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[netCDFJava #LOE-612985]: Nexrad decoding errors


This information (courtesy of Michael James, our Gempak Guru) might be useful:

I think the nex2gini table calibration range is the information he is looking 


For example, 

N1P        30    4 
inches,0,9,-9999,-9999;10,100,0,0.5;101,200,0.5,5;201,255,5,12        TICZ99 

30 = unique product ID
4 = number of calibration ranges
inches = unit
; = delimiter for the 4 calibration ranges, containing min/mac for pixel value 
followed by min/max for the unit.

I think him finding the max value of 153 is the greatest pixel value available 
in that particular image. Most products use 256 levels, but N0R max possible 
value is 105.


> Ryan,
> Thanks for the Thredds link.  I have successfully downloaded and decoded some 
> of the GINI files; subsequently obtaining the PNG file and header 
> information.  However, I seem to be missing one bit of (important) 
> information.  I can't seem to find the index values within these PNGs.  For 
> example, in one of the DVL files, the index seems to range roughly from 
> 0-253.  In the N0R (reflectivity), I see index values in the PNG image go 
> from 0-80.  In the one hour precip (N1P), which I assume is in either mm or 
> inches, the max is 153.
> When performing an octal dump, I can see information pertaining to 'dBz' or 
> 'inches' (for n0r and n1p, respectively) around the 68th bit character, but I 
> can't make sense of where the magnitude values are found.  Do you have a 
> publication or a method that will help me extract the corresponding index 
> values to their associated dBz, inches, etc?   I have referenced the 
> following doc, but it describes nothing past octet 61.... 
> http://www.nws.noaa.gov/noaaport/document/ICD%20CH5-2005-1.pdf

Ticket Details
Ticket ID: LOE-612985
Department: Support netCDF Java
Priority: Normal
Status: Closed

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