# -*- coding: utf-8 -*- """ *************************************************************************** ZonalStatistics.py --------------------- Date : September 2016 Copyright : (C) 2016 by Alexander Bruy Email : alexander dot bruy at gmail dot com *************************************************************************** * * * 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__ = 'Alexander Bruy' __date__ = 'September 2016' __copyright__ = '(C) 2016, Alexander Bruy' import os from collections import OrderedDict from qgis.PyQt.QtGui import QIcon from qgis.analysis import QgsZonalStatistics from qgis.core import (QgsProcessing, QgsProcessingAlgorithm, QgsProcessingParameterVectorLayer, QgsProcessingParameterRasterLayer, QgsProcessingParameterString, QgsProcessingParameterBand, QgsProcessingParameterEnum, QgsProcessingOutputVectorLayer) from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm pluginPath = os.path.split(os.path.split(os.path.dirname(__file__))[0])[0] class ZonalStatistics(QgisAlgorithm): INPUT_RASTER = 'INPUT_RASTER' RASTER_BAND = 'RASTER_BAND' INPUT_VECTOR = 'INPUT_VECTOR' COLUMN_PREFIX = 'COLUMN_PREFIX' STATISTICS = 'STATS' def icon(self): return QIcon(os.path.join(pluginPath, 'images', 'zonalstats.png')) def group(self): return self.tr('Raster analysis') def groupId(self): return 'rasteranalysis' def flags(self): return super().flags() | QgsProcessingAlgorithm.FlagNoThreading def __init__(self): super().__init__() self.bandNumber = None self.columnPrefix = None self.selectedStats = None self.vectorLayer = None self.raster_interface = None self.raster_crs = None self.raster_units_per_pixel_x = None self.raster_units_per_pixel_y = None def initAlgorithm(self, config=None): self.STATS = OrderedDict([(self.tr('Count'), QgsZonalStatistics.Count), (self.tr('Sum'), QgsZonalStatistics.Sum), (self.tr('Mean'), QgsZonalStatistics.Mean), (self.tr('Median'), QgsZonalStatistics.Median), (self.tr('Std. dev.'), QgsZonalStatistics.StDev), (self.tr('Min'), QgsZonalStatistics.Min), (self.tr('Max'), QgsZonalStatistics.Max), (self.tr('Range'), QgsZonalStatistics.Range), (self.tr('Minority'), QgsZonalStatistics.Minority), (self.tr('Majority (mode)'), QgsZonalStatistics.Majority), (self.tr('Variety'), QgsZonalStatistics.Variety), (self.tr('Variance'), QgsZonalStatistics.Variance), (self.tr('All'), QgsZonalStatistics.All)]) self.addParameter(QgsProcessingParameterRasterLayer(self.INPUT_RASTER, self.tr('Raster layer'))) self.addParameter(QgsProcessingParameterBand(self.RASTER_BAND, self.tr('Raster band'), 1, self.INPUT_RASTER)) self.addParameter(QgsProcessingParameterVectorLayer(self.INPUT_VECTOR, self.tr('Vector layer containing zones'), [QgsProcessing.TypeVectorPolygon])) self.addParameter(QgsProcessingParameterString(self.COLUMN_PREFIX, self.tr('Output column prefix'), '_')) keys = list(self.STATS.keys()) self.addParameter(QgsProcessingParameterEnum(self.STATISTICS, self.tr('Statistics to calculate'), keys, allowMultiple=True, defaultValue=[0, 1, 2])) self.addOutput(QgsProcessingOutputVectorLayer(self.INPUT_VECTOR, self.tr('Zonal statistics'), QgsProcessing.TypeVectorPolygon)) def name(self): return 'zonalstatistics' def displayName(self): return self.tr('Zonal statistics') def prepareAlgorithm(self, parameters, context, feedback): self.bandNumber = self.parameterAsInt(parameters, self.RASTER_BAND, context) self.columnPrefix = self.parameterAsString(parameters, self.COLUMN_PREFIX, context) st = self.parameterAsEnums(parameters, self.STATISTICS, context) keys = list(self.STATS.keys()) self.selectedStats = 0 for i in st: self.selectedStats |= self.STATS[keys[i]] self.vectorLayer = self.parameterAsVectorLayer(parameters, self.INPUT_VECTOR, context) rasterLayer = self.parameterAsRasterLayer(parameters, self.INPUT_RASTER, context) self.raster_interface = rasterLayer.dataProvider().clone() self.raster_crs = rasterLayer.crs() self.raster_units_per_pixel_x = rasterLayer.rasterUnitsPerPixelX() self.raster_units_per_pixel_y = rasterLayer.rasterUnitsPerPixelY() return True def processAlgorithm(self, parameters, context, feedback): zs = QgsZonalStatistics(self.vectorLayer, self.raster_interface, self.raster_crs, self.raster_units_per_pixel_x, self.raster_units_per_pixel_y, self.columnPrefix, self.bandNumber, QgsZonalStatistics.Statistics(self.selectedStats)) zs.calculateStatistics(feedback) return {self.INPUT_VECTOR: self.vectorLayer}