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On Wed, Mar 29, 2006 at 11:49:14PM -0800, Ethan A Merritt wrote:
> > Ick - TIFF is an evil, encumbered format. Use PNGs (which also use
> > more efficient and free lossless compression algorithms):
>
> I'm not sure what you're thinking of here.
>
> TIFF is a file format, not an image encoding scheme.
> Inside that TIFF file may be a raw RGB image, or a RLE
> (run length-encoded) image, or some proprietary compression format,
> or indeed a PNG image.
>
Exactly - which brings up compatibility problems. For example, TIFF
can use the png compression algorithm (as you mention), but some
programs won't read your TIFF anymore, including several web browsers,
since they won't recognize the tags.
> The thing that makes it TIFF, and the reason journals tend
> to request it, is that at the front of the file is a header
> section that contains envelope information like desired
> image size, resolution, enddian-ness, comments, and a whole
> slew of other things.
With no real standard for what can be there, how can it all be
supported, or how do you know anyone else will be able to read in all
your image tags?
> So it actually is more reasonable to request TIFF than a bare PNG
> file for this purpose, since the PNG standard doesn't even *have* a
> way of providing such envelope information.
If there is additional information you want to go along with the
image, use netCDF.
> There are some hackish work-arounds that stuff it
> into a comment records, but it is widely ignored, or interpreted
> idiosynchratically, by image display programs.
>
As it should. Its an image, not a dataset format.
Regards,
Tim
--
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Tim Fenn
[EMAIL PROTECTED]
Stanford University, School of Medicine
James H. Clark Center
318 Campus Drive, Room E300
Stanford, CA 94305-5432
Phone: (650) 736-1714
FAX: (650) 736-1961
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