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[LDM #QZC-966326]: LMD bzip2 nexrad

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  • Subject: [LDM #QZC-966326]: LMD bzip2 nexrad
  • Date: Thu, 15 Jun 2017 16:44:07 -0600
Paul,

You need to skip 12 bytes before every message header to account for the legacy 
"CTM Header"; this information is hidden in section 7.6 of this document:

https://www.roc.noaa.gov/wsr88d/PublicDocs/ICDs/2620010E.pdf

In general though, I'd recommend looking at the NEXRAD Level 2 implementation 
in the MetPy package:

https://github.com/Unidata/MetPy/blob/master/metpy/io/nexrad.py

MetPy's NEXRAD level 2 (and level 3) support exhaustively covers the entire 
gamut of various message types. I'd be happy to help you install and use MetPy 
if that's of interest.

Ryan

> Hello,
> 
> I am trying to write a decode for the nexrad2 level 2 with the new LDM BZIP2 
> format.
> Attached is the python code to decompress the file and it seems to be working 
> - according
> to the byte counting.  However, the contents seem incorrect...that is the 
> first 16 bytes
> after the 24 byte header is strange as if the decompressed output is not of 
> the type byte
> or I have to do something to it to make it correct.  I have seen the output 
> of my decode
> for good (old) and bad (new) decodes.  I expected to see a 16 byte header 
> with msg size and
> msg type information and I get something in non-interpretable format (at 
> least to me).
> 
> Your advice is appreciated.

Ticket Details
===================
Ticket ID: QZC-966326
Department: Support Python
Priority: Normal
Status: Closed
===================
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