[Gdal-dev] How to extract sub-image

[Clay, Bruce]

I know how to open a file and read the bands and thus the data so I can
get data for a sub-image but I don't see how to create a file of the
same format that is a particular sub-image of the overall image.
Actually this would be a subset of GTOPO30 data but I believe that is
treated the same as an actual image.

Since this seems to be a very common function, I was wondering if there
isn't already a tool written to do this.  That is a not Python tool.

The other thing I have been trying to do is to create a single geotiff
color image or sub-image from three separate geotiff images treating
each one as one of R, G or B as would be the case for creating a
composite color image from landsat data.  This function also seems like
it would already exist and I have asked before but I wanted to ask one
more time before I start writing one.  Again it needs to be a non-python
method to be able to build it into a larger program and because I don't
know python.  When I try to run the python scripts in the distribution I
get errors that I don't relate to.  I tried to use MicroDem to do this
but it created a grey scale image not a color one

Bruce Clay
bclay at ball.com