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20000911: Unidata-Wisconsin (MCIDAS) images broadcast cessation 20000915

>From: Unidata User Support <address@hidden>
>Organization: Unidata Program Center
>Keywords: 200009112348.e8BNm5b26728 Unidata-Wisconsin image MCIDAS LWTOA3 


I am writing since I fear that you may have missed seeing the three
previous notifications (at the end of June and July, and beginning of
September) of the removal of delta-encoded satellite imagery from the
Unidata-Wisconsin (LDM feed type MCIDAS) datastream.

We have been broadcasting PNG compressed versions of the "regular" UW
stream images since the end of July.  This dual broadcast will cease at
18 Z this Friday, September 15.

*****                                                               *****
***** If you have not upgraded your ldm-mcidas decoders to the      *****
***** latest release, Version 7.6.4, you will stop decoding images  *****
***** at THIS FRIDAY!                                               *****
*****                                                               *****

1) Rationale for moving to PNG compression of imagery:

Delta-encoding is the compressed format that the images have been in
since the beginning of the Unidata-Wisconsin datastream.  Switching
to the much more efficient PNG compression will allow us to increase
the number of images in the Unidata-Wisconsin while mitigating the
impact that the increased data volume will have on your network.

2) What to do to continue using Unidata-Wisconsin imagery:

You must transition to use of the ldm-mcidas 7.6.4 decoder 'pnga2area'
in order to continue decoding imagery.

Binary distributions of ldm-mcidas are available from operating
system-specific directories of anonymous FTP on ftp.unidata.ucar.edu:

     Directory                     Operating system(s)
     pub/binary/osf1_4.0-alpha     DEC OSF/1 4.0
     pub/binary/hpux_11.00-hp9000  HP HP-UX 11.0
     pub/binary/aix_4.3-rs6000     IBM AIX 4.3
     pub/binary/linux_2.0-i586     RedHat 5.2 Linux
     pub/binary/linux_2.2-i686     RedHat 6.[12] Linux
     pub/binary/irix_6.5-mips      SGI Irix 6.5
     pub/binary/irix64_6.5-mips    SGI Irix64 6.5
     pub/binary/sunos_5.6-sparc    Sun Solaris SPARC Versions 2.6
     pub/binary/sunos_5.7-sparc    Sun Solaris SPARC Versions 2.7
     pub/binary/sunos_5.8-sparc    Sun Solaris SPARC Versions 2.8
     pub/binary/sunos_5.7-i86pc    Sun Solaris i86pc Versions 2.7
     pub/binary/sunos_5.8-i86pc    Sun Solaris i86pc Versions 2.8

A source distribution is also available in the pub/ldm-mcidas of
anonymous FTP on ftp.unidata.ucar.edu.  We are available to help you
build the decoders from source if your system is not compatible with
one of those listed above.

In all cases (source and binary), the distribution compressed tar file,
ldm-mcidas.tar.Z, should be FTPed in binary mode!

3) What else has to be done to transition to the new decoder:

Decoding the PNG compressed products will require that you install
and configure pqact.conf for the new ldm-mcidas decoder, pnga2area.

The ldm-mcidas distribution contains a file, ldm-mcidas-pqact.conf, of
example LDM pattern-actions for the PNG compressed imagery.  This file
also presents a short description of the product header format that
will eventually be used for all Unidata-Wisconsin imagery products.
Users should review the contents of ldm-mcidas-pqact.conf; extract and
adapt the actions to suit their environment (e.g., GEMPAK and/or
McIDAS); incorporate them into the pqact.conf file on their IDD ingest
machine; and send a HUP signal to pqact after verifying the entry with
'ldmadmin pqactcheck'.

4) What information is available about the new decoder, and how do
   I setup my LDM's pqact.conf file to run it:

Information on the PNG-compressed image decoder can be found in the
ldm-mcidas man pages under the ldm-mcidas Home Page:


Unidata User Support is available to help you in your transition.  If
you have any questions/difficulties/comments, PLEASE let us know ASAP.

Tom Yoksas