[McIDAS #TEU-219455]: topo map

Hi Kwan,

re:
> Thanks for making the comparison.  I will accept that the navigation
> transformation works fine.

Very good.

re:
> How about the color mapping problem?  Can you
> understand why the color map of new AREA file is different from that of the
> original?

Well, an pixel that is the result of a remap will, depending on the
output projection, be a combination of more than one pixel from
the original image, so they will be different.

So, the question is if IMGREMAP changes the range of brigntness values
in the output image.  To test this, I remapped a real-time WV image
(RTIMAGES/GE-WV) using the PRO=PS X 97 specification you used in
remapping your image (the result is a bit weird looking). My resulting
image looked like it had the same range of brightness as the input
both when using the IMAGE.EU (the default) and TOPO.EU enhancements
for colorization.

To explore further, I displayed your original image and remapped images
and colorized them using the TOPO.EU enhancement.  The results look consistent
to me -- I have attached snapshots of both for comparison.

Question:

- what are you using to display the images?

  I looked at the GIFs you attached previously, and the results do not look
  like McIDAS displays (but I could be wrong).
 
re:
> The IMGREMAP command does not seem to have an option to control
> the color resolution.

I agree, IMGREMAP does not seem to have any way to control the mapping
of the range of input values to output values.

Cheers,

Tom
--
****************************************************************************
Unidata User Support                                    UCAR Unidata Program
(303) 497-8642                                                 P.O. Box 3000
address@hidden                                   Boulder, CO 80307
----------------------------------------------------------------------------
Unidata HomePage                       http://www.unidata.ucar.edu
****************************************************************************


Ticket Details
===================
Ticket ID: TEU-219455
Department: Support McIDAS
Priority: Normal
Status: Closed

Attachment: kwan_topo_orig_topoet.gif
Description: GIF image

Attachment: kwan_topo_remap_topoet.gif
Description: GIF image