[gdal-dev] Creating multi-band TIFF from a single band

[Gregor Mosheh]

Hey, all. What tool would I use for this; is this something more for 
libtiff or ImageMagick than for GDAL? I could do it pixel-by-pixel in 
Python Imaging Library or PHP+GD, but I have a feeling that it would be 
incredibly slow and that a faster way exists.

I have:
TIFF with data values encoded as pixel values, e.g. pixel value minus 20 
then times 10 equals feet elevation.

I want a set of TIFFs:

a) A TIFF with the values translated to true values, so the pixel value 
is true feet. It is my understanding that a TIFF can have 
signed-24-bit-float pixel values, which would be just peachy for both 
range and accuracy. (not all cases are as trivial as the one above)

b) Colorized TIFFs based on the numeric ranges in the true-value TIFF, 
using multiple prefab palettes. If I have to run multiple commands, one 
per palette, that's OK.

c) In both cases, retaining the georeferencing as these are for use in maps.

-- 
Gregor Mosheh / Greg Allensworth, BS, A+
System Administrator
HostGIS cartographic development & hosting services
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