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| 1 | +# -*- coding: utf-8 -*- |
| 2 | + |
| 3 | +""" |
| 4 | +*************************************************************************** |
| 5 | + HypsometricCurves.py |
| 6 | + --------------------- |
| 7 | + Date : November 2014 |
| 8 | + Copyright : (C) 2014 by Alexander Bruy |
| 9 | + Email : alexander dot bruy at gmail dot com |
| 10 | +*************************************************************************** |
| 11 | +* * |
| 12 | +* This program is free software; you can redistribute it and/or modify * |
| 13 | +* it under the terms of the GNU General Public License as published by * |
| 14 | +* the Free Software Foundation; either version 2 of the License, or * |
| 15 | +* (at your option) any later version. * |
| 16 | +* * |
| 17 | +*************************************************************************** |
| 18 | +""" |
| 19 | + |
| 20 | +__author__ = 'Alexander Bruy' |
| 21 | +__date__ = 'November 2014' |
| 22 | +__copyright__ = '(C) 2014, Alexander Bruy' |
| 23 | + |
| 24 | +# This will get replaced with a git SHA1 when you do a git archive |
| 25 | + |
| 26 | +__revision__ = '$Format:%H$' |
| 27 | + |
| 28 | + |
| 29 | +import os |
| 30 | + |
| 31 | +import numpy |
| 32 | +from osgeo import gdal, ogr, osr |
| 33 | + |
| 34 | +from qgis.core import * |
| 35 | + |
| 36 | +from processing.core.GeoAlgorithm import GeoAlgorithm |
| 37 | +from processing.core.parameters import ParameterRaster |
| 38 | +from processing.core.parameters import ParameterVector |
| 39 | +from processing.core.parameters import ParameterNumber |
| 40 | +from processing.core.parameters import ParameterBoolean |
| 41 | +from processing.core.outputs import OutputDirectory |
| 42 | + |
| 43 | +from processing.tools import raster |
| 44 | +from processing.tools import dataobjects |
| 45 | +from processing.tools import vector |
| 46 | + |
| 47 | + |
| 48 | +class HypsometricCurves(GeoAlgorithm): |
| 49 | + |
| 50 | + INPUT_DEM = 'INPUT_DEM' |
| 51 | + BOUNDARY_LAYER = 'BOUNDARY_LAYER' |
| 52 | + STEP = 'STEP' |
| 53 | + USE_PERCENTAGE = 'USE_PERCENTAGE' |
| 54 | + OUTPUT_DIRECTORY = 'OUTPUT_DIRECTORY' |
| 55 | + |
| 56 | + def defineCharacteristics(self): |
| 57 | + self.name = 'Hypsometric curves' |
| 58 | + self.group = 'Raster tools' |
| 59 | + |
| 60 | + self.addParameter(ParameterRaster(self.INPUT_DEM, 'DEM to analyze')) |
| 61 | + self.addParameter(ParameterVector(self.BOUNDARY_LAYER, 'Boundary layer', |
| 62 | + ParameterVector.VECTOR_TYPE_POLYGON)) |
| 63 | + self.addParameter(ParameterNumber(self.STEP, 'Step', |
| 64 | + 0.0, 999999999.999999, 100.0)) |
| 65 | + self.addParameter(ParameterBoolean(self.USE_PERCENTAGE, |
| 66 | + 'Use % of area instead of absolute value', False)) |
| 67 | + |
| 68 | + self.addOutput(OutputDirectory(self.OUTPUT_DIRECTORY, 'Output directory')) |
| 69 | + |
| 70 | + def processAlgorithm(self, progress): |
| 71 | + rasterPath = self.getParameterValue(self.INPUT_DEM) |
| 72 | + layer = dataobjects.getObjectFromUri( |
| 73 | + self.getParameterValue(self.BOUNDARY_LAYER)) |
| 74 | + step = self.getParameterValue(self.STEP) |
| 75 | + percentage = self.getParameterValue(self.USE_PERCENTAGE) |
| 76 | + |
| 77 | + outputPath = self.getOutputValue(self.OUTPUT_DIRECTORY) |
| 78 | + |
| 79 | + rasterDS = gdal.Open(rasterPath, gdal.GA_ReadOnly) |
| 80 | + geoTransform = rasterDS.GetGeoTransform() |
| 81 | + rasterBand = rasterDS.GetRasterBand(1) |
| 82 | + noData = rasterBand.GetNoDataValue() |
| 83 | + |
| 84 | + cellXSize = abs(geoTransform[1]) |
| 85 | + cellYSize = abs(geoTransform[5]) |
| 86 | + rasterXSize = rasterDS.RasterXSize |
| 87 | + rasterYSize = rasterDS.RasterYSize |
| 88 | + |
| 89 | + rasterBBox = QgsRectangle(geoTransform[0], geoTransform[3] - cellYSize |
| 90 | + * rasterYSize, geoTransform[0] + cellXSize |
| 91 | + * rasterXSize, geoTransform[3]) |
| 92 | + rasterGeom = QgsGeometry.fromRect(rasterBBox) |
| 93 | + |
| 94 | + crs = osr.SpatialReference() |
| 95 | + crs.ImportFromProj4(str(layer.crs().toProj4())) |
| 96 | + |
| 97 | + memVectorDriver = ogr.GetDriverByName('Memory') |
| 98 | + memRasterDriver = gdal.GetDriverByName('MEM') |
| 99 | + |
| 100 | + features = vector.features(layer) |
| 101 | + count = len(features) |
| 102 | + total = 100.0 / float(count) |
| 103 | + |
| 104 | + for count, f in enumerate(features): |
| 105 | + geom = f.geometry() |
| 106 | + intersectedGeom = rasterGeom.intersection(geom) |
| 107 | + |
| 108 | + if intersectedGeom.isGeosEmpty(): |
| 109 | + progress.setInfo('Feature %d does not intersect raster or ' |
| 110 | + 'entirely located in NODATA area' % f.id()) |
| 111 | + continue |
| 112 | + |
| 113 | + fName = os.path.join( |
| 114 | + outputPath, 'hystogram_%s_%s.csv' % (layer.name(), f.id())) |
| 115 | + |
| 116 | + ogrGeom = ogr.CreateGeometryFromWkt(intersectedGeom.exportToWkt()) |
| 117 | + bbox = intersectedGeom.boundingBox() |
| 118 | + xMin = bbox.xMinimum() |
| 119 | + xMax = bbox.xMaximum() |
| 120 | + yMin = bbox.yMinimum() |
| 121 | + yMax = bbox.yMaximum() |
| 122 | + |
| 123 | + (startColumn, startRow) = raster.mapToPixel(xMin, yMax, geoTransform) |
| 124 | + (endColumn, endRow) = raster.mapToPixel(xMax, yMin, geoTransform) |
| 125 | + |
| 126 | + width = endColumn - startColumn |
| 127 | + height = endRow - startRow |
| 128 | + |
| 129 | + srcOffset = (startColumn, startRow, width, height) |
| 130 | + srcArray = rasterBand.ReadAsArray(*srcOffset) |
| 131 | + |
| 132 | + newGeoTransform = ( |
| 133 | + geoTransform[0] + srcOffset[0] * geoTransform[1], |
| 134 | + geoTransform[1], |
| 135 | + 0.0, |
| 136 | + geoTransform[3] + srcOffset[1] * geoTransform[5], |
| 137 | + 0.0, |
| 138 | + geoTransform[5] |
| 139 | + ) |
| 140 | + |
| 141 | + memVDS = memVectorDriver.CreateDataSource('out') |
| 142 | + memLayer = memVDS.CreateLayer('poly', crs, ogr.wkbPolygon) |
| 143 | + |
| 144 | + ft = ogr.Feature(memLayer.GetLayerDefn()) |
| 145 | + ft.SetGeometry(ogrGeom) |
| 146 | + memLayer.CreateFeature(ft) |
| 147 | + ft.Destroy() |
| 148 | + |
| 149 | + rasterizedDS = memRasterDriver.Create('', srcOffset[2], |
| 150 | + srcOffset[3], 1, gdal.GDT_Byte) |
| 151 | + rasterizedDS.SetGeoTransform(newGeoTransform) |
| 152 | + gdal.RasterizeLayer(rasterizedDS, [1], memLayer, burn_values=[1]) |
| 153 | + rasterizedArray = rasterizedDS.ReadAsArray() |
| 154 | + |
| 155 | + srcArray = numpy.nan_to_num(srcArray) |
| 156 | + masked = numpy.ma.MaskedArray(srcArray, |
| 157 | + mask=numpy.logical_or(srcArray == noData, |
| 158 | + numpy.logical_not(rasterizedArray))) |
| 159 | + |
| 160 | + self.calculateHypsometry(f.id(), fName, progress, masked, |
| 161 | + cellXSize, cellYSize, percentage, step) |
| 162 | + |
| 163 | + memVDS = None |
| 164 | + rasterizedDS = None |
| 165 | + progress.setPercentage(int(count * total)) |
| 166 | + |
| 167 | + rasterDS = None |
| 168 | + |
| 169 | + def calculateHypsometry(self, fid, fName, progress, data, pX, pY, |
| 170 | + percentage, step): |
| 171 | + out = dict() |
| 172 | + d = data.compressed() |
| 173 | + if d.size == 0: |
| 174 | + progress.setInfo('Feature %d does not intersect raster or ' |
| 175 | + 'entirely located in NODATA area' % fid) |
| 176 | + return |
| 177 | + |
| 178 | + minValue = d.min() |
| 179 | + maxValue = d.max() |
| 180 | + startValue = minValue |
| 181 | + tmpValue = minValue + step |
| 182 | + while startValue < maxValue: |
| 183 | + out[tmpValue] = ((startValue <= d) & (d < tmpValue)).sum() |
| 184 | + startValue = tmpValue |
| 185 | + tmpValue += step |
| 186 | + |
| 187 | + if percentage: |
| 188 | + multiplier = 100.0 / float(len(d.flat)) |
| 189 | + else: |
| 190 | + multiplier = pX * pY |
| 191 | + |
| 192 | + for k, v in out.iteritems(): |
| 193 | + out[k] = v * multiplier |
| 194 | + |
| 195 | + prev = None |
| 196 | + for i in sorted(out.items()): |
| 197 | + if prev is None: |
| 198 | + out[i[0]] = i[1] |
| 199 | + else: |
| 200 | + out[i[0]] = i[1] + out[prev] |
| 201 | + prev = i[0] |
| 202 | + |
| 203 | + writer = vector.TableWriter(fName, 'utf-8', ['Area', 'Elevation']) |
| 204 | + for i in sorted(out.items()): |
| 205 | + writer.addRecord([i[1], i[0]]) |
| 206 | + del writer |
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