用Python剪裁栅格数据，以及如何用Python读取shapefile

1. 通过GDAL warp来进行剪裁

import gdal
import os


in_shape = r'D:\shape_cn\guo.shp'
in_dir = r'D:\TEST'
out_dir = r'D:\TEST\output'

file_list = os.listdir(in_dir)
for file in file_list:
    if file.endswith('.tif'):
        print('Processing >>> ' + file)
        in_raster = gdal.Open(os.path.join(in_dir, file))
        out_raster = os.path.join(out_dir, file)
        ds = gdal.Warp(out_raster,
                    in_raster,
                    format = 'GTiff',
                    cutlineDSName = in_shape,
                    # cutlineWhere="FIELD = 'whatever'", # clip specific feature 
                    dstNodata = 0) # set nodata value
        ds = None # close dataset
    else:
        print("No '.tif' file found ...")
print('..........ALL DONE..........')

2. 用rasterio来剪裁

import fiona
import rasterio
from rasterio.mask import mask


in_file = r'G:\test\test.tif'
shp = r"G:\Shapefiles\shape_cn\guo.shp"

with fiona.open(shp, "r", encoding='utf-8') as shapefile:
    # obtain all the points of the polygon
    geoms = [feature["geometry"] for feature in shapefile]

with rasterio.open(in_file) as src:
    out_image, out_transform = mask(src, geoms, crop=True)
    out_meta = src.meta.copy()
# update metadata for the output file
out_meta.update({"driver": "GTiff",
                 "height": out_image.shape[1],
                 "width": out_image.shape[2],
                 "transform": out_transform})

with rasterio.open(r"G:\test\masked.tif", "w", **out_meta) as dest:
    dest.write(out_image)

print('... ... ... COMPLETED ... ... ...')

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Python读取shapefile有以下几种方法：

1. Fiona

import fiona
shape = fiona.open("my_shapefile.shp")
print shape.schema
{'geometry': 'LineString', 'properties': OrderedDict([(u'FID', 'float:11')])}
#first feature of the shapefile
first = shape.next()
print first # (GeoJSON format)
{'geometry': {'type': 'LineString', 'coordinates': [(0.0, 0.0), (25.0, 10.0), (50.0, 50.0)]}, 'type': 'Feature', 'id': '0', 'properties': OrderedDict([(u'FID', 0.0)])}

2. PyShp

import shapefile
shape = shapefile.Reader("my_shapefile.shp")
#first feature of the shapefile
feature = shape.shapeRecords()[0]
first = feature.shape.__geo_interface__  
print first # (GeoJSON format)
{'type': 'LineString', 'coordinates': ((0.0, 0.0), (25.0, 10.0), (50.0, 50.0))}

3. ogr

from osgeo import ogr
file = ogr.Open("my_shapefile.shp")
shape = file.GetLayer(0)
#first feature of the shapefile
feature = shape.GetFeature(0)
first = feature.ExportToJson()
print first # (GeoJSON format)
{"geometry": {"type": "LineString", "coordinates": [[0.0, 0.0], [25.0, 10.0], [50.0, 50.0]]}, "type": "Feature", "properties": {"FID": 0.0}, "id": 0}

4. geopandas

import geopandas as gpd
shapefile = gpd.read_file("shapefile.shp")
print(shapefile)