Record Search Query: [Keyword='IDL']
Bit Mapper: Extracting and Visualizing Bit Flags from Byte Data
Entry ID: Bit_Mapper
Abstract: This IDL program extracts bit flags from byte data arrays, and
then plots them on a geolocated map with a user-defined color
scheme. The specific codes are designed to extract MOD06 L2 QA
bit flags and Cloud Mask (MOD06 or MOD35) bit flags, but can be
modified to extract and visualize other bit flags. The program
is separated into two codes, one which performs the extraction
... and one that visualizes the bit flags. The Extraction code
(included are codes to extract the MOD06 L2 QA flags and the
Cloud Mask (MOD06 or 35) flags) allows the user to extract the
bit flags from the specified granule, and output the flags to
individual SDSs inside a new HDF file. The visualization code
reads in the bit flag SDSs from this new HDF file, and plots
them on a geolocated map. The user can specify the color scheme
to use for bit flag values and which flags are to be plotted.
Individual or multiple granules can be plotted on a single
map. This code can be modified to extract and visualize bit
flags from other byte arrays.
Summary adapted from http://modis-atmos.gsfc.nasa.gov/tools_bitmapper.html)
Use Constraints Language and Environment Requirements: IDL.
Limitations: The code was tested using IDL version 5.2, more
recent versions of IDL have not been tested and results can not
Installation Tips: Once the files are unzipped and untarred,
examine the README.txt and PACKINGLIST text files for more
details on installing and running the code.
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Creation and Review Dates