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r.bitpattern

Compares bit patterns with a raster map.

r.bitpattern input=name output=name pattern=integer patval=integer [--overwrite] [--verbose] [--quiet] [--qq] [--ui]

Example:

r.bitpattern input=name output=name pattern=integer patval=integer

grass.script.run_command("r.bitpattern", input, output, pattern, patval, overwrite=False, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("r.bitpattern", input="name", output="name", pattern=integer, patval=integer)

Parameters

input=name [required]
    Name of input raster map
output=name [required]
    Name for output raster map
pattern=integer [required]
    Bit pattern position(s)
patval=integer [required]
    Bit pattern value
--overwrite
    Allow output files to overwrite existing files
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

input : str, required
    Name of input raster map
    Used as: input, raster, name
output : str, required
    Name for output raster map
    Used as: output, raster, name
pattern : int, required
    Bit pattern position(s)
patval : int, required
    Bit pattern value
overwrite: bool, optional
    Allow output files to overwrite existing files
    Default: False
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

r.bitpattern performs bit pattern comparisons. The module can be used to pixelwise verify a satellite image for low quality pixels if a Quality Control Bit Index map is provided (e.g. as for MODIS sensor maps). The functionality is two-fold:

  1. define position: set bit(s) to 1 which shall match, then convert this position pattern to integer, set pattern= parameter with that integer value
  2. define pattern *value* which should be in that position: first bit pattern of value, convert to integer, set patval= parameter

If several bitpatterns have to be tested, the resulting maps can be used to exclude low quality pixels in the input satellite image using r.mapcalc (OR and NOT operators).

EXAMPLE

  1. Define position:

        xx xx 1x xx
    binary: 1000 -> integer: 8 -> pattern=8

  2. Define value:

        Ex.: We want to check for 0 in that position
    xx xx 0x xx
    binary: 0000 -> integer: 0 -> patval=0
    If value can be arbitrary (0/1), then assume 0 value

SEE ALSO

i.modis.qc, r.mapcalc

AUTHORS

Radim Blazek, Markus Neteler

SOURCE CODE

Available at: r.bitpattern source code (history)
Latest change: Thursday Mar 20 21:36:57 2025 in commit 7286ecf