Add r.rgb algorithm

python/plugins/processing/algs/grass7/description/r.rgb.txt

@@ -0,0 +1,7 @@
+r.rgb
+Splits a raster map into red, green and blue maps.
+Raster (r.*)
+ParameterRaster|input|Name of input raster map|False
+OutputRaster|red|Red
+OutputRaster|green|Green
+OutputRaster|blue|Blue

python/plugins/processing/algs/grass7/ext/r_rgb.py

@@ -0,0 +1,95 @@
+# -*- coding: utf-8 -*-
+
+"""
+***************************************************************************
+    r_rgb.py
+    --------
+    Date                 : February 2016
+    Copyright            : (C) 2016 by Médéric Ribreux
+    Email                : medspx at medspx dot fr
+***************************************************************************
+*                                                                         *
+*   This program is free software; you can redistribute it and/or modify  *
+*   it under the terms of the GNU General Public License as published by  *
+*   the Free Software Foundation; either version 2 of the License, or     *
+*   (at your option) any later version.                                   *
+*                                                                         *
+***************************************************************************
+"""
+
+__author__ = 'Médéric Ribreux'
+__date__ = 'February 2016'
+__copyright__ = '(C) 2016, Médéric Ribreux'
+
+# This will get replaced with a git SHA1 when you do a git archive
+
+__revision__ = '$Format:%H$'
+
+
+def processInputs(alg):
+    # We need to import all the bands and color tables of the input raster
+    raster = alg.getParameterValue('input')
+    if raster in alg.exportedLayers.keys():
+        return
+
+    alg.setSessionProjectionFromLayer(raster, alg.commands)
+    destFilename = alg.getTempFilename()
+    alg.exportedLayers[raster] = destFilename
+    command = 'r.in.gdal input={} output={} --overwrite -o'.format(raster, destFilename)
+    alg.commands.append(command)
+
+    alg.setSessionProjectionFromProject(alg.commands)
+
+    region = unicode(alg.getParameterValue(alg.GRASS_REGION_EXTENT_PARAMETER))
+    regionCoords = region.split(',')
+    command = 'g.region'
+    command += ' -a'
+    command += ' n=' + unicode(regionCoords[3])
+    command += ' s=' + unicode(regionCoords[2])
+    command += ' e=' + unicode(regionCoords[1])
+    command += ' w=' + unicode(regionCoords[0])
+    cellsize = alg.getParameterValue(alg.GRASS_REGION_CELLSIZE_PARAMETER)
+    if cellsize:
+        command += ' res=' + unicode(cellsize)
+    else:
+        command += ' res=' + unicode(alg.getDefaultCellsize())
+    alignToResolution = alg.getParameterValue(alg.GRASS_REGION_ALIGN_TO_RESOLUTION)
+    if alignToResolution:
+        command += ' -a'
+    alg.commands.append(command)
+
+
+def processCommand(alg):
+    # We need to introduce something clever:
+    # if the input raster is multiband: export each component directly
+    raster = alg.exportedLayers[alg.getParameterValue('input')]
+    for color in ['red', 'green', 'blue']:
+        alg.exportedLayers[alg.getOutputValue(color)] = color + alg.uniqueSufix
+
+    commands = ["if [ $(g.list type=rast pattern='{}.*' | wc -l) -eq \"0\" ]; then".format(raster)]
+    commands.append("  r.rgb input={} red={} green={} blue={} --overwrite".format(
+        raster,
+        alg.exportedLayers[alg.getOutputValue('red')],
+        alg.exportedLayers[alg.getOutputValue('green')],
+        alg.exportedLayers[alg.getOutputValue('blue')]
+    ))
+    commands.append("fi")
+    alg.commands.extend(commands)
+
+
+def processOutputs(alg):
+    raster = alg.exportedLayers[alg.getParameterValue('input')]
+    commands = ["if [ $(g.list type=rast pattern='{}.*' | wc -l) -eq \"0\" ]; then".format(raster)]
+    for color in ['red', 'green', 'blue']:
+        commands.append("  r.out.gdal -t input={} output={} createopt=\"TFW=YES,COMPRESS=LZW\" --overwrite".format(
+            alg.exportedLayers[alg.getOutputValue(color)],
+            alg.getOutputValue(color)
+        ))
+    commands.append("else")
+    for color in ['red', 'green', 'blue']:
+        commands.append("  r.out.gdal -t input={} output={} createopt=\"TFW=YES,COMPRESS=LZW\" --overwrite".format(
+            '{}.{}'.format(raster, color),
+            alg.getOutputValue(color)
+        ))
+    commands.append("fi")
+    alg.commands.extend(commands)