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[filmscanners] Re: Archiving and when to sharpen (was:Color spaces for differentpurposes)



> yes; if there are many pixels of same color, image
> will compress more.

And that is almost never true for real-world photographs, although it is
certainly true quite often for computer-generated images such as diagrams
and the like.

> Wow, are you sure? The LZW TIFF was *larger*?

It can be if there is a _lot_ of detail.  In a lossless compression scheme,
the chances of a compressed image being _larger_ than the original are
always equal to the chances of it being smaller, if the image is completely
random.  In practice, totally random images are scarce, but the more detail
an image contains, the more closely it approaches randomness, and the
greater the probability that the compressed file may actually be larger than
the uncompressed file.

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