copernicus_FG.py

from qgis.core import QgsProcessing
from qgis.core import QgsProcessingAlgorithm
from qgis.core import QgsProcessingMultiStepFeedback
from qgis.core import QgsProcessingParameterRasterLayer
from qgis.core import QgsProcessingParameterRasterDestination
from qgis.core import QgsCoordinateReferenceSystem
import processing


class Copernicus(QgsProcessingAlgorithm):

    def initAlgorithm(self, config=None):
        self.addParameter(QgsProcessingParameterRasterLayer('raster', 'raster', defaultValue=None))
        self.addParameter(QgsProcessingParameterRasterDestination('Final_resampled', 'final_resampled', createByDefault=True, defaultValue=None))

    def processAlgorithm(self, parameters, context, model_feedback):
        # Use a multi-step feedback, so that individual child algorithm progress reports are adjusted for the
        # overall progress through the model
        feedback = QgsProcessingMultiStepFeedback(5, model_feedback)
        results = {}
        outputs = {}

        input_raster = self.parameterAsRasterLayer(parameters, 'raster', context)

        Xmin = -180 + ((1 / 112) / 2)
        Xmax = 180 - ((1 / 112) / 2)
        Ymax = 80 - ((1 / 112) / 2)
        Ymin = -60 + ((1 / 112) / 2)

        pixelX = 1. / 112.
        pixelY = 1. / 112.

        stats = input_raster.dataProvider().bandStatistics(1)

        src_min = stats.minimumValue
        src_max = stats.maximumValue
        dst_min = stats.minimumValue
        dst_max = stats.maximumValue

        print(src_min, src_max, dst_min, dst_max)

        print("Checkpoint Charlie: ", Xmin, Xmax, Ymax, Ymin, pixelX)

        # Riclassifica con tabella
        alg_params = {
            'DATA_TYPE': 5,
            'INPUT_RASTER': parameters['raster'],
            'NODATA_FOR_MISSING': False,
            'NO_DATA': -9999,
            'RANGE_BOUNDARIES': 0,
            'RASTER_BAND': 1,
            'TABLE': [-1,1,1,1,255,0],
            'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
        }
        outputs['RiclassificaConTabella'] = processing.run('native:reclassifybytable', alg_params, context=context, feedback=feedback, is_child_algorithm=True)

        feedback.setCurrentStep(1)
        if feedback.isCanceled():
            return {}

        # translate Average
        tra_extra = "-of Gtiff -co COMPRESS=DEFLATE -co PREDICTOR=2 -co ZLEVEL=9 "
        tra_extra += " -projwin " + str(Xmin) + " " + str(Ymax) + " " + str(Xmax) + " " + str(Ymin)
        tra_extra += " -r average -tr " + str(pixelX) + " " + str(pixelY)
        tra_extra += " -scale " + str(src_min) + " " + str(src_max) + " " + str(dst_min) + " " + str(dst_max)

        alg_params = {
            'COPY_SUBDATASETS': False,
            'DATA_TYPE': 0,
            'EXTRA': tra_extra,
            'INPUT': parameters['raster'],
            'NODATA': None,
            'OPTIONS': '',
            'TARGET_CRS': None,
            'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
        }
        outputs['TranslateAverage'] = processing.run('gdal:translate', alg_params, context=context, feedback=feedback, is_child_algorithm=True)

        feedback.setCurrentStep(2)
        if feedback.isCanceled():
            return {}

        # Raster calculator
        alg_params = {
            'CELLSIZE': 0,
            'CRS': QgsCoordinateReferenceSystem('EPSG:4326'),
            'EXPRESSION': '\"\'Convertito\' from algorithm \'translate MODE\'@1\" * \"\'Convertito\' from algorithm \'translate Average\'@1\"',
            'EXTENT': None,
            'LAYERS': outputs['TranslateAverage']['OUTPUT'],
            'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
        }
        outputs['RasterCalculator'] = processing.run('qgis:rastercalculator', alg_params, context=context, feedback=feedback, is_child_algorithm=True)

        feedback.setCurrentStep(3)
        if feedback.isCanceled():
            return {}

        # translate MODE
        tra_extra_mode = "-of Gtiff -co COMPRESS=DEFLATE -co PREDICTOR=2 -co ZLEVEL=9 "
        tra_extra_mode += " -projwin " + str(Xmin) + " " + str(Ymax) + " " + str(Xmax) + " " + str(Ymin)
        tra_extra_mode += " -r mode -tr " + str(pixelX) + " " + str(pixelY)

        alg_params = {
            'COPY_SUBDATASETS': False,
            'DATA_TYPE': 0,
            'EXTRA': tra_extra_mode,
            'INPUT': outputs['RiclassificaConTabella']['OUTPUT'],
            'NODATA': None,
            'OPTIONS': '',
            'TARGET_CRS': None,
            'OUTPUT': QgsProcessing.TEMPORARY_OUTPUT
        }
        outputs['TranslateMode'] = processing.run('gdal:translate', alg_params, context=context, feedback=feedback, is_child_algorithm=True)

        feedback.setCurrentStep(4)
        if feedback.isCanceled():
            return {}

        # Riclassifica con tabella
        alg_params = {
            'DATA_TYPE': 5,
            'INPUT_RASTER': outputs['RasterCalculator']['OUTPUT'],
            'NODATA_FOR_MISSING': False,
            'NO_DATA': -9999,
            'RANGE_BOUNDARIES': 0,
            'RASTER_BAND': 1,
            'TABLE': [-9999,-1,-9999,1,9999,-9999],
            'OUTPUT': parameters['Final_resampled']
        }
        outputs['RiclassificaConTabella'] = processing.run('native:reclassifybytable', alg_params, context=context, feedback=feedback, is_child_algorithm=True)
        results['Final_resampled'] = outputs['RiclassificaConTabella']['OUTPUT']
        return results

    def name(self):
        return 'Copernicus'

    def displayName(self):
        return 'Copernicus'

    def group(self):
        return 'Copernicus'

    def groupId(self):
        return 'Copernicus'

    def createInstance(self):
        return Copernicus()