本文整理汇总了Python中qgis.core.QgsRasterLayer.setContrastEnhancementAlgorithm方法的典型用法代码示例。如果您正苦于以下问题：Python QgsRasterLayer.setContrastEnhancementAlgorithm方法的具体用法？Python QgsRasterLayer.setContrastEnhancementAlgorithm怎么用？Python QgsRasterLayer.setContrastEnhancementAlgorithm使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类qgis.core.QgsRasterLayer的用法示例。
在下文中一共展示了QgsRasterLayer.setContrastEnhancementAlgorithm方法的3个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: toMapLayer
# 需要导入模块: from qgis.core import QgsRasterLayer [as 别名]
# 或者: from qgis.core.QgsRasterLayer import setContrastEnhancementAlgorithm [as 别名]
def toMapLayer(self):
from qgis.core import QgsRasterLayer
uri=self.uri()
schema = "schema="+self.schemaName() if self.schemaName() else ''
pgrasterUri= ('PG: dbname=%s host=%s user=%s password=%s port=%s mode=2 %s table=%s') % (uri.database(), uri.host(), uri.username(), uri.password(), uri.port(),schema,self.name)
rasterLayer=QgsRasterLayer(pgrasterUri, self.name)
rasterLayer.setContrastEnhancementAlgorithm("StretchToMinimumMaximum")
return rasterLayer示例2: testTransparency
# 需要导入模块: from qgis.core import QgsRasterLayer [as 别名]
# 或者: from qgis.core.QgsRasterLayer import setContrastEnhancementAlgorithm [as 别名]
def testTransparency(self):
myPath = os.path.join(unitTestDataPath('raster'),
'band1_float32_noct_epsg4326.tif')
myFileInfo = QFileInfo(myPath)
myBaseName = myFileInfo.baseName()
myRasterLayer = QgsRasterLayer(myPath, myBaseName)
myMessage = 'Raster not loaded: %s' % myPath
assert myRasterLayer.isValid(), myMessage
renderer = QgsSingleBandGrayRenderer(myRasterLayer.dataProvider(), 1)
myRasterLayer.setRenderer(renderer)
myRasterLayer.setContrastEnhancementAlgorithm(
QgsContrastEnhancement.StretchToMinimumMaximum,
QgsRasterLayer.ContrastEnhancementMinMax)
myContrastEnhancement = myRasterLayer.renderer().contrastEnhancement()
#print ("myContrastEnhancement.minimumValue = %.17g" %
# myContrastEnhancement.minimumValue())
#print ("myContrastEnhancement.maximumValue = %.17g" %
# myContrastEnhancement.maximumValue())
# Unfortunately the minimum/maximum values calculated in C++ and Python
# are slightly different (e.g. 3.3999999521443642e+38 x
# 3.3999999521444001e+38)
# It is not clear where the precision is lost.
# We set the same values as C++.
myContrastEnhancement.setMinimumValue(-3.3319999287625854e+38)
myContrastEnhancement.setMaximumValue(3.3999999521443642e+38)
#myType = myRasterLayer.dataProvider().dataType(1);
#myEnhancement = QgsContrastEnhancement(myType);
myTransparentSingleValuePixelList = []
rasterTransparency = QgsRasterTransparency()
myTransparentPixel1 = \
QgsRasterTransparency.TransparentSingleValuePixel()
myTransparentPixel1.min = -2.5840000772112106e+38
myTransparentPixel1.max = -1.0879999684602689e+38
myTransparentPixel1.percentTransparent = 50
myTransparentSingleValuePixelList.append(myTransparentPixel1)
myTransparentPixel2 = \
QgsRasterTransparency.TransparentSingleValuePixel()
myTransparentPixel2.min = 1.359999960575336e+37
myTransparentPixel2.max = 9.520000231087593e+37
myTransparentPixel2.percentTransparent = 70
myTransparentSingleValuePixelList.append(myTransparentPixel2)
rasterTransparency.setTransparentSingleValuePixelList(
myTransparentSingleValuePixelList)
rasterRenderer = myRasterLayer.renderer()
assert rasterRenderer
rasterRenderer.setRasterTransparency(rasterTransparency)
QgsMapLayerRegistry.instance().addMapLayers([ myRasterLayer, ])
myMapRenderer = QgsMapRenderer()
myLayers = QStringList()
myLayers.append(myRasterLayer.id())
myMapRenderer.setLayerSet(myLayers)
myMapRenderer.setExtent(myRasterLayer.extent())
myChecker = QgsRenderChecker()
myChecker.setControlName("expected_raster_transparency")
myChecker.setMapRenderer(myMapRenderer)
myResultFlag = myChecker.runTest("raster_transparency_python");
assert myResultFlag, "Raster transparency rendering test failed"示例3: toMapLayer
# 需要导入模块: from qgis.core import QgsRasterLayer [as 别名]
# 或者: from qgis.core.QgsRasterLayer import setContrastEnhancementAlgorithm [as 别名]
def toMapLayer(self):
from qgis.core import QgsRasterLayer
rl = QgsRasterLayer(self.gdalUri(), self.name)
if rl.isValid():
rl.setContrastEnhancementAlgorithm("StretchToMinimumMaximum")
return rl