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April 2005

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2005.04.15 03:23 "TIFF Technote 3, draft 2", by Chris Cox
2005.04.15 08:06 "Re: TIFF Technote 3, draft 2", by Andrey Kiselev
2005.04.15 18:44 "Re: TIFF Technote 3, draft 2", by Chris Cox
2005.04.15 19:06 "Re: TIFF Technote 3, draft 2", by Bob Friesenhahn
2005.04.15 19:19 "Re: TIFF Technote 3, draft 2", by Chris Cox
2005.04.26 16:33 "Re: TIFF Technote 3, draft 2", by Kai-uwe Behrmann
2005.04.26 16:56 "Re: TIFF Technote 3, draft 2", by Bob Friesenhahn
2005.04.26 17:26 "Re: TIFF Technote 3, draft 2", by Kai-uwe Behrmann
2005.04.26 18:27 "Re: TIFF Technote 3, draft 2", by Chris Cox
2005.04.26 16:36 "Re: TIFF Technote 3, draft 2", by Kai-uwe Behrmann

2005.04.26 16:56 "Re: TIFF Technote 3, draft 2", by Bob Friesenhahn

> Most floating point data have some kind of reference to what 1.0 means, or
> simply expect the data representing some physical unit (cd/sqr meter or
> the like). The stonits tag make sense with unconverted XYZ data, while XYZ
> data are not covered directly by the current tiff spec. Alternatively the
> range description, suggestion by Bob, can be extended to add a physical
> value to the lower and upper 'normal' bounds.

The physical units often have no relationship to ideal default 
"viewing" parameters for a computer display.  For RGB data it is 
useful to know a recommended "black point" and "white point" for the 
image.  It is also useful to know the normal range of the data.  The 
image data is scaled for display so that values under the black point 
are "black" and values over the white point are "white".  This is of 
course only a crude approximation but it is better than nothing.

Bob
======================================
Bob Friesenhahn
bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/