[GRASS-SVN] r68422 - in grass-addons/grass7/imagery: . i.landsat8.qc
svn_grass at osgeo.org
svn_grass at osgeo.org
Wed May 11 03:16:37 PDT 2016
Author: sbl
Date: 2016-05-11 03:16:37 -0700 (Wed, 11 May 2016)
New Revision: 68422
Added:
grass-addons/grass7/imagery/i.landsat8.qc/
grass-addons/grass7/imagery/i.landsat8.qc/Makefile
grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.html
grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.py
Log:
i.landsat8.qc: added
Added: grass-addons/grass7/imagery/i.landsat8.qc/Makefile
===================================================================
--- grass-addons/grass7/imagery/i.landsat8.qc/Makefile (rev 0)
+++ grass-addons/grass7/imagery/i.landsat8.qc/Makefile 2016-05-11 10:16:37 UTC (rev 68422)
@@ -0,0 +1,7 @@
+MODULE_TOPDIR = ../..
+
+PGM = i.landsat8.qc
+
+include $(MODULE_TOPDIR)/include/Make/Script.make
+
+default: script
Property changes on: grass-addons/grass7/imagery/i.landsat8.qc/Makefile
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Added: svn:mime-type
+ text/x-makefile
Added: svn:eol-style
+ native
Added: grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.html
===================================================================
--- grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.html (rev 0)
+++ grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.html 2016-05-11 10:16:37 UTC (rev 68422)
@@ -0,0 +1,177 @@
+<h2>DESCRIPTION</h2>
+
+<p>Removing unreliable pixels is a fundamental and one of the first steps in
+remote sensing. Landsat8 provides a Quality Assessment (QA) band which can be
+used for this purpose.</p>
+
+<p>The <em>i.landsat8.qc</em> module filters (reclasifies) the QA band according
+to pixel quality characteristics the user defines as unacceptable.</p>
+
+<p>Values defined as unacceptable for a given condition will be set to NULL
+in the output raster map. All other values will be set to 1. The <em>i</em>-
+flag inverts this behavior.</p>
+
+<p>The Quality Assessment (QA) band from Landsat8 contains 16bit integer
+values that represent "bit-packed combinations of surface, atmosphere, and
+sensor conditions that can affect the overall usefulness of a given pixel".
+<br>
+The QA band is currently only available for Landsat 8 OLI/TIRS data.</p>
+
+<p>The following quality relevant conditions are represented as "single bits"
+in the Landsat8 QA band:</p>
+
+<table border="1" padding="0" spacing="1" style="width:300px;">
+ <tr>
+ <td>Condition</td>
+ <td>QA Bit Position</td>
+ </tr>
+ <tr>
+ <td>Designated Fill</td>
+ <td>0</td>
+ </tr>
+ <tr>
+ <td>Dropped Frame</td>
+ <td>1</td>
+ </tr>
+ <tr>
+ <td>Terrain Occlusion</td>
+ <td>2</td>
+ </tr>
+ <tr>
+ <td>Reserved (not currently used)</td>
+ <td>3</td>
+ </tr>
+</table>
+
+<p>Possible choices for the "single bits" are:</p>
+
+<table border="1" padding="0" spacing="1" style="width:300px;">
+ <tr>
+ <td>Value</td>
+ <td>Description</td>
+ <td>Bit representation</td>
+ </tr>
+ <tr>
+ <td>No</td>
+ <td>This condition does not exist</td>
+ <td>0</td>
+ </tr>
+ <tr>
+ <td>Yes</td>
+ <td>This condition exists</td>
+ <td>1</td>
+ </tr>
+</table>
+
+<p>The following quality relevant conditions are represented as "double bits"
+in the Landsat8 QA band:</p>
+
+<table>
+ <tr>
+ <td>QA Bit</td>
+ <td>Description Confidence</td>
+ </tr>
+ <tr>
+ <td>4-5</td>
+ <td>Water Confidence</td>
+ </tr>
+ <tr>
+ <td>6-7</td>
+ <td>Reserved (not currently used)</td>
+ </tr>
+ <tr>
+ <td>8-9</td>
+ <td>Vegetation Confidence</td>
+ </tr>
+ <tr>
+ <td>10-11</td>
+ <td>Snow/Ice Confidence</td>
+ </tr>
+ <tr>
+ <td>12-13</td>
+ <td>Cirrus Confidence</td>
+ </tr>
+ <tr>
+ <td>14-15</td>
+ <td>Cloud Confidence</td>
+ </tr>
+</table>
+
+<p>Possible choices for the "double bits" are:</p>
+
+<table border="1" padding="0" spacing="1" style="width:300px;">
+ <tr>
+ <td>Value</td>
+ <td>Description</td>
+ <td>Bit representation</td>
+ </tr>
+ <tr>
+ <td>Not Determined</td>
+ <td>Algorithm did not determine the status of this condition</td>
+ <td>00</td>
+ </tr>
+ <tr>
+ <td>No</td>
+ <td>Algorithm has low to no confidence that this condition exists
+ (0-33 percent confidence)</td>
+ <td>01</td>
+ </tr>
+ <tr>
+ <td>Maybe</td>
+ <td>Algorithm has medium confidence that this condition exists
+ (34-66 percent confidence)</td>
+ <td>10</td>
+ </tr>
+ <tr>
+ <td>Yes</td>
+ <td>Algorithm has high confidence that this condition exists
+ (67-100 percent confidence)</td>
+ <td>11</td>
+ </tr>
+</table>
+
+<h2>NOTES</h2>
+
+<p>The Landsat Quality Assessment band is an artificial band which represents
+an analysis based on <a href=https://landsat.usgs.gov/documents/LDCM_CVT_ADD.pdf>
+defined algorithms</a>. The USGS provides the users with the following note on
+how the QA band should be used:</p>
+
+<p>"Rigorous science applications seeking to optimize the value of pixels used
+in a study will find QA bits useful as a first level indicator of certain
+conditions. Otherwise, users are advised that this file contains information
+that can be easily misinterpreted and it is not recommended for general use."</p>
+
+<h2>EXAMPLE</h2>
+
+<div class="code"><pre>
+#Create a cloud mask:
+i.landsat8.qc --overwrite --verbose input=LC81980182015183LGN00_BQA \
+ cloud="Not Determined,Maybe,Yes" output=LC81980182015183LGN00_Cloud_Mask
+
+#Create a water mask:
+i.landsat8.qc --overwrite --verbose input=LC81980182015183LGN00_BQA \
+ water="Not Determined,Maybe,Yes" output=LC81980182015183LGN00_Water_Mask
+</pre></div>
+
+
+<h2>SEE ALSO</h2>
+
+<em>
+<a href="i.modis.qc.html">i.landsat8.swlst.html</a>,
+<a href="r.bitpattern.html">r.bitpattern.html</a>,
+<a href="i.landsat8.swlst.html">i.landsat8.swlst.html</a>,
+</em>
+
+<h2>REFERENCES</h2>
+
+<em><a href=http://landsat.usgs.gov/qualityband.php>http://landsat.usgs.gov/qualityband.php</a>
+<a href=https://landsat.usgs.gov/documents/LDCM_CVT_ADD.pdf>https://landsat.usgs.gov/documents/LDCM_CVT_ADD.pdf</a></em>
+
+<h2>AUTHOR</h2>
+
+<p>Stefan Blumentrath, Norwegian Institute for Nature Research, Oslo (Norway)</p>
+
+<p><i>Last changed: $Date$</i></p>
+
+
Property changes on: grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.html
___________________________________________________________________
Added: svn:mime-type
+ text/html
Added: svn:keywords
+ Author Date Id
Added: svn:eol-style
+ native
Added: grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.py
===================================================================
--- grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.py (rev 0)
+++ grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.py 2016-05-11 10:16:37 UTC (rev 68422)
@@ -0,0 +1,325 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+"""
+ MODULE: i.landsat8.qc
+
+ AUTHOR(S): Stefan Blumentrath <stefan.blumentrath at nina.no>
+
+ PURPOSE: Reclass Landsat8 QA band according to acceptable pixel quality
+ as defined by the user
+
+ COPYRIGHT: (C) 2016 by the GRASS Development Team
+
+ This program is free software under the GNU General Public
+ License (>=v2). Read the file COPYING that comes with GRASS
+ for details.
+"""
+
+#%Module
+#% description: Reclass Landsat8 QA band according to acceptable pixel quality as defined by the user
+#% keywords: imagery
+#% keywords: qc
+#% keywords: bitpattern
+#% keywords: mask
+#% keywords: landsat8
+#%End
+
+#%flag
+#% key: i
+#% description: Invert filter (default is set unacceptable pixels to NULL)
+#%end
+
+#%flag
+#% key: p
+#% guisection: Main
+#% description: Print effect of bitpattern filter in number of pixels filtered and exit
+#%end
+
+#%option G_OPT_R_INPUT
+#% guisection: Main
+#% description: Landsat8 QA band
+#% required : yes
+#%end
+
+#%option
+#% key: designated_fill
+#% multiple: No
+#% description: Unacceptable conditions for Designated Fill (bit 0)
+#% guisection: QA bit filter
+#% options: No, Yes
+#% required : no
+#%end
+
+#%option
+#% key: dropped_frame
+#% multiple: No
+#% description: Unacceptable conditions for Dropped Frame (bit 1)
+#% guisection: QA bit filter
+#% options: No, Yes
+#% required : no
+#%end
+
+#%option
+#% key: terrain_occlusion
+#% multiple: No
+#% description: Unacceptable conditions for Terrain Occlusion (bit 2)
+#% guisection: QA bit filter
+#% options: No, Yes
+#% required : no
+#%end
+
+##%option
+##% key: reserved
+##% multiple: No
+##% description: Unacceptable conditions for Reserved (not currently used) (bit 3)
+##% guisection: QA bit filter
+##% options: No, Yes
+##% required : no
+##%end
+
+#%option
+#% key: water
+#% multiple: yes
+#% description: Unacceptable conditions for Water Confidence (bit 4-5)
+#% guisection: QA bit filter
+#% options: Not Determined, No, Maybe, Yes
+#% required : no
+#%end
+
+#%option
+#% key: cloud_shaddow
+#% multiple: yes
+#% description: Unacceptable conditions for Cloud Shaddow Confidence (bit 6-7)
+#% guisection: QA bit filter
+#% options: Not Determined, No, Maybe, Yes
+#% required : no
+#%end
+
+#%option
+#% key: vegetation
+#% multiple: yes
+#% description: Unacceptable conditions for Vegetation Confidence (bit 8-9)
+#% guisection: QA bit filter
+#% options: Not Determined, No, Maybe, Yes
+#% required : no
+#%end
+
+#%option
+#% key: snow_ice
+#% multiple: yes
+#% description: Unacceptable conditions for Snow/Ice Confidence (bit 10-11)
+#% guisection: QA bit filter
+#% options: Not Determined, No, Maybe, Yes
+#% required : no
+#%end
+
+#%option
+#% key: cirrus
+#% multiple: yes
+#% description: Unacceptable conditions for Cirrus Confidence (bit 12-13)
+#% guisection: QA bit filter
+#% options: Not Determined, No, Maybe, Yes
+#% required : no
+#%end
+
+#%option
+#% key: cloud
+#% multiple: yes
+#% description: Unacceptable conditions for Cloud Confidence (bit 14-15)
+#% guisection: QA bit filter
+#% options: Not Determined, No, Maybe, Yes
+#% required : no
+#%end
+
+#%option G_OPT_R_OUTPUT
+#% description: Name for output QA band filter
+#% guisection: Main
+#% required: no
+#%end
+
+#%rules
+#% required: designated_fill,dropped_frame,terrain_occlusion,water,cloud_shaddow,vegetation,snow_ice,cirrus,cloud
+#%end
+
+import os
+import sys
+import grass.script as grass
+
+if "GISBASE" not in os.environ:
+ print "You must be in GRASS GIS to run this program."
+ sys.exit(1)
+
+
+def main():
+ """
+ Main program
+ """
+
+ # flags
+ invert = flags['i']
+ print_effect = flags['p']
+
+ # Parse options
+ input = options['input']
+ output = options['output']
+
+ # Define bitpattern filter (bf)
+ bf = {'designated_fill': options['designated_fill'],
+ 'dropped_frame': options['dropped_frame'],
+ 'terrain_occlusion': options['terrain_occlusion'],
+ # 'reserved': options[''],
+ 'water': options['water'],
+ 'cloud_shaddow': options['cloud_shaddow'],
+ 'vegetation': options['vegetation'],
+ 'snow_ice': options['snow_ice'],
+ 'cirrus': options['cirrus'],
+ 'cloud': options['cloud']}
+
+ # Check if propper input is provided:
+ if print_effect and output:
+ grass.fatal("output option and p-flag are mutually exclusive")
+
+ if print_effect and invert:
+ grass.fatal("i-flag and p-flag are mutually exclusive")
+
+ for o in ['water', 'cloud_shaddow', 'vegetation',
+ 'snow_ice', 'cirrus', 'cloud']:
+ if len(bf[o].split(',')) >= 4 and not invert:
+ grass.fatal("""All conditions for {} specified as
+ unacceptable, this will result in an empty map.""".format(o))
+ if not bf[o] and invert:
+ grass.fatal("""No conditions for {} selected for an
+ invers filter, this will result in an empty map.""".format(o))
+
+ # Define bitpattern characteristics according to
+ # http://landsat.usgs.gov/qualityband.php
+ """
+ Currently populated bits:
+
+ 0 Designated Fill
+ 1 Dropped Frame
+ 2 Terrain Occlusion
+ 3 Reserved (not currently used)
+ 4-5 Water Confidence
+ 6-7 Reserved for cloud shaddow
+ 8-9 Vegetation confidence
+ 10-11 Snow/Ice confidence
+ 12-13 Cirrus confidence
+ 14-15 Cloud confidence
+ """
+
+ # Define bit length (single or double bits)
+ bl = {'designated_fill': 1,
+ 'dropped_frame': 1,
+ 'terrain_occlusion': 1,
+ # 'reserved': 1,
+ 'water': 2,
+ 'cloud_shaddow': 2,
+ 'vegetation': 2,
+ 'snow_ice': 2,
+ 'cirrus': 2,
+ 'cloud': 2}
+
+ # Define bit position start
+ bps = {
+ 'designated_fill': 0,
+ 'dropped_frame': 1,
+ 'terrain_occlusion': 2,
+ # 'reserved': 3,
+ 'water': 4,
+ 'cloud_shaddow': 6,
+ 'vegetation': 8,
+ 'snow_ice': 10,
+ 'cirrus': 12,
+ 'cloud': 14}
+
+ """
+ For the single bits (0, 1, 2, and 3):
+ 0 = No, this condition does not exist
+ 1 = Yes, this condition exists.
+ """
+
+ # Define single bits dictionary
+ single_bits = {'No': '0',
+ 'Yes': '1'}
+
+ """
+The double bits (4-5, 6-7, 8-9, 10-11, 12-13, and 14-15), read from left to
+right, represent levels of confidence that a condition exists:
+00 = 'Not Determined' = Algorithm did not determine the status
+ of this condition
+01 = 'No' = Algorithm has low to no confidence that this condition exists
+ (0-33 percent confidence)
+10 = 'Maybe' = Algorithm has medium confidence that this condition exists
+ (34-66 percent confidence)
+11 = 'Yes' = Algorithm has high confidence that this condition exists
+ (67-100 percent confidence).
+ """
+
+ # Define double bits dictionary
+ double_bits = {'Not Determined': '00',
+ 'No': '01',
+ 'Maybe': '10',
+ 'Yes': '11'}
+
+ # Get categories and number of pixels from QA band raster
+ qa_cats = grass.parse_command('r.stats', flags='cn', input=input).keys()
+
+ # Initialise string for reclass rules
+ rc = ''
+
+ # Initialise dictionary for printing the effect of the different bitpattern
+ if print_effect:
+ pe = {}
+
+ # Loop over category values present in the QA band (qa_cats)
+ for line in qa_cats:
+ cat, pixels = line.split(' ')
+ # Convert integer categories into bitpattern
+ bin_cat = '{0:016b}'.format(int(cat))
+
+ # Loop over the bitpattern filter (bf) elements defined by the user
+ for k in bf.keys():
+ # Only work on bits included in the user`s bitpattern filter (bf)
+ if bf[k]:
+ # Calculate bit positions end (bpe)
+ bpe = bps[k] + bl[k]
+ # Extract unnacceptable bitpatterns (bp) form bitpattern filter
+ for bp in bf[k].split(','):
+ if bl[k] == 1:
+ bits = single_bits[bp]
+ else:
+ bits = double_bits[bp]
+ # Check if bitpattern of the category should be filtered
+ if bits == bin_cat[len(bin_cat) -
+ bpe:len(bin_cat) - bps[k]]:
+ # Add category to recassification rule
+ rc = rc + ' {}'.format(cat)
+ # Calculate nuber of pixels which are filtered using
+ # the current bitpattern
+ if print_effect:
+ pe_key = '{} = {}'.format(k, bp)
+ if pe_key not in pe.keys():
+ pe[pe_key] = int(pixels)
+ else:
+ pe[pe_key] = pe[pe_key] + int(pixels)
+
+ # Construct rules for reclassification
+ if invert:
+ rc = rc + ' = 1\n * = NULL'
+ else:
+ rc = rc + ' = NULL\n * = 1'
+
+ # Print filterstistics if requested, else reclassify
+ if print_effect:
+ for k in pe.keys():
+ sys.stdout.write('{} {}\n'.format(k, pe[k]))
+ else:
+ grass.write_command('r.reclass', flags='', input=input, output=output,
+ rules='-', stdin=rc)
+
+if __name__ == "__main__":
+ options, flags = grass.parser()
+ sys.exit(main())
+
Property changes on: grass-addons/grass7/imagery/i.landsat8.qc/i.landsat8.qc.py
___________________________________________________________________
Added: svn:executable
+ *
Added: svn:mime-type
+ text/x-python
Added: svn:eol-style
+ native
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