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Apple Patent Blocking PNG Development 357

Daniel writes: "Apple has a patent (U.S. Patent No. 5,379,129) on compositing a source and destination image using a mask image. This patent appears to read on alpha channel transparency, which the PNG and MNG file formats use. APPLE has declared in their patent statement to the Scalable Vector Graphics Working Group that their patent is only available for RAND Licensing. Since this patent appears to read on the PNG file format, Apple is hampering work on the PNG and MNG file formats. Perhaps Apple would like to clarify this situation by explicitly stating that this patent does not cover the PNG and MNG file formats or by RF Licensing their patent to the PNG and MNG development groups. Alternatively, the PNG and MNG developers are asking people to submit prior art in order to invalidate Apple's patent. SGI in particular appears to have prior art with their 'blendfunction.' Make sure the prior art you submit is older than May 08, 1992, the filing date of Apple's patent."
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Apple Patent Blocking PNG Development

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  • 1992? (Score:3, Interesting)

    by melquiades ( 314628 ) on Friday November 16, 2001 @02:05AM (#2573364) Homepage
    Apple introduced a function called "CopyDeepMask" into their API in ... I'm not sure ... certainly by System 7, maybe by 6. I'm pretty sure I was looking at that call in 1991, and maybe even 1990. Is 1992 the filing date, or the date they claim invention? Does it matter it pattent law?

    For some non-Apple prior art, when was the first version of Photoshop released? Alpha compositing is its bread and butter, and I'm pretty sure even the earliest versions let you turn an image into a selection.
    • Re:1992? (Score:2, Informative)

      by mosha ( 217365 )
      > I'm pretty sure I was looking at that call in 1991, and maybe even 1990. Is 1992 the filing date, or the date they claim invention

      The patent law allows one year since the date of public disclosure until the patent is filed. Therefore if you were looking at it in 1991 and they filed patent in 1992, they are still OK.
      • Re:1992? (Score:3, Insightful)

        by DrSpin ( 524593 )
        Don't worry, this was well known technology long before 1990.

        This patent is only good for toilet paper.

        Patents are granted by the patent office. They are not Valid until tested in a law court. It is not the patent office's job to determine whether there is prior art. If they know there is, then they will not grant the patent. If they are not certain then they will grant and wait for someone else to challenge (no sense in wasting taxpayer's money).

        As others have said, Apple have to maximise the shareholder value or the directors might go to jail. So even if they are certain that there is prior art, they will still file a patent - after all, it may be that no one bothers to challenge. Then, when it turns out Apple accidentally infringes some other, equally worthless, patent, they can do a mutual exchange. The shareholders will be impressed, and the potential for lawsuits reduced.

        This is considered sound business practice in the USA.

        It may be seen in a different light by the rest of the world, but WTF.

        • Apple have to maximize the shareholder value or the directors might go to jail

          Hahahahahhahah! So now, instead of putting directors and officers in jail for legitimate legal transgressions, environmental damage, collusion, union-busting, bribery, corruption and the like, which people have been demanding. Instead the slugs in the corporate offices hide behind SantaClaraCounty vs. Southern Pacific Railroad [], officer non-liability, and various other bits of ill-logic, but NOW you suggest that unless they push the moral bounds of the purpose of patents, that they rob from the community that empowers them, that unless they transgress against the public domain and the intellectual pursuits of a free community - that they WOULD GOTO JAIL!

          What a sad fucking statement that is. If that is true, which I accept, probably is; that if it is true, you Yankees need to do some serious re-thinking about the methods to which you organize your goddamned affairs.

          • So now, instead of putting directors and officers in jail for legitimate legal transgressions, environmental damage, collusion, union-busting, bribery, corruption and the like, which people have been demanding. Instead the slugs in the corporate offices hide behind SantaClaraCounty vs. Southern Pacific Railroad [], officer non-liability, and various other bits of ill-logic

            Corporate officers, directors, and employees are liable (civilly and criminally) for their own actions. They can be liable for the actions of subordinates if they knew about them or (rarely) if the they should have known about them.

            Corporate personhood is a limited legal doctrine which asserts that corporations have equal protection under the law and the right to due process of law. That's it.

            It has nothing to do with limitations on sharehold liability (which do exist) or non-existant limitations on the liability of corporate officers.

        • Patents are granted by the patent office. They are not Valid until tested in a law court. It is not the patent office's job to determine whether there is prior art.

          While I'm not questioning that this is how it works, I think it should not work this way. Going to court is expensive. And, more often than not in cases like this, it's having the better and higher paid lawyer that decides who wins, not being right. So the deck is immediately stacked against open standard development projects such as PNG. Unless they can enlist rich and powerful allies, they're hosed. Apple's got the muscle and the lawyers to force compliance because the mere threat of going to court, and the resultant expense and hassle, is a very big stick, even if Apple doesn't have a chance of winning the case.

          The civil law system we have in place right now is very easily used by bullies for bullying. And that sucks.


    • Xbitmaps using seperate mask and data were included in X11R3 (possibly earlier, but that is the first version I worked with.) XPM which combines the mask into a single file has been around since at least '89, but there are numerous earlier versions of the same thing used for blitter objects and sprites. Alpha masking I'm not sure about, but I'd look for something on antialiased mouse cursors or the like.
    • Re:1992? (Score:4, Interesting)

      by hearingaid ( 216439 ) <> on Friday November 16, 2001 @09:11AM (#2574039) Homepage

      1992 is the filing date.

      It no longer matters under U.S. law when they claim invention, under the new patent regime, which is since 1987 IIRC. (The U.S. in the eighties amended its patent and copyright laws to make them conformant to international standards.)

      As another poster pointed out, they're allowed public disclosure of the content of the patent for a year before their filing date. Any earlier disclosure and they themselves are prior art.

      However, for prior art from other companies or from private individuals, the day before the patent is filed is early enough to qualify as valid prior art. There was an interesting case with the patent on the Magic: the Gathering collectible card game, as TSR released a competitor to Magic about four days before the patent was filed. Hasbro now owns both companies, but I believe Steve Jackson Games was still able to use the TSR game as prior art to knock down the collectible card game patent.

      Yes, the U.S. Patent Office lets you patent the rules to games. No other patent office in the world does. There are worse things than software patents out there.

    • It probably predates even this. Apple had patents issued around the concepts of irregular regions, masks, and blitting algorithms as part of the original Lisa O/S. These were originally developed on the 6502 series of Apple machines in a package called AppleGraphics, which shipped in about 1980, I think.

      There's no sense in bitching them out about this. Their work very likely predates every other computer manufacturer except for work done at Xerox/PARC. And we all know that story...

  • by Bonker ( 243350 ) on Friday November 16, 2001 @02:08AM (#2573374)
    Now that I've finally weaned myself completely away from the GIF file format, PNG is having patent problems. Let's add another line to "Software Patents are bad, M'kay?"

    From what I understand, this patent tries to over-broadly apply to all in-file 'Alpha-channel' blending techniques.

    My suggestion is to create an open-patent free protocol that replaces one file transparency with two-file transparency. IE, one file is the base image, and the second file acts as a transparency mask. Since it uses two files, this technique should be free and clear of the Apple patent, right?

    An HTML tage for something like this would read something like

    < img src="file.jpg" mask="mask.jpg" >
  • by Tsar ( 536185 ) on Friday November 16, 2001 @02:08AM (#2573377) Homepage Journal
    You know how, when you type the last character that'll fit on the last line in a text window, the top line disappears, all the other lines move up one, and the cursor appears in the first position of a new blank line?

    IBM has a patent on that.
  • what if (Score:2, Insightful)

    by fishebulb ( 257214 )
    the hypocrisy around here getting irritating. Since it was apple doing it, they are asked to explain their actions. Anyone else (read microsoft) would do something like this, there would be outrage.
    • Re:what if (Score:2, Insightful)

      by fossa ( 212602 )

      There are like 20 comments at this point. It is clear there is no outrage. Why didn't I notice this earlier?

      I for one am extremely outraged. I'm sick of this shit. I'm sick of being pushed around by corps. Might makes right. It sickens me that I cannot in good faith buy from virtually any company. I don't want my money paying for this bullying. This ranting does nothing though. Apple's betting most people won't care and they're probably right. Heck how many people have the balls to even boycott RIAA member record companies? How many people have the balls to reject bullshit dvd's? Not that boycotting them makes any difference whatsoever. But how much of your money has gone toward buying politians? How much has gone toward bullying PNG? Some of the money is mine. It makes me sick. I buy this shit anymore. Even one of my favorite bands, the anti-establishment, anti-big record comany, anti-MTV NOFX, has a lead singer who started an RIAA member record company. How can I justify purchasing from them any longer? Thank you. I'll go back to my cave now.

      • Re:what if (Score:4, Insightful)

        by Graff ( 532189 ) on Friday November 16, 2001 @03:00AM (#2573496)

        Have you read this [] linked page? Have you read any statements made by Apple that they are using this patent to prevent you from using the PNG format?

        If you look at that page, you will see that Apple does offer a license for the patent as part of the SVG 1.0 patent which is being put together. It looks like they are just being cautious in order to keep their rights to the patent intact, but still allow it to be used for PNG and SVG.There are plenty of greedy corporations out there and Apple may in fact be one, but don't assume they are without looking at all the facts. Take a look at the sites listed in this article, write to Apple and ask questions, express your thoughts to Apple. If you are not then satisfied with what you see then you can make as much noise about it as you want. Making a big deal about this just because someone has implied wrongdoing on Apple's part is just being a follower.

  • "This patent appears to read on alpha channel transparency"

    So, is Apple going to go after the Photoshop or Gimp people ? that would really make them look like an ass ...

  • FUD? (Score:5, Insightful)

    by crayz ( 1056 ) on Friday November 16, 2001 @02:14AM (#2573398) Homepage
    Has Apple actually made any threats on this, or did someone just find this statement and see it as a possible precursor to a threat?

    PNG has been around for a while now, and Apple has never(AFAIK) said anything about it in the past. I really don't see how this changes anything.

    Now we're gonna get all these slashbots telling us how Apple is evil and everyone should boycott OS X/Darwin because of this, when they really haven't done anything. Chicken Little ought not be the standard tone of every Slashdot story.
    • Now we're gonna get all these slashbots telling us how Apple is evil

      No, but most patents are, especially ones with regards to software.

    • Re:FUD? (Score:3, Interesting)

      by Guy Smiley ( 9219 )
      Seems to be pure FUD, AFAICS. I'm on all of the PNG lists, and while there was a brief flurry of
      discussion about this at the same time the whole W3C RAND licensing issue was a big deal, there has
      not been anything since then (unless, of course I was unsubscribed from the PNG lists without my
      knowledge, hard to tell when you get a few hundred
      linux-kernel emails a day).

      In any case, no threats from Apple ever about PNG, just speculation and pre-emptive prior art
      gathering on the part of the PNG group.
    • Re:FUD? (Score:2, Insightful)

      by paulwomack ( 163598 )
      >> PNG has been around for a while now, and Apple has never(AFAIK) said anything about it in the past.

      Correct me if I'm wrong (hint: I don't think I am), but wouldn't that statement have applied to GIF/UNISYS?


    • by Per Abrahamsen ( 1397 ) on Friday November 16, 2001 @07:06AM (#2573828) Homepage
      Have we already forgot the GIF fiasco?

      It was well known that de-facto standard for file compression in the net, "compress", was covered by the Unisys compression patent. However, showed no interest in enforcing the patent outside hardware (modems and the like), and would informally tell people who asked that.

      Nonetheless the FSF insisted on having a patent free compression format for use by GNU, and eventually settled on gzip. This made some people angry, it was annoying to have to deal with a new compression format, and they claimed the FSF was seeing ghosts and that Unisys would never change their policy.

      However, as we all know, Unisys *did* change their policy, allthough the target wasn't compress (which meanwhile had lost most of its markedshare to gzip), but GIF which used the same algorithm internally, and had become a big thing thanks to the WWW. Thankfully, at that time we had gzip, and could create PNG fast using the same code.

      The morale "they haven't enforced the patent yet" provide false security. Companies don't enforce software patents until it become economically profitable to do so, typically when the algorithm is in so common use that it will be expensive to switch to an alternative. What we need is a legally binding promise not to enforce the patent.
      • They didn't look over "compress" because gzip had more market share. Relatively speaking, it didn't, since compress was still included in EVERY non-free unix distribution around, whether BSD or SYSV based. The problem was that compress was such a small, insignificant part of a Unix distribution that they couldn't get a dime out of it. The support of GIF and TIFF files, on the other hand, is a MAJOR component of most image processing programs, particularly after the web and how the early browsers had settled on GIF a sa standard.

        One must remember that the percentage of sales a patent is good for in royalities is directly related to how important the patented technology is to the application using the technology.

  • by Ryu2 ( 89645 ) on Friday November 16, 2001 @02:15AM (#2573400) Homepage Journal
    Try Porter and Duff []'s paper published in 1984 introducing image composition that started it all!!!!
    • You know the funny thing. Porter and Duff still work for Pixar and share the same CEO as Apple...

      I think the Porter/Duff paper is the last word on compositing.

    • by wray ( 59341 ) on Friday November 16, 2001 @04:20AM (#2573617)
      I posted this before as AC, but since it didn't get any points, I thought no one would see it, and I _do_ think it might help.

      Actually, Alvy Ray Smith with Ed Catmull created an alpha compositing system in 1978 while Ed Catmull was doing a paper for SIGGRAPH '78.

      He states this in his paper "Alpha and the History of Digital Compositing" in August 1995.

      He says that his earliest dated documentation he has for that code is dated January 13, 1978. He specifically showed compositing an alpha image on a background which should just be like another image. I hope this helps
      • Great! So now what? (Score:3, Interesting)

        by sterno ( 16320 )
        Now this leads to the ongoing quandry of patent law that nobody seems to have a good solution for. Let us assume for the moment that we have iron clad evidence of prior art, the only way to overturn the patent is a court challenge. Court challenges cost money.

        Big corporartions won't challenge a patent in court because there's a huge financial disincentive to do it. They could spend years in court and blow tons of money and still possibly lose. On the other hand, the patent holder will license the patent to them for a less exhorbitant sum. If Adobe had to pay to license PNG from Apple, they'd just pay the fee and pass the extra cost directly to the consumer and not bat an eye.

        The people who have the most to gain from challenging patents are small ISV's because they can hardly afford to be dumping limited resources into royalties. That problem is made even more complicated when you are talking about open source development. Of course they can neither afford royalty payments nor the court costs and time necessary to fight the patent. If a patent is going to expire in 4 or 5 years, why bother fighting because by the time you get through the courts it won't matter anymore.

        The end result of this is that innovation by small software vendors and open source developers is totally crippled by patents. Whether a patent is for a legitimate innovation or not is irrelevant to these groups because as soon as it gets approved and somebody demonstrates a willingness to enforce it, it becomes off limits to these groups.
    • Try Porter and Duff []'s paper published in 1984 introducing image composition that started it all!!!!
      So Apple was right in their big Superbowl commercial then. 1984 didn't turn out to be like 1984... or at least their version of it.

      The irony. :P

  • by spitzak ( 4019 ) on Friday November 16, 2001 @02:22AM (#2573424) Homepage
    I have a book printed in 1990 (Foley & van Dam Computer Graphics Principles and Practice, first edition), the references papers that talk about it.

    Every program that combines images and works with true color uses this. It is impossible not to, the algorithim is totally obvious. True color images (ie where the numbers represent levels of red, green, blue, rather than be indexes into a color pallette) were in common use in advanced visualization and simulations in 1980, such as Evans & Sutherland flight simulators. I also saw photo touch-up software that could duplicate a portion of the image and put it somewhere else in 1979, and I believe it must have used this, as otherwise the edges of the cut piece would be visible.

    PORT84, Porter, T., and T.Duff, "Compositing Digital Images," SIGGRAPH 84, 253-259.

    This is the paper most-often cited, however I think it's main addition is the enumeration of compositing operators and the introduction of "premultiplied" images. Before that I believe non-premultiplied was used as that was the more obvious solution. Also PNG does not use premulitplication.

    Even if Apple is going to be a pita about this, it does not affect PNG, as the file format itself does not do any compositing, it just stores a 4th "color" called the alpha. So I would not worry about it there. However Photoshop and Gimp and the in-house program I write for Digital Domain uses this, and about six thousand other pieces of commercial and free software.

    • by KFury ( 19522 ) on Friday November 16, 2001 @04:55AM (#2573659) Homepage
      "Even if Apple is going to be a pita about this, it does not affect PNG, as the file format itself does not do any compositing, it just stores a 4th "color" called the alpha. So I would not worry about it there."

      PNG isn't just a file format. It's an encoding and decoding mechanism. The encoding and decoding treat the alpha channel as an alpha channel, not a 'fourth color'.
      • Its a standard which covers a format structure which allows encoding and decoding mechanisms to act on it. It is not an encoding or decoding mechanism itself, but may or may not have requirements for those encoding and decoding mechanisms in order to be official called an PNG decoder. But its the mechanism itself that the patent would apply to. Just as its okay to have gif images, but its the mechanisms to which the compression patent would apply to that would cause the problem.

        If no one implemented alpha channels in PNG, it would not be an issue, even though PNG is capable of storing them, and it would look bad. Several other formats implement alpha channels, and so this does not apply to them directly either, only to the mechanisms which use it to do *compositing*.
      • Yeah, but the PNG libraries pass that 4th color along to the calling function. Only later, it's going to get applied when some program (i.e. a web browser) then uses this alpha channel data to merge the image with the background...

        So I don't think the PNG library authors are in any danger of breaking this patent. But if it's illegal for other programmers to then use the alpha transparency in their applications, it hurts the PNG group too.
    • Look at the reality.. the patent office doesn't
      give a DAMN about prior art! Free software
      development is going to be slowly strangled to
      death by software patents over the next 10 years.
      No patents on software! They don't work, they
      are supposed to encourage innovation but they
      just turn it into a legal quagmire. It's not like
      people are going to stop inventing new algorithms
      just because they can't get a patent on them. It's
      like saying nobody would invent new scientific theories if there was no nobel prize.
  • Well, I took a look at their patent, and it really seems like they did patent alpha-blending. Obviously they never should have been granted such an obvious patent.

    However, unless anyone has any evidence to the contrary, I'm going to assume that Apple only filed this as a defensive patent, and never intends to sue anyone because they make use of this idea.
  • GIF? (Score:2, Interesting)

    by Anonymous Coward
    GIF dates back to 1987 - whilst it doesn't have a full alpha channel, it does have a 1 bit alpha mask. Isn't that enough?

    I'm also pretty sure (but can't find evidence) that SGI's "Haeberli" image format dates back to the late 1980's - that format has a full alpha channel.

    I certainly designed hardware that would render textured polygons composited by alpha blends back in the late 1980's. I have screen shots taken from that system. []

    (Notice the alpha textured trees in the righthand image - those are 'composited via a mask').

    Earlier than that, the Quantel Paintbox (used in TV studio's to produce 2D artwork) had some kind of alpha-based compositing feature.

    This patent would have had to be filed in about 1978 to have avoided all prior art - and even then, it would have been considered 'trivial' IMHO.

  • by 90XDoubleSide ( 522791 ) <ninetyxdoubleside.hailmail@net> on Friday November 16, 2001 @02:35AM (#2573450)
    The patent statement was last updated in July, and in October Apple made a public statement that they would no longer support any patent agreement for web standards except royalty-free. Does anyone else see problems in the reporting here?

    Who honestly believes Apple would try to milk this almost certainly invalid patent? What do they gain by going after PNG? I think everyone will agree that web standards help Apple, and they are not going to do something against their best interest.

    And what is up with /. posting stories about months-old facts with no new developments anyways? I think it is good for /. to bring this issue up and get Apple to clarify their position, but listen to the report: "APPLE has declared in their patent statement to the Scalable Vector Graphics Working Group that their patent is only available for RAND Licensing." They make it sound like it just happened! And while I'm complaining, why is "Apple" in all caps ;)

  • by mj6798 ( 514047 ) on Friday November 16, 2001 @02:38AM (#2573454)
    Alpha compositing is in Foley and van Dam's second edition (1990, p835-840), and it is almost certainly also in the first edition, which I don't even have anymore. My guess is that people came up with this some time in the 1960's. Foley and van Dam even talk about subpixel issues and tree-based representations in compositing. Not that any of this shouldn't be obvious to any reasonably intelligent CS undegraduate anyway.

    I think this leaves only two possible conclusions: either Apple's legal staff and the inventors, Konstantin Othmer and Bruce Leak, are completely incompetent, or the inventors deliberately tried to patent a technique they knew to be in wide use and Apple's legal staff is deliberately trying to enforce an invalid patent. Apple didn't even have the smarts to offer this patent for "royalty free" licensing to SVG.

    Forget about any of Apple's claims of openness: this is such a clear case of patent abuse that it can't be an accident or mistake. The open source community would do well to stonewall Apple: don't incorporate OSX-related patches into open source projects, don't port to their hardware, and don't buy their products.

    • The technique doesn't date back to the 1960s. Alvy Ray Smith, who claims the technique's co-invention with Ed Catmull (who were both working at Lucasfilm at the time), says the earliest date on his alpha channel code is January 1978, but the technique was probably actually invented the previous December. (He has good reason for saying this, BTW. Final copy for Ed Catmull's 1978 SIGGRAPH paper was due in January, and the code in question was used to produce some of the figures.)

      Still well before 1992, of course.

      • That's a good reference. There may be other, earlier references, though: it's not unusual for the computer graphics community to reinvent techniques that were previously already known in the signal and image processing communities.
  • Before anyone goes off the deep end, I would like to know if Apple is intending on using this to block development on PNG, or if they are holding the patent but don't plan on interfering. Has there been a statement made by Apple that they are blocking the use of the PNG format or the SVG 1.0 patent?

    Holding a patent is one thing, vigorously going after people who use the patented technology is another. I'm not up on my legalese but I do see that Apple provides a RAND (Reasonable And Non-Discriminatory terms) license for the use of the technology. I'm not sure what the implications are, but it does look as if Apple is making an attempt to accommodate the SVG 1.0 patent.

    If people think that Apple's terms, or the terms of any of the 11 other patent holders involved, are too strict then I'd say your best bet is to write a nice letter to Apple explaining why you think so. Apple holds a lot of patents and, from what I've seen so far, are fairly reasonable about opening them up. Of course they still want to hold on to their intellectual property, but they have opened up patents in the past for reasonable use.
    • Apple holds a lot of patents and, from what I've seen so far, are fairly reasonable about opening them up. Of course they still want to hold on to their intellectual property, but they have opened up patents in the past for reasonable use.

      But it isn't their intellectual property: they applied for a patent on a 20 year old textbook technique. Apple is doing the equivalent of just taking land that belongs to the public. Letting a few pedestrians through every now and then doesn't make that "reasonable".

      There is only one reasonable thing to do for Apple: dedicate the patent to the public domain as quickly as possible.

  • by bjk4 ( 885 ) on Friday November 16, 2001 @02:52AM (#2573480) Homepage
    Patent 5,379,129 []

    CLick the "Image" button to see the lovely diagrams. There are a few items this patent does NOT cover, as explicitely mentioned in the text. This patent does not cover additional channel information, like alpha channels. It only covers a seperate, full color, mask image that is used to mask off the source image.

    I have a few questions:
    • The patent mentions that a black pixel codes for source image. Does this mean that if I decide the opposite, I can avoid royalties?
    • The patent mentions it uses full color mask images. Is a greyscale or black + white image considered a full color image?

    If the patent does not cover greyscale images, then not all sanity is lost!

  • Prior Art (Score:5, Informative)

    by corebreech ( 469871 ) on Friday November 16, 2001 @03:00AM (#2573495) Journal
    From the Second Edition of "Principles of Interactive Computer Graphics", by William M. Newman published by McGraw-Hill in 1979:

    We find on page 222 the pseudocode for the WriteColor procedure:

    procedure WriteColor(var ColorRaster: raster; x, y: integer);
    var i, j: integer;
    for j := ColorRaster.ymin to ColorRaster.ymax - 1 do
    for i := ColorRaster.xmin to ColorRaster.xmax - 1 do
    if GetPixel(ColorRaster, i, j) <> transparent then
    SetPixel(FrameBuffer, x+i, y+j, GetPixel(ColorRaster, i, j))

    And there was a First Edition published in 1973, for all I know it's in there too.

    BTW, there isn't anything Bill Atkinson did for Apple in QuickDraw that isn't spelled out in this book.
    • Re:Prior Art (Score:3, Informative)

      We find on page 222 the pseudocode for the WriteColor procedure:

      Ummmm, the algorithm that Apple patented is more complicated than that WriteColor procedure. WriteColor draws an image with _one_ level of transparency - i.e. each pixel is either completely transparent or completely opaque. Apple's algorithm is for how to draw an image where each pixel can be partially transparent - anywhere from 0 (totally transparent) to 255 (totally opaque).

      That's not to say that Apple's algorithm isn't completely obvious - and I'm sure there's prior art out there, but you'll have to look a little harder.

      BTW, there isn't anything Bill Atkinson did for Apple in QuickDraw that isn't spelled out in this book.

      How about making it really fast??? I'm still incredibly impressed with the amount of graphics power they got out of that original 8 MHz computer. Did you realize that even back in 1984, the Mac screen had rounded corners - and any drawing that took place on the screen was automatically clipped to those rounded corners? That's not exactly trivial to implement without a significant performance penalty.

      • Re:Prior Art (Score:2, Informative)

        by corebreech ( 469871 )
        Ummmm, the algorithm that Apple patented is more complicated than that WriteColor procedure.

        Ummmm, no. There are essentially two algorithms that Apple has patented here. The pseudocode given above applies to the first. RTFP.

        How about making it really fast??? ... Did you realize that even back in 1984, the Mac screen had rounded corners - and any drawing that took place on the screen was automatically clipped to those rounded corners?

        Get the book. It's called "Principles of Interactive Computer Graphics." It's published by McGraw-Hill. It tells you how to do this. Basically, Apple rechristened the rasterized-masking system talked about in the book as something called a Region (esp. RgnHandle.) It's really nothing more than a run-length-encoded bit mask.

        It lets you draw things with rounded corners really fast.
  • Alvy Ray Smith (Score:3, Informative)

    by Pseudonym ( 62607 ) on Friday November 16, 2001 @03:04AM (#2573504)

    The definitive reference on the history of alpha is Alvy Ray Smith's technical memo [] from 1995. It seems pretty clear that he co-invented the technique with Ed Catmull as a solution to a problem that Catmull was having with his sub-pixel hidden surface algorithm.

    The earliest dated documentation on his alpha channel code is January 13, 1978, although it was probably written the previous December. See footnote 4, page 6 of the memo for details.

  • If one even assumed this was true....

    So what, really? PNG was supposed to replace GIF because (Unisys?) was going to uphold patents on GIF, but... never happened because it all blew over.

    Has anyone even seen a PNG file online? I think I ran across a grand total of 1. Of course there could have been inline graphics that I didn't notice, but really?

    And IF Apple tried to enforce this, and PNG was widely used, what would they do? Get on Google and start at website 1 and go through 2,000,000 sequentially?

    Methinks that someone is blowing this out of proportion while misreading in the first place.
    • The web-stats package I use generates PNG as its output.

      Maybe you've heard of it: the webalizer.

      PNG is definitely out there; I would think of it as the third format behind GIF/JPEG.

    • I'm using PNGs if I can. No GIFs. PNGs are better, it's as simple as that.

      And, Unisys is bullying. You know, I thought I'd convert some of my PNGs to GIFs before people started complaining. But they went after the people writing convert, so I couldn't. But nobody has complained, so I don't care about GIFs.

    • "Has anyone even seen a PNG file online? I think I ran across a grand total of 1. Of course there could have been inline graphics that I didn't notice, but really?"

      Well, every image on our site is PNG (a couple of JPEGs, but whatever). We haven't, done't, and won't use GIF for the obvious reasons. I somehow doubt we're the only site using PGN graphics; you must not be online very much...

  • Apple's 10-K (Score:3, Interesting)

    by Dr. Awktagon ( 233360 ) on Friday November 16, 2001 @03:46AM (#2573561) Homepage

    I'm an Apple shareholder, and one fine day on the shitter I was reading their 10-K (annual SEC filing), and noticed this interesting quote on page 6 [], under "PATENTS, TRADEMARKS, COPYRIGHTS AND LICENSES":

    The Company currently holds rights to patents and copyrights relating to certain aspects of its computer systems, peripheral systems, and software. [...] Although the Company believes the ownership of such patents, copyrights, and trademarks is an important factor in its business and that its success does depend in part on the ownership thereof, the Company relies primarily on the innovative skills, technical competence, and marketing abilities of its personnel.

    I thought that was an interesting thing to write, I wonder what, say, Amazon or Microsoft say in their filings about patents?

    If anything comes of this patent (I doubt anything will, despite the sensationalist /. headline), you can use that in your letters to Apple or something.

  • I think it's worth pointing out, that Apple inherited compositing code from NeXT that deals with rather more than simply blending transparent colors.

    In the Cocoa framework, the NSImage compositing modes include:

    typedef enum _NSCompositingOperation {
    NSCompositeClear = 0,
    NSCompositeCopy = 1,
    NSCompositeSourceOver = 2,
    NSCompositeSourceIn = 3,
    NSCompositeSourceOut = 4,
    NSCompositeSourceAtop = 5,
    NSCompositeDestinationOver = 6,
    NSCompositeDestinationIn = 7,
    NSCompositeDestinationOut = 8,
    NSCompositeDestinationAtop = 9,
    NSCompositeXOR = 10,
    NSCompositePlusDarker = 11,
    NSCompositeHighlight = 12,
    NSCompositePlusLighter = 13
    } NSCompositingOperation;

    As you can see, that's more than color blending. I don't know if the PNG spec deals with more than one of these modes.

  • Commodore 64 sprites (Score:2, Informative)

    by kkovacs ( 80727 )
    Do you think the Commodore 64's sprite handling is prior enough? The idea was the same. And it was released MUCH before 1992.
  • ... software/hardware patents should be reconsidered. Maybe just a year would be enough? Maybe not even at all? The industry is wasting a lot of effort on trying to find out a way of doing things almost the same way as someone else, as to not hit any patents. This is way way stupid if you ask me.
  • by Sycraft-fu ( 314770 ) on Friday November 16, 2001 @05:42AM (#2573712)
    As other posters have mentioned:

    1) This is obvious.

    2) There is prior art.

    So even if Apple decided to try and enforce it, it'd get shot down however:

    3) Apple has already allowed royalty free use of this patent.

    Seriously folks, this story is just silly. Think for a moment how many things out there use multi level alpha transparency. All 3d cards from the Voodoo on do, Windows does in movie file formats and in the UI in XP, a bunch of X WMs do. If Apple tried to enforce this they'd have legal teams from all over after them, fact aside that they've already said they won't.

    Just because a company has a stupid patent doesn't mean they will try and enforce it.
  • by Paul Johnson ( 33553 ) on Friday November 16, 2001 @05:42AM (#2573713) Homepage
    Bear in mind that you can invalidate some claims but not others. So for example one of the claims is:

    7. A method as in claim 1 wherein said method produces anti-aliased text in said destination image by performing the method with the
    source image being a pattern and the mask image being anti-aliased text.

    (Claim 1 is the basic alpha-transparency concept).

    Suppose that someone comes up with prior art that invalidates claim 1. Apple can still claim rights over the use of this technique for anti-aliased text unless someone can show prior art which covers that specific application. So don't just look for prior descriptions of alpha-transparency: look for prior use of alpha transparency for text, and anything else in the claims.


  • I find this one (owned by Apple) hilarious too, granted November 13, 2001:

    System and method for analyzing web-server log files

    A method for analyzing traffic data generated by a plurality of web servers, which host a single web site. The site is mirrored on each server. A traffic data hit is generated responsive to each access of one of the servers. The hit includes data representing the time of the access. Each data hit is stored in a log file on the server accessed. The first-stored data hit is read from each server. Each of the read data hits are compared, and the oldest data hit is passed to a log file analyzer. The next-stored data hit is read from the server from which the passed data hit was read, and a second comparison is performed on the read data hits, with the oldest data hit being passed to the log file analyzer. This process continues until all of the data hits are read, compared, and passed to the log file analyzer. This results in passing all of the data hits to the log file analyzer in the chronological order in which the hits were generated.

  • by BitwizeGHC ( 145393 ) on Friday November 16, 2001 @08:07AM (#2573913) Homepage
    The patent only applies to triple alpha channels, i.e., where the alpha channel is itself an RGB value, and the source and destination images are blended channel by channel according to the RGB values in the triple alpha channel.

    It seems like an obvious extension of alpha blending (which was around for a while and is referenced in the patent) but that didn't stop Apple. HURR! WE R SMRT!
    • If that is the case, then there is prior art in the shading language of the RenderMan standard, which was first published in 1988. (RenderMan is a general 3d graphics api that pixar was pushing as a standard many years ago; now their renderer is also known as RenderMan.)

      Anyway, in the shading language, surface shaders set an output color and opacity, both as RGB. To generate the final image, these are then blended the obvious way, from the Porter and Duff paper that other people have referenced. Here is a link to PDF of the spec [], and here is a direct link to information about surface shaders [].

      Now, the amusing thing about all this is that the prior art here is from Pixar, which of course shares the same CEO as Apple...


  • How about using a bloody stencil to paint block letters on the side of a stupid truck?

    This is so irritating. Some obvious technique gets applied with computers, and all of a sudden some arrogant stuck up company gets a patent on it and starts throwing their weight around to stop open standard development. It makes me sick.

    Honestly, the day somebody gets a computer to pick their nose, a company's going to have a patent on it and try to make money off of it.


  • Why should any company have the law enforcement backed authority to shakedown individuals for cash for any concept or idea? Don't tell me the founding fathers of the US thought it was a good idea. All of them did not.

    Running around like squirrels looking for prior art whenever the specter of an intellectual monopoly threatens the free and open use of a key technology is missing the real point here.
  • This is a bit OT, but..

    In order for the USPTO to start being usefull again, why dont they use the public to gather prior art?

    Couldnt a website, shit even slashcode based, be set up that discloses patent applications (which are public-knowledge anyway) in order to allow the public to AID the EXAMINER in collecting prior art? Somewhere in the examination period should a 'peer-review' element be 'created' (or exercised) in this way.

    let the public see the patent application (disclose the applicant or not, its kinda irrelevant) and allow "all those reasonably versed in the art" to aid the Examiner. If the applicant disagrees with the examiner, let the APPLICANT take the isssue to court in order to SECURE his patent - dont allow the system to default in building a club to be held over the heads of others.

    I am not a supporter of "intellectual-property" in general, I see the free exchange of ideas in an open society of greater value to the community (than allowing ideas to be controlled by profit-seekers), but I digress, I think i might come to terms with the actions of the USPTO if they implemented a system such as this..

  • by Nindalf ( 526257 ) on Friday November 16, 2001 @11:47AM (#2574667)
    From the patent:
    Compositing can also be used to "blend" two images by controlling the degree to which the two images are merged or averaged. This is often done by a method called "alpha channel blending" in which an 8 bit alpha channel controls the blending of two 32 bit RGB images.

    However, while these methods have been useful, they are quite rigid and inflexible in accommodating images of various colors and bit depths[...]

    Alpha blending is directly contrasted to their method in the patent itself. This is no threat to the patent-free status of PNG or MNG.
  • Apple claims they wish to work together with the Open Source software community. I believe the PNG format came to be as an alternative to GIF, which is patent-encumbered. Since this was created to help out the Open Source (or Free, if you wish) community, I think Apple should try and work out a reasonable deal with the developers. I don't know what this deal should be. That's up to the parties involved.

    On the subject of software patents, I believe they should be allowed, although the patent office should closely scrutinize any such patents (as they should for any patents regardless), making sure that among other things, the invention is not a previously obvious solution to a problem (as originally intended), there is no prior art, and that the patent is extremely specific in its spirit and letter, so that a patent for any given technology will only affect people who are developing that specific technology and nothing else. The idea of patents is a good one. The problem is that the system is broken, and therefore, huge corporations abuse it.

    Oh well.

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