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20021023: converting GINI composite radar image values to dbZ

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  • Subject: 20021023: converting GINI composite radar image values to dbZ
  • Date: Wed, 23 Oct 2002 15:58:50 -0600
David,

I provide a calibration block in the image (in the unused portion 
of the GINI header) that is used to obtain the image calibration bar
values.

I created a section of code in $GEMPAK/source/gemlib/im/imgi2gm.f
with:
C
C*      Get calibration Block if it exists.
C*      Currently, only Unidata calibrations exist, using
C*          Word 47 = 128
C*      to signal that a calibration block is present.
C
At present the format is the number of calibration ranges N, followed by
N * 4 values where each set of 4 represents the pixel min, max and
data value min max they corespond to.

Recall that these are created from the Level 3 images which are already
sampled to a limited number of data ranges.

Steve Chiswell



>From: davidw <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200210232017.g9NKHAp23974

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>Hi,
>
> I'm working with the NEXRAD composite images that you generate in GINI for=
>mat.  Is there a method of converting the raw values to dBZ?  =
>
>
> Thanks for any info.
>
>
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><FONT SIZE=3D2><P>Hi,</P>
>
><P> I'm working with the NEXRAD composite images that you generate in GINI =
>format.  Is there a method of converting the raw values to dBZ?  </P>
>
><P> Thanks for any info.</P>
>
><P>&nbsp;</P></FONT></BODY>
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