Re: ENVI ; My Question(s) [message #27103] |
Tue, 09 October 2001 22:05  |
Monchaya Piboon
Messages: 2 Registered: October 2001
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Junior Member |
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Hello all,
Thanks for replying me, Mark.
Here are my questions.
First, I'm using ENVI to analyze AVHRR images (HRPT format level 1b).
The images are downloaded from www.saa.noaa.gov . I need to do some
analysis over a small area (about 2x2 degree ), with specific latitude
and latitude.
(1) The website always yields images larger than your search area, so
I need to
find a way to narrow the image down to that specific area.
(2) The problem is I need to know how the pixels are corresponding
to latitude and
longitude values. When I read the header file using AVHRR utilities, the
header
showed correct 4 geographic corner values. But I could not find a way to
use those
values to correctly rectify the images.
(3) How do I georeference the images? Is there any way to
georeference, using only
geographic corner values? I don't have to get absolutely correct map
projections.
As long as I can estimate the average pixel values over that small area,
it's fine.
If you have any suggestions, please let me know.
Mon
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Monchaya ("Mon") Piboon
Graduate Student
Massachusetts Institute of Technology
Room 54-625
Cambridge MA 02139
Tel. (617) 253-1909
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