QGIS/python/plugins/processing/algs/qgis/RasterLayerStatistics.py
2018-03-02 10:35:56 +02:00

124 lines
5.1 KiB
Python

# -*- coding: utf-8 -*-
"""
***************************************************************************
RasterLayerStatistics.py
---------------------
Date : January 2013
Copyright : (C) 2013 by Victor Olaya
Email : volayaf 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__ = 'Victor Olaya'
__date__ = 'January 2013'
__copyright__ = '(C) 2013, Victor Olaya'
# This will get replaced with a git SHA1 when you do a git archive
__revision__ = '$Format:%H$'
import codecs
from qgis.core import (QgsRectangle,
QgsRasterBandStats,
QgsProcessingParameterRasterLayer,
QgsProcessingParameterBand,
QgsProcessingParameterFileDestination,
QgsProcessingOutputNumber)
from processing.algs.qgis.QgisAlgorithm import QgisAlgorithm
class RasterLayerStatistics(QgisAlgorithm):
INPUT = 'INPUT'
BAND = 'BAND'
OUTPUT_HTML_FILE = 'OUTPUT_HTML_FILE'
MIN = 'MIN'
MAX = 'MAX'
RANGE = 'RANGE'
SUM = 'SUM'
MEAN = 'MEAN'
STD_DEV = 'STD_DEV'
SUM_OF_SQUARES = 'SUM_OF_SQUARES'
def group(self):
return self.tr('Raster analysis')
def groupId(self):
return 'rasteranalysis'
def __init__(self):
super().__init__()
def initAlgorithm(self, config=None):
self.addParameter(QgsProcessingParameterRasterLayer(self.INPUT,
self.tr('Input layer')))
self.addParameter(QgsProcessingParameterBand(self.BAND,
self.tr('Band number'),
1,
self.INPUT))
self.addParameter(QgsProcessingParameterFileDestination(self.OUTPUT_HTML_FILE, self.tr('Statistics'), self.tr('HTML files (*.html)'), None, True))
self.addOutput(QgsProcessingOutputNumber(self.MIN, self.tr('Minimum value')))
self.addOutput(QgsProcessingOutputNumber(self.MAX, self.tr('Maximum value')))
self.addOutput(QgsProcessingOutputNumber(self.RANGE, self.tr('Range')))
self.addOutput(QgsProcessingOutputNumber(self.SUM, self.tr('Sum')))
self.addOutput(QgsProcessingOutputNumber(self.MEAN, self.tr('Mean value')))
self.addOutput(QgsProcessingOutputNumber(self.STD_DEV, self.tr('Standard deviation')))
self.addOutput(QgsProcessingOutputNumber(self.SUM_OF_SQUARES, self.tr('Sum of the squares')))
def name(self):
return 'rasterlayerstatistics'
def displayName(self):
return self.tr('Raster layer statistics')
def processAlgorithm(self, parameters, context, feedback):
layer = self.parameterAsRasterLayer(parameters, self.INPUT, context)
band = self.parameterAsInt(parameters, self.BAND, context)
outputFile = self.parameterAsFileOutput(parameters, self.OUTPUT_HTML_FILE, context)
stat = layer.dataProvider().bandStatistics(band, QgsRasterBandStats.All, QgsRectangle(), 0)
data = []
data.append(self.tr('Analyzed file: {} (band {})').format(layer.source(), band))
data.append(self.tr('Minimum value: {}').format(stat.minimumValue))
data.append(self.tr('Maximum value: {}').format(stat.maximumValue))
data.append(self.tr('Range: {}').format(stat.range))
data.append(self.tr('Sum: {}').format(stat.sum))
data.append(self.tr('Mean value: {}').format(stat.mean))
data.append(self.tr('Standard deviation: {}').format(stat.stdDev))
data.append(self.tr('Sum of the squares: {}').format(stat.sumOfSquares))
results = {self.MIN: stat.minimumValue,
self.MAX: stat.maximumValue,
self.RANGE: stat.range,
self.SUM: stat.sum,
self.MEAN: stat.mean,
self.STD_DEV: stat.stdDev,
self.SUM_OF_SQUARES: stat.sumOfSquares}
if outputFile:
self.createHTML(outputFile, data)
results[self.OUTPUT_HTML_FILE] = outputFile
return results
def createHTML(self, outputFile, algData):
with codecs.open(outputFile, 'w', encoding='utf-8') as f:
f.write('<html><head>\n')
f.write('<meta http-equiv="Content-Type" content="text/html; \
charset=utf-8" /></head><body>\n')
for s in algData:
f.write('<p>' + str(s) + '</p>\n')
f.write('</body></html>\n')