent law needs rethinking by tepples · · Score: 2, Informative

    Should be that if you don't enforce your patent within a reasonable time frame, you lose the right to do so.

    As I understand it, you do lose the right to some remedies. Heard of the laches defense? True, it's not as strict as the rule in trademark law, but having been trapped by a patent holder who has unfairly delayed taking any sort of legal action is still a recognized defense.

  13. Re:Could it be? by pingveno · · Score: 2, Informative

    I don't think PNG is necessarily "better" than JPEG. They're just for different purposes. JPEG is for lossy images, PNG is for lossless. Different requirements, different file formats.

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  14. Re:Could it be? by dacarr · · Score: 2, Informative

    Probably not, since PNG was a replacement for GIF. More likely, people would do the same thing, and develop a replacement format that is not entirely unlike JPEG.

    --
    This sig no verb.
  15. MPEG? by slashdotmsiriv · · Score: 2, Informative

    Forgive me if I am wrong, but I went through the patent: Motion compensation, intraframes etc... isn't it the MPEG format we are talking about? JPEG is the static picture encoding format that is based on the cosin transform. MPEG also uses cosign transform but many other techniques among which motion compensation DPCM etc.

  16. Was it obvious? by swthomas55 · · Score: 5, Informative
    While many software patents are "patently" invalid because of obvious prior art, this one was not obvious to me at the time. Although, I was working in a related field (computer graphics), and not directly in data compression. I had colleagues who were in signal processing (and DCT is at base a signal processing application), and none of them said "oh, that's obvious".

    If you read the pubpatent filing, their main point is that an earlier patent, issued to the same company, is prior art for all the points in the '672' patent. The earlier patent was filed more than a year (plus one month) prior to the filing of the '672' patent, which makes it legally prior art.

    Anyway, the sucker has less than a year to run, as it was filed in October, 1986. Probably why the lampreys at Forgent are pushing so aggressively. It'll only be a cash cow for another 11 months.

    Interestingly, I could have been a target of Unisys, except they couldn't have gotten much blood from this stone. I was the original author of the "compress" program, which turned into an early "open source" effort (although the term hadn't been invented at the time). Compress was an implementation of LZW, based on Welch's 1984 paper in Computer. Only later was I informed that it was patented. After it had been incorporated into Berkeley Unix releases and into the GIF format. I was happy when that patent finally expired, but I had absolutely no doubt of its legitimacy.

    As for the claimed superiority of PNG over JPEG, I'd say it depends on the application. JPEG was designed precisely and specifically for the purpose of compressing photographic images. Such images

    • Do not compress well using techniques like LZW and Huffman coding
    • Have intrinsic variation in pixel values due to noise in the recording process
    • Don't have precisely straight and sharp edges
    These characteristics make them poorly suited to lossless compression techniques, and also mean that a lossy technique will not degrade the image further than the original noisy recording method did. (Unless you turn up the loss level too high.)

    Because of the "if you have a hammer, every problem looks like a nail" principle, people have used JPEG in applications that it's not suited for -- applications where the lossy compression DOES degrade the image quality, and where a different method (LZW, for example) would in fact give a smaller file. Then other people point at these examples and say "PNG (or GIF) is better than JPEG!" My toolbox has hammers, screwdrivers, wrenches, etc. I try to pick the appropriate tool, and don't hammer with a wrench, for example. The same should be true of our computer tools.

  17. Re:Could it be? by jZnat · · Score: 4, Informative

    Or more to the point, fourier transforms are good for entropic data in general, but consequently end up distorting non-entropic data such as solid colours. Therefore, the next person to post a screenshot of a program in a JPEG image, especially one from MSPaint, is going to get stabbed repeatedly in the face.

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  18. Re:Could it be? by Bellum+Aeternus · · Score: 2, Informative

    FireFox supports PNG, and here's some IR behavior code for you CSS doc to make IE at least allow 32 bits (8x8x8x8) of data.

    <public:component>
    <public:attach event="onpropertychange" for="element" onEvent="propertyChanged()" />
    <script language="JavaScript">
        var needHack = needHack();
        var transparentImage = "/shared/graphics/spacer.gif";

        function propertyChanged() {
            if (event.propertyName == "src")
                pngHack();
        }

        function pngHack() {
            var src = "" + element.src;
            var png = /\.png$/i;

            if (needHack) {
                if (src.indexOf(transparentImage) != -1)
                    return; // Already fixed

                if (!png.test(src)) {
                    element.runtimeStyle.filter = "";
                } else {
                    element.src = transparentImage;
                    element.runtimeStyle.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoade r(src='" + src + "')";
                }
            }
        }

        function needHack() {
            var pos = navigator.userAgent.indexOf("MSIE ");

            if (pos == -1)    return false;

            var version = navigator.userAgent.substring(pos + 5);

            return (((version.indexOf("5.5") == 0) || (version.indexOf("6") == 0)) && (navigator.platform == ("Win32")));
        }

        pngHack();
    </script>
    </public:component>

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  19. What, you think it's a menu? by Grendel+Drago · · Score: 3, Informative

    Copyrights and patents aren't two names for the same thing. Inventions can be patented; the creative expression of an idea can be copyrighted. The idea itself cannot; see Feist v. Rural .

    --
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  20. Re:US Patents in the World by andy+jenkins · · Score: 3, Informative

    Think of all the Japanese digital camera manufacturers that sell cameras in the U.S.

  21. Re:Isn't this like what happened with GIFs? by TummyX · · Score: 1, Informative

    Um that's not really relevant since he was suggesting that JPEG could be replaced with free/open lossy format (not PNG).

  22. More info at Data Compression News Blog by schngrg · · Score: 4, Informative

    They have already been challaged by many, but for the first time someone has a concrete case with 'prior art'. You can read more on this at The Data Compression News Blog

    White Knight Charges Forgent http://www.c10n.info/archives/246

    [Disclaimer: Shameless self promotion]

  23. Re:US Patents in the World by Anonymous Coward · · Score: 1, Informative

    I think it's membership in the World Trade Organization (WTO) or the UN (Can't remember off the top my head) that says member organizations will respect each others laws regarding things like copyright and patents... so if you live in any major country, you should care since it applies to you....

  24. Not exactly by xant · · Score: 3, Informative

    PNG is lossless, so it looks good. JPEG is lossy, so it's small. You can get much better compression on photographic (lots of colors, few uniform color areas, few if any geometric features--this is only my crude layman's impression) images using lossy compression with JPEG, and furthermore, it's adjustable so if you need less quality, you can recover more bandwidth. PNG can only compress such images so far, and no farther.

    By contrast, PNG can represent alpha transparency, so (if your browser supports it.. hope IE7 is out soon) you can get neat effects with PNG. PNG is also great at presenting images, created with vector graphics, to software that doesn't do vector rendering. That means logos on web pages, line drawings of all sorts such as scientific plots, etc. But the reason it's good for such things is that such images benefit far more from lossless rendering (than photographs or 2d art or the like).

    PNG is great technology, but you can't simply put aside JPEG yet. Like PNG, JPEG is good at what it does, what it's intended for.

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    1. Re:Not exactly by zeke2.0 · · Score: 2, Informative

      Actually, the latest version allows for lossy compression via the mng spec, the succesor to png. I see your point though.

  25. Re:Isn't this like what happened with GIFs? by Mycroft_VIII · · Score: 2, Informative

    Actually that's not exactly correct, GIF can support more than 256 colors, it's just that using the fomat to do so requires a bit of 'finess'. That and the fact that for the longest time most programs didn't support creating >256 color images (why bother when most computers couldn't display them).
      If your currious about it, or want evidence the try these two links: http://phil.ipal.org/tc.html and http://en.wikipedia.org/wiki/GIF
        If you want to be pedantic about it ANY digitized image is lossy in the manner you speak of (though at about 21bits or so most of us can't tell with just our eyes), nature's bpp AND resolution is much higher than scanners and thus even at the bit-depth of high end scanners and digital cameras some data is lost. At some point (several usually) between the original light bouncing around and the stored image file you WILL lose data. Lossless generally means the data put into the compressor can be exactly reproduced by the compressor.

    Mycroft

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