[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: space products (fwd)




===============================================================================
Robb Kambic                                Unidata Program Center
Software Engineer III                      Univ. Corp for Atmospheric Research
address@hidden             WWW: http://www.unidata.ucar.edu/
===============================================================================

---------- Forwarded message ----------
Date: Fri, 17 Nov 2006 08:15:22 +0100
From: Simon Elliott <address@hidden>
To: Robb Kambic <address@hidden>
     John Caron <address@hidden>, Don Murray <address@hidden>,
     decoders <address@hidden>
Subject: Re: space products

Hello Robb,

HansPeter has asked me to contact you directly as I am responsible for
the generation of the GRIB2 data from EUMETSAT.  I am interested to read
about the extra characters you found inside hte message.  As I'm sure
you can imagine, we have exchanged the data with other centres using
different software and they have yet to spot this problem.

I suspect either (i) the GRIB data have been chopped up for
dissemination and not been properly re-assembled into the original
message, or (ii) at some stage the data have been transferred with ASCII
FTP ... this happens quite often.

If you could send me the file you mention, or make it availabel for FTP
transfer, I would be happy to investigate.

Regards,

Simon

Dr Simon Elliott
Product Implementation Manager
Operations Department
EUMETSAT
tel: (+49) 6151 807385
fax: (+49) 6151 807304


>>> Robb Kambic <address@hidden> 14/11/2006 22:50:35 >>>
HansPeter,

i investigated the problem with Grib2 decoder not being able to decode
the
space products, ie
MSG1-SEVI-MSGCLTH-0100-0100-20060102114500.000000000Z-12774_GRIB.grb

at first it seemed to be a table problem but that's not the case.
the products do not follow the standard Grib encoding, there are
extra characters inserted between the Grib format sections that's the
problem. i had the same problem with the Grib 1 format from some of
the
european centers. i tried the Grib 1 format fix then the decoder was
able to
decode the first 5 sections of the product but then the 6th section
didn't begin at the correct position. at this time, i could some help
in
finding out the format of the product, so i can modify the decoder. i
did a
quick look for the product information but was unable to get the
information
i needed. Could you contact the data provider to get the structure of
the
product?  or get a contact person for this product?

thanks,
robb...