20010321: convert GINI to AREA on-the-fly

>From: "Jason J. Levit" <address@hidden>
>Organization: Center for Analysis and Prediction of Storms/OU
>Keywords: 200103202045.f2KKjqL22810 NOAAPORT GINI

Jason,

>I checked out the McIDAS web site, and I found that the ADDE server
>documentation specifies that the ADDE server is just used to serve the
>GINI data for display in McIDAS-X?

The server gives read and list access to imagery in GINI format.  I did
not add the capability to output into GINI format, but I have been toying
with the idea of doing this.

>Perhaps I'm misunderstanding, but I
>can't find any documentation on how to use the ADDE server to convert
>NOAAPort GINI data to AREA format files.  Any suggestions?  Thanks!

The conversion process is implicit in McIDAS.  All one has to do is:

o create a dataset composed of GINI images; these will be listed/read
o create a dataset that will be composed of images in AREA format; this
  will be written to
o use IMGCOPY to copy from the input GINI dataset to the output AREA
  one

The conversion from one form to the other happens automatically and
transparently.  An example invocation of IMGCOPY that does the conversion
would be:

IMGCOPY RTGINI/GW4KIR MYDATA/IMAGES.1234 SIZE=ALL

In this example, the RTGINI dataset 'group' is composed of number of
'descriptors' like GW4KIR (GOES-West 4 km IR (10.7 um)).  RTGINI is the
full set; GW4KIR represents a subset.  All of the elements in the
subset must be in the same format (this is the only way that McIDAS
allows one to create subsets of groups).

The ADDE dataset MYDATA is a construct that we send out with all McIDAS
distributions.  It has a limited set of 'descriptor's:

MYDATA/IMAGES  <- images in McIDAS AREA format
MYDATA/GRIDS   <- grid files in McIDAS GRID format
MYDATA/PTSRCS  <- point source files in McIDAS MDXX format
MYDATA/TOPO    <- images in McIDAS AREA format

All dataset subsets, 'group/descriptor', will have zero or more
elements.  Those elements can be referenced directly with a 'position'
number:  'group/descriptor.position'.  A dataset can be defined so that
the 'position' number will be a value that is be intimately related to
a specific file.

In the example above, I am copying a GINI image from the RTGINI/GW4KIR
(since I have not specified which image to copy, the most recent one is
selected by default) set to a specific element ('position') in the
MYDATA/IMAGES set.  That position is the 1234th element in the set.

I define the MYDATA/IMAGES set to allow 9999 images in AREA file
format.  By doing so, there is a one-to-one mapping between
'dataset/group.position' and AREA file name:

MYDATA/IMAGES.1    <-> AREA0001
MYDATA/IMAGES.2    <-> AREA0002
 ...
MYDATA/IMAGES.1234 <-> AREA1234
 ...
MYDATA/IMAGES.9999 <-> AREA9999

So, using the above constructs, it is quite easy to convert any
particular GINI image into a specific AREA file.  Does this make
sense?

Tom