def generate_lat_raster(cfg):
"""Generate latitude raster"""
dem_file = cfg.spatials.filldem
ds = RasterUtilClass.read_raster(dem_file)
src_srs = ds.srs
if not src_srs.ExportToProj4():
raise ValueError('The source raster %s has not coordinate, '
'which is required!' % dem_file)
dst_srs = osr_SpatialReference()
dst_srs.ImportFromEPSG(4326) # WGS84
# dst_wkt = dst_srs.ExportToWkt()
transform = osr_CoordinateTransformation(src_srs, dst_srs)
point_ll = ogr_CreateGeometryFromWkt('POINT (%f %f)' % (ds.xMin, ds.yMin))
point_ur = ogr_CreateGeometryFromWkt('POINT (%f %f)' % (ds.xMax, ds.yMax))
point_ll.Transform(transform)
point_ur.Transform(transform)
lower_lat = point_ll.GetY()
up_lat = point_ur.GetY()
rows = ds.nRows
cols = ds.nCols
delta_lat = (up_lat - lower_lat) / float(rows)
def cal_cell_lat(row, col):
"""calculate latitude of cell by row number"""
return up_lat - (row + 0.5) * delta_lat
data_lat = fromfunction(cal_cell_lat, (rows, cols))
data_lat = where(ds.validZone, data_lat, ds.data)
RasterUtilClass.write_gtiff_file(cfg.spatials.cell_lat, rows, cols, data_lat,
ds.geotrans, ds.srs,
ds.noDataValue, GDT_Float32)
def read_raster(raster_file):
"""Read raster by GDAL.
Args:
raster_file: raster file path.
Returns:
Raster object.
"""
ds = gdal_Open(raster_file)
band = ds.GetRasterBand(1)
data = band.ReadAsArray()
xsize = band.XSize
ysize = band.YSize
nodata_value = band.GetNoDataValue()
geotrans = ds.GetGeoTransform()
dttype = band.DataType
srs = osr_SpatialReference()
srs.ImportFromWkt(ds.GetProjection())
# print(srs.ExportToProj4())
if nodata_value is None:
nodata_value = DEFAULT_NODATA
band = None
ds = None
return Raster(ysize, xsize, data, nodata_value, geotrans, srs, dttype)
def read_raster(raster_file):
"""Read raster by GDAL.
Args:
raster_file: raster file path.
Returns:
Raster object.
"""
ds = gdal_Open(raster_file)
band = ds.GetRasterBand(1)
data = band.ReadAsArray()
xsize = band.XSize
ysize = band.YSize
nodata_value = band.GetNoDataValue()
geotrans = ds.GetGeoTransform()
dttype = band.DataType
srs = osr_SpatialReference()
srs.ImportFromWkt(ds.GetProjection())
# print(srs.ExportToProj4())
if nodata_value is None:
nodata_value = DEFAULT_NODATA
band = None
ds = None
return Raster(ysize, xsize, data, nodata_value, geotrans, srs, dttype)
def generate_lat_raster(cfg):
"""Generate latitude raster"""
dem_file = cfg.spatials.filldem
ds = RasterUtilClass.read_raster(dem_file)
src_srs = ds.srs
if not src_srs.ExportToProj4():
raise ValueError('The source raster %s has not coordinate, '
'which is required!' % dem_file)
dst_srs = osr_SpatialReference()
dst_srs.ImportFromEPSG(4326) # WGS84
# dst_wkt = dst_srs.ExportToWkt()
transform = osr_CoordinateTransformation(src_srs, dst_srs)
point_ll = ogr_CreateGeometryFromWkt('POINT (%f %f)' % (ds.xMin, ds.yMin))
point_ur = ogr_CreateGeometryFromWkt('POINT (%f %f)' % (ds.xMax, ds.yMax))
point_ll.Transform(transform)
point_ur.Transform(transform)
lower_lat = point_ll.GetY()
up_lat = point_ur.GetY()
rows = ds.nRows
cols = ds.nCols
delta_lat = (up_lat - lower_lat) / float(rows)
def cal_cell_lat(row, col):
"""calculate latitude of cell by row number"""
return up_lat - (row + 0.5) * delta_lat
data_lat = fromfunction(cal_cell_lat, (rows, cols))
data_lat = where(ds.validZone, data_lat, ds.data)
RasterUtilClass.write_gtiff_file(cfg.spatials.cell_lat, rows, cols, data_lat,
ds.geotrans, ds.srs,
ds.noDataValue, GDT_Float32)
def raster2shp(rasterfile,
vectorshp,
layername=None,
fieldname=None,
band_num=1,
mask='default'):
"""Convert raster to ESRI shapefile"""
FileClass.remove_files(vectorshp)
FileClass.check_file_exists(rasterfile)
# this allows GDAL to throw Python Exceptions
gdal.UseExceptions()
src_ds = gdal.Open(rasterfile)
if src_ds is None:
print('Unable to open %s' % rasterfile)
sys.exit(1)
try:
srcband = src_ds.GetRasterBand(band_num)
except RuntimeError as e:
# for example, try GetRasterBand(10)
print('Band ( %i ) not found, %s' % (band_num, e))
sys.exit(1)
if mask == 'default':
maskband = srcband.GetMaskBand()
elif mask is None or mask.upper() == 'NONE':
maskband = None
else:
mask_ds = gdal.Open(mask)
maskband = mask_ds.GetRasterBand(1)
# create output datasource
if layername is None:
layername = FileClass.get_core_name_without_suffix(rasterfile)
drv = ogr_GetDriverByName(str('ESRI Shapefile'))
dst_ds = drv.CreateDataSource(vectorshp)
srs = None
if src_ds.GetProjection() != '':
srs = osr_SpatialReference()
srs.ImportFromWkt(src_ds.GetProjection())
dst_layer = dst_ds.CreateLayer(str(layername), srs=srs)
if fieldname is None:
fieldname = layername.upper()
fd = ogr_FieldDefn(str(fieldname), OFTInteger)
dst_layer.CreateField(fd)
dst_field = 0
result = gdal.Polygonize(srcband,
maskband,
dst_layer,
dst_field, ['8CONNECTED=8'],
callback=None)
return result
def raster2shp(rasterfile, vectorshp, layername=None, fieldname=None,
band_num=1, mask='default'):
"""Convert raster to ESRI shapefile"""
FileClass.remove_files(vectorshp)
FileClass.check_file_exists(rasterfile)
# this allows GDAL to throw Python Exceptions
gdal.UseExceptions()
src_ds = gdal.Open(rasterfile)
if src_ds is None:
print('Unable to open %s' % rasterfile)
sys.exit(1)
try:
srcband = src_ds.GetRasterBand(band_num)
except RuntimeError as e:
# for example, try GetRasterBand(10)
print('Band ( %i ) not found, %s' % (band_num, e))
sys.exit(1)
if mask == 'default':
maskband = srcband.GetMaskBand()
elif mask is None or mask.upper() == 'NONE':
maskband = None
else:
mask_ds = gdal.Open(mask)
maskband = mask_ds.GetRasterBand(1)
# create output datasource
if layername is None:
layername = FileClass.get_core_name_without_suffix(rasterfile)
drv = ogr_GetDriverByName(str('ESRI Shapefile'))
dst_ds = drv.CreateDataSource(vectorshp)
srs = None
if src_ds.GetProjection() != '':
srs = osr_SpatialReference()
srs.ImportFromWkt(src_ds.GetProjection())
dst_layer = dst_ds.CreateLayer(str(layername), srs=srs)
if fieldname is None:
fieldname = layername.upper()
fd = ogr_FieldDefn(str(fieldname), OFTInteger)
dst_layer.CreateField(fd)
dst_field = 0
result = gdal.Polygonize(srcband, maskband, dst_layer, dst_field,
['8CONNECTED=8'], callback=None)
return result