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[IDD #VYN-104801]: please help a gempak user on weather ?

Hi Brian, Ed and Brandon,

Brian wrote:
> A weather.rsmas user wants to do something they used to do with Angel's
> metofis LDM setup, involving the GOES east and west images in a gempak
> format.

OK.  FYI: GEMPAK accepts/uses the same formats for satellite imagery
as McIDAS: AREA (e.g., Unidata-Wisconsin satellite image sectors in
the IDD UNIWISC (aka MCIDAS) datastream), and GINI (the format for the
image sectors in the IDD NIMAGE datastream).

> I set up unscrubbed folders on weather for these images in the current
> form at /data/ldm/UNSCRUBBED*

I will have to take a look to know exactly what you mean by this...

> Ed, Brandon, can you clarify for Tom what format is needed, or what
> command you want to work?
> Tom, can you help us find the right decoder?

Another FYI: GEMPAK and McIDAS can use the images from the UNIWISC and
NIMAGE datastreams in their unaltered forms (the UNIWISC images have
the actual image portion of the product compressed using PNG, and the
broadcast form of the images in the IDD NIMAGE datastream is a series
of zlib-compressed chunks.  If one wants to "decode" (really uncompress)
these images for possible use in something other than McIDAS, GEMPAK or
the IDV, then s/he would use an 'ldm-mcidas' decoder:  'pnga2area' for
UNIWISC imagery and 'zlibg2gini' for NIMAGE imagery.

> It might involve installing GEMPAK which we didn't do on weather, I think.
> I thought there were no more GEMPAK users at UM.

OK, this is not a big chore if needed.

> We will buy a new weather machine soon, but this seems worth bothering
> to set up if it can be ported to the new machine.

Very good.

Ed wrote:
> i see this as 2 issues.
> 1) populating the new ldm directories, and
> 2) getting my mcidas scripts ( imgremap.k etc )  to see that data.

OK.  Since you do not mention GEMPAK, I will assume that installation
of GEMPAK is off the table (for now; please let me know if I am wrong
in this assumption).

> 1) on the old metofis, data was here:
> /ldm/data/gempak/images/sat/GOES-1[2,3,4]/4km/IR/
> on the new weather, the directory structure only goes as far as:
> [eryan@weather ~]$ ls /data/ldm/gempak/images/

I seem to recall that we (Brian and I) made the decision that since
GEMPAK was not going to be used, the imagery REQUESTed by the 'ldm'
on weather would be processed by the LDM pattern-action file actions
that I provide in the Unidata McIDAS-X release.  If the desire is
to change the processing (FILEing or decoding using the appropriate
'ldm-mcidas' decoders referenced above), we can implement the GEMPAK
pattern-action file actions for processing the imagery data.  This
will require that the McIDAS ADDE setup be modified to know where
to look for the imagery (not a big deal at all, but something that
will need to be attended to).

> so
> a) the subsequent sub-directories have to be made,

The directory structure gets created by the LDM pattern-action
file actions used to process the imagery.  We just have to implement
the GEMPAK actions and turn off the McIDAS-X actions for the

> b) whatever turn on, so data flows into that directory, and

Yup, same as a).

> c) what ever needs to be turned on so it only keeps about
> 5-7 days of data in that directory ( scrub ? ).

Yup, the scouring that is done through crontab actions in the
'ldm' account will need to be adjusted to scour the GEMPAK
directory structure instead of the McIDAS directory structure.

> then,
> 2) on the new weather, if i do a ... i get ....
> dsserve.k LIST RTIMAGES
> ...
> RTIMAGES/GE-IR           IMAGE AREA                  GOES-East Hemispheric IR
> DIRFILE=/ldm/data/gempak/images/sat/GOES-1[23]/4km/IR/IR_*

Hmm, I do not recall setting up the ADDE dataset definitions (instantiated
in the ~mcidas/workdata/RESOLV.SRV definition file) to use /ldm/data as
the top level.  I could be mis-remembering, of course.

> but the new directory structure is "/data/ldm"  , not "/ldm/data",
> so how do i dsserve.k DEL  -or- ADD etc.


> or at least i think that is what the major issue is.

OK, here are the big questions that need to be answered before
anything is done:

1) is it your (Ed or anyone else) intention to use GEMPAK?

   I need to know if GEMPAK is to be installed.  If it is,
   then changing where the images are processed by the LDM
   should be changed to the GEMPAK way of doing things.  If
   not, then the layout on disk does not need to be changed,
   but McIDAS ADDE configurations need to be updated to
   point to the current locations.

2) does someone there know enough about McIDAS to reconfigure
   the ADDE dataset definitions?

   If not, no worries.  I can login and make the changes myself


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Ticket Details
Ticket ID: VYN-104801
Department: Support IDD
Priority: Normal
Status: Closed