Re: "Standard" or "best" image format?

From: Steve Underwood (steveu@coppice.org)
Date: Sat May 13 2000 - 05:14:35 PDT

  • Next message: Stephen Williams: "Re: "Standard" or "best" image format?"

    pixel fairy wrote:

    > > the format to be
    > > portable so that it can be used by all software.
    > > Are there other
    > > considerations that I have neglected?
    >
    > tiff can save arbritary information in "tags" which
    > sometimes other programs cant read, for example a tiff
    > saved in photoshop has a pair that gimp cant read. but
    > this can save information like an ICC profile or gamma
    > information. png is probably the smallest portable
    > format, but the only thing it saves besides pixel data
    > is gamma. another advantage of tiff is the ability to
    > store more than one image in a file. an image viewer
    > can use this to read/write thumbnails and the like.
    >
    > gif is also a bad choice because of its limited color
    > depth (256 color pallet). if you want to avoid
    > proprietary nastiness make sure you dont save tiffs
    > with LZW compression. PNM is simply the easiest format
    > to read/write and probably the most portable since
    > images can be stored in plain text.
    >
    > overall, tif is the most flexible and should probably
    > be your default, with png for when you need smaller
    > file sizes.

    I don't think you really describe the full horror of TIFF incompatibility.
    Colour TIFF isn't as bad as the black and white form used for FAXes, but
    neither is great. Two graphics programs or FAX packages hardly ever read
    each other's files perfectly. LIBTIFF has quite poor tolerance to files
    that don't exactly fit the TIFF spec. - it usually core dumps. Its good at
    producing the right thing, though. Take care storing more than one image in
    a TIFF file, too. There are still a number of programs that cannot cope
    with that, particularly for FAX TIFF's where you might think multi-page
    files were most useful.

    I've nothing against the TIFF spec., although its a bit tag heavy. The
    problem is the majority of implementations suck big time.

    Steve 

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