Re: [OT] Re: getting pixel info from an image file

From: John Harrison (john_andronicus_at_hotmail.com)
Date: 05/08/04

  • Next message: John Harrison: "Re: accessing/overloading parent overloaded operators" 
    Date: 8 May 2004 07:26:37 GMT

    "cppaddict" <hello@hello.com> wrote in message
    news:j02p90p8jhlri6cv7a4f3hmnh0cshi5sj5@4ax.com...
    >
    > >
    > >It's not in the C++ standard library which has no graphics capabilities
    at
    > >all.
    > >
    > >I'm not aware of any free libraries that support this. The notorious
    patent
    > >that was claimed by Unisys over the GIF file format prevented the
    > >development of these. Even if you were to write your own code to do this
    you
    > >would be breaking the law unless you paid a royalty to Unisys. However
    that
    > >patent has now expired in the US although it remains in force in other
    parts
    > >of the world.
    > >
    > >Suggest you use PNG instead if possible.
    > >
    > >john
    > >
    >
    > John,
    >
    > Thanks. Two things:
    >
    > 1. Using PNG is fine. In fact, I can use any file format I want.
    > But where can I find a library/tutorial on how to do what I'm
    > describing?
    >
    > 2. You marked this post as OT. Where would be a better place to ask
    > this question?
    >
    > Thanks again,
    > cpp
    >

    Everything about PNG can be found here

    http://www.libpng.org/pub/png/libpng.html

    didn't see any tutorials but there are certainly manuals.

    There's a mailing list on the site above, that would be a good place for
    questions about PNG, alternatively you could try a newsgroup with graphics
    in its name, comp.graphics.algorithms perhaps (don't take that as a
    recommendation, I've never used that group).

    john

  • Next message: John Harrison: "Re: accessing/overloading parent overloaded operators"

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