Re: image formats - compression and loading

[mooney@aps.anl.gov (Tim Mooney)]

Peregrine writes...
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> Here's a draft of a wish list -- comments welcome!
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> 1. Lossless, 16-bit grey (We won't have more than 16-bits ever, will we?)
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Ok, I realize this is heresy and I expect to get torched for it, but is
it really essential that compression of scientific data be absolutely
lossless in order that the information contained in that data be
preserved without loss?  For example, if you know that statistical
errors in your data are larger than some quantity 'e', can't you
randomly diddle numbers by less than 'e' without losing information?

Another example: In many cases, we use 32-bit numbers systematically
because we need a large dynamic range, but we never have 32-bit
precision, and so we could usually drop eight, or even 16, bits if only
we didn't introduce any statistically significant artifacts in the process.

Tim Mooney