20001114: higher res topo file (cont.)

>From: Robert Mullenax <address@hidden>
>Organization:  Universal Weather and Aviation
>Keywords:  200011101719.eAAHJaD06220 McIDAS-X topography imagery

Robert,

>I fixed it.  Even though the USA30.info file says the data is big endian
>I decided to flip the bytes anyway, since the image looked like a "negative
>image"  I did FLIP=YES on the MAKEAREA command and it is fine now.

OK.  Without thinking about it, I did the MAKEAREA from a Solaris x86
system, and I did not set the FLIP=YES option.  Sorry...

>It is
>still strange though, as I would have thought the byte order would have been
>correct in the file for a non-Intel/DEC machine.

Me too.  Given the length of time that has passed since I first started
looking at the data, I can't say for sure that the file is not byte flipped.
Your test shows that it is byte flipped.

The easiest thing for me to do now is simply change the USA30.info file
to show that.  I have just done this, and I have changed the LAT and
LON values to indicate their non-signed values (e.g. -128 -> 128 W).

>Do you think it is the file or the MAKEAREA program?

I think that it is in the file.  I have used MAKEAREA for a number of
different images over the past 3.5 years, and I have never been left
with the impression that it was working "backwards".

>From address@hidden Tue Nov 14 08:12:32 2000

>Guess I'll have to play around with the enhancements, as even with EB I
>can't see any features in the eastern U.S.  especially along the Gulf
>Coast.  The area east of the Rockies is basically black except for the
>Appalchians.

I loaded the image as follows:

IMGDISP TOPO/HIRES MAG=-7 EU=IMAGE

and then ran EB.  You have to move the mouse cursor almost to the extreme
lower right hand side before you can see data values over, say, Florida.

I think I remember adding the scaling positionals to MAKEAREA to allow
one to focus in on/accentuate regions where the change in elevation
is slight.  This is what you will probably want to do for your high
resolution image over Texas.

>Thanks for the help!

Sorry to have not noticed that I did the original MAKEAREA on a little
endian system!

Tom

>From address@hidden Wed Nov 15 13:58:48 2000
>Subject: Re: 20001114: higher res topo file (cont.)

No problem Tom,

As always we(Universal and NSBF) appreciate the help very much!

-- 
Robert Mullenax
Assistant Weather Systems Administrator
Universal Weather and Aviation
8787 Tallyho
Houston, TX 77061
Phone: 713-944-1622 ext 2223
FAX: 713-943-4645
Email: address@hidden