19990104: using AA to subsect and AXFORM to dump (cont.)

>From: Scott Gennari <address@hidden>
>Organization: University of Hawaii
>Keywords: 199812282232.PAA01652 McIDAS AA AXFORM

Scott,

re: using AXFORM to get binary dump
>AXFORM seems to be what I need. I have yet one more question for you.
>
>AXFORM seems to dump the entire AREAFILE and what I need is
>a very small region (say 512x512) from the original AREA file which
>is say 5200x2700. Can I save a FRAME to an AREA file and then
>run AXFORM on the smaller AREA file?

>For example,
>
>IMGDISP 64 1 LATLON=20 155 (centers GOES-10 image of Big Island)
>MAKEIT 1 66 (fake command - dumps frame 1 to AREA file 66)
>AXFORM 66 ......

Yes, but the problem here is that you reduce the data to 8-bit in the
image display step.

>Is there an equivilent of my made up command "MAKEIT" command?

No, not in core McIDAS.

>Or is there another way just to run AXFORM on a subset of an AREA file?

What you need to do is use AA to subsect the file and then use AXFORM
to dump the smaller region.  For instance, here is an AA/AXFORM sequence
that will do the kind of thing that you are probably after:

AA 64 1234 0 EC 19:30 155:30 1 512 512
AXFORM 1234 OUTFILE FORMAT=I2 FTYPE=BIN UNIT=TEMP

AA does the subsecting while keeping the data in its original, 2-byte,
form.  You choose how to position the output sector; I chose Earth Centered.
You also choose the blowup/blowdown factor; I chose 1 so as to not muck
with the data.  Finally, you choose the size of the output in LINxELE
format.

Give this technique a try and see if it isn't what you are after.

>Otherwise when I run AXFORM, it dumps information for the entire
>AREA file and not just the region I'm interested in.

Right.

re: forgetting about binary output of AXFORM
>No problem at all, thanks for catching this!

Glad I didn't hold you up too long.

Tom

>From address@hidden  Mon Jan  4 13:55:50 1999

re: loading reduces resolution to 8-bit
>Argh. Thanks.

re: use AA to subsect and AXFORM to output
>Perfect! 
>Yup, works great.

>Thanks for all your help!
>Scott