def _testGeneratePyramids(self, pyramidFormat):
tmpName = tempfile.mktemp(suffix='.tif')
source = QgsRasterLayer(
os.path.join(self.testDataDir, 'raster', 'byte.tif'), 'my', 'gdal')
self.assertTrue(source.isValid())
provider = source.dataProvider()
fw = QgsRasterFileWriter(tmpName)
fw.setBuildPyramidsFlag(QgsRaster.PyramidsFlagYes)
fw.setPyramidsFormat(pyramidFormat)
fw.setPyramidsList([2])
pipe = QgsRasterPipe()
self.assertTrue(pipe.set(provider.clone()))
projector = QgsRasterProjector()
projector.setCrs(provider.crs(), provider.crs())
self.assertTrue(pipe.insert(2, projector))
self.assertEqual(
fw.writeRaster(pipe, provider.xSize(), provider.ySize(),
provider.extent(), provider.crs()), 0)
del fw
ds = gdal.Open(tmpName)
self.assertEqual(ds.GetRasterBand(1).GetOverviewCount(), 1)
fl = ds.GetFileList()
if pyramidFormat == QgsRaster.PyramidsGTiff:
self.assertEqual(len(fl), 2, fl)
self.assertIn('.ovr', fl[1])
elif pyramidFormat == QgsRaster.PyramidsInternal:
self.assertEqual(len(fl), 1, fl)
elif pyramidFormat == QgsRaster.PyramidsErdas:
self.assertEqual(len(fl), 2, fl)
self.assertIn('.aux', fl[1])
os.unlink(tmpName)
def save_raster_as_geotif(raster_layer, project_dir):
"""Save raster layer as GeoTiff in the project directory."""
new_raster_filename = get_unique_filename(raster_layer.name() + ".tif")
layer_filename = os.path.join(project_dir,
os.path.basename(new_raster_filename))
# Get data type info to set a proper compression type
dp = raster_layer.dataProvider()
is_byte_data = [
dp.dataType(i) <= Qgis.Byte for i in range(raster_layer.bandCount())
]
compression = "JPEG" if all(is_byte_data) else "LZW"
writer_options = [f"COMPRESS={compression}", "TILED=YES"]
raster_writer = QgsRasterFileWriter(layer_filename)
raster_writer.setCreateOptions(writer_options)
raster_writer.setBuildPyramidsFlag(QgsRaster.PyramidsFlagYes)
raster_writer.setPyramidsFormat(QgsRaster.PyramidsInternal)
raster_writer.setPyramidsList([2, 4, 8, 16, 32, 64, 128])
write_raster(raster_layer, raster_writer, layer_filename)
