19990527: AREA file question

>From: Tye Parzybok <address@hidden>
>Organization: Oregon State University
>Keywords: 199905272219.QAA19503 McIDAS AREA

Tye,

>With the fuse burning on the project I am installing McIDAS
>for...I'm going to hold off on setting up the mcadde account
>for now.

OK.  This can be done at any time.

>After mulling through your excellent on-line support, I still
>can't seem to simply display a satellite image. The folks at
>U of Wash have provided me with an AREA file (*.are) of a 1-km
>GOES West satellite image but I can't get IMGLIST to see it.

Your parenthetical comment about the name of the file "(*.are)" is
the clue that I needed.  McIDAS requires that AREA file imagery
be in files named AREAnnnn ('nnnn' is a 4-digit number from 0001
to 9999).  If you have a file named something like 9905271259.are
then you need to do one of two things:

o rename it to AREA0001 (actually an name that follows the AREAnnnn
  naming convention)

o make a link between the file and a valid AREA file name:

  ln -s 9905271259.are AREA0001

>I am confused about the group/descriptor .postion arguments.

There is more to the story than you might guess.  The image data
servers provided by SSEC in McIDAS only understand imagery in
AREA file format that is named in the standard McIDAS manner (i.e.
AREAnnnn).  The group/descriptor convention is an abstraction that
lives on top of this naming convention.

Let's do a quick example.  First I will assume that the name of the
file that UW gave you is 9905271259.are.  Second, I will assume that
you put this file in the ~mcidas/workdata directory.  Third, I will
assume that you are running McIDAS as the user 'mcidas'.  Finally,
I will once again assume that the home directory for 'mcidas' is
/home/mcidas.

The first thing you need to do is to "rename" (as per examples above)
the file so that it follows the McIDAS naming convention:

cd /home/mcidas/workdata
ln -s 9905271259.are AREA0001

The next thing you need to do is tell McIDAS where it can find AREA0001.
There a couple of different ways of doing this, but the following is
the easiest.  From the McIDAS command line (in the text window) type:

REDIRECT ADD AREA0001 "/home/mcidas/workdata

You should now be able to ask McIDAS to verify that it sees AREA0001.

DMAP AREA0001

Now, you can setup an ADDE dataset that understands that AREA0001 is
a member.  I prefer to do this as follows:

DSSERVE ADD MYDATA/IMAGES AREA 1 9999 "All AREA files

This tells your McIDAS sessions that there is an ADDE group named MYDATA
that has a descriptor of IMAGES that is contained of AREA files that
are named AREA0001 - AREA9999, inclusive.  You can then list out the
AREA files in the MYDATA dataset by typing:

IMGLIST MYDATA/IMAGES.ALL

In the listing that results, you should see the information for the
image stored in AREA0001.

If the above has gone correctly, then you can display the image:

IMGDISP MYDATA/IMAGES.1 1

The MYDATA/IMAGES is the group/descriptor.  The '.1' is the dataset position
indicator.  The DSSERVE command above said that the dataset MYDATA with
descriptor IMAGES is populated by AREA files numbered 1 to 9999.  '.1'
refers to the first element of the data set which is '1'.

When you are successful, you can then play with the various keywords
for IMGDISP and refine your display:

IMGDISP MYDATA/IMAGES.1 LATLON=45 115 EU=IMAGE REFRESH='EG;MAP SAT 5 
COUNTY=ALL;MAP H 1'

etc.

>If this is easier to answer over the phone...let me know and
>I'll give you a call today or tomorrow (whenever it is best for
>you.)

If this didn't get you going, then try calling me tomorrow:
303-497-8642.

>A rookie Mcidas-user,

No problem.  McIDAS is tough to come up to speed on.  Once done, however,
it is a powerful tool in satellite image analysis.

Tom

>From address@hidden  Fri May 28 10:45:19 1999

>Tom,

>This e-mail helped me tremendously! I finally viewed my
>first satellite image in McIDAS and I feel like I am
>off an running. I have a lot more to learn, but your help
>has been greatly appreicated. Thank you again for your
>help.

>Have a good long weekend.

>-Tye