python gdal遥感影像基础操作（读写、增加波段、添加坐标系）
1.读写
def read_img(filename):
dataset=gdal.Open(filename)
im_width = dataset.RasterXSize
im_height = dataset.RasterYSize
im_geotrans = dataset.GetGeoTransform()
im_proj = dataset.GetProjection()
im_data = dataset.ReadAsArray(0,0,im_width,im_height)
del dataset
return im_proj,im_geotrans,im_width, im_height,im_data
def write_img(filename, im_proj, im_geotrans, im_data):
if 'int8' in im_data.dtype.name:
datatype = gdal.GDT_Byte
elif 'int16' in im_data.dtype.name:
datatype = gdal.GDT_UInt16
else:
datatype = gdal.GDT_Float32
if len(im_data.shape) == 3:
im_bands, im_height, im_width = im_data.shape
else:
im_bands, (im_height, im_width) = 1,im_data.shape
driver = gdal.GetDriverByName("GTiff")
dataset = driver.Create(filename, im_width, im_height, im_bands, datatype)
dataset.SetGeoTransform(im_geotrans)
dataset.SetProjection(im_proj)
if im_bands == 1:
dataset.GetRasterBand(1).WriteArray(im_data)
else:
for i in range(im_bands):
dataset.GetRasterBand(i+1).WriteArray(im_data[i])
2.增加波段
# -*- coding: utf-8 -*-
import os
import cv2
from osgeo import gdal
import numpy as np
import time
#多波段
def add_band(imgPath1, imgPath2, outpath):
(filepath,fullname) = os.path.split(imgPath1)
filename = fullname.split('.')[0]
driver = gdal.GetDriverByName('GTiff')
driver.Register()
dataset = gdal.Open(imgPath1)
bands = dataset.RasterCount
geotrans = dataset.GetGeoTransform()
proj = dataset.GetProjection()
im_width=dataset.RasterXSize #col
im_height=dataset.RasterYSize #row
datas = dataset.ReadAsArray(0,0,1,1)
if 'int8' in datas.dtype.name:
datatype = gdal.GDT_Byte
elif 'int16' in datas.dtype.name:
datatype = gdal.GDT_UInt16
else:
datatype = gdal.GDT_Float32
dataset = gdal.Open(imgPath2)
bands2 = dataset.RasterCount
new_bands = bands + bands2
slice_img = driver.Create(outpath + filename + '.tif',im_width,im_height,new_bands,datatype)
for band in range(new_bands-1):
slice_img.GetRasterBand(band + 1).WriteArray(dataset.GetRasterBand(band + 1).ReadAsArray(0,0,im_width,im_height))
for band in range(bands,new_bands):
slice_img.GetRasterBand(band + 1).WriteArray(dataset.GetRasterBand(band + 1).ReadAsArray(0,0,im_width,im_height))
slice_img.SetGeoTransform(geotrans)
slice_img.SetProjection(proj)
#单波段
def add_band2(imgPath, addPath, outPath):
driver = gdal.GetDriverByName('GTiff')
driver.Register()
dataset = gdal.Open(imgPath)
bands = dataset.RasterCount
im_width=dataset.RasterXSize #col
im_height=dataset.RasterYSize #row
geotrans = dataset.GetGeoTransform()
proj = dataset.GetProjection()
data = dataset.ReadAsArray(0,0,im_width,im_height)
dataset2 = gdal.Open(addPath)
data2 = dataset.ReadAsArray(0,0,im_width,im_height)
slice_img = driver.Create(outPath,im_width,im_height,4,gdal.GDT_Byte)
for band in range(3):
slice_img.GetRasterBand(band + 1).WriteArray(dataset.GetRasterBand(band + 1).ReadAsArray(0,0,im_width,im_height))
for band in range(3,4):
slice_img.GetRasterBand(band+1).WriteArray(dataset2.GetRasterBand(1).ReadAsArray(0,0,im_width,im_height))
slice_img.SetGeoTransform(geotrans)
slice_img.SetProjection(proj)
if __name__=='__main__':
add_band2('D:/wcs/test/1/0717/image_3/fuse3.tif', 'D:/wcs/test/1/0717/image_3/img_log.tif', 'D:/wcs/test/1/0717/image_3/fuse4.tif')
3.添加坐标系
# -*- coding: utf-8 -*-
import os
import cv2
from osgeo import gdal
import numpy as np
import time
def addcoor(img1,img2):
dataset1 = gdal.Open(img1)
geotrans = dataset1.GetGeoTransform()
proj = dataset1.GetProjection()
dataset2 = gdal.Open(img2,1)
dataset2.SetGeoTransform(geotrans)
dataset2.SetProjection(proj)
del dataset1
del dataset2
if __name__=='__main__':
addcoor('D:/wcs/test/outhillshd.tif','D:/wcs/test/outhillshd_edge.tif')
# path = 'D:/wcs/test/dem_test/sample_16bit/'
# imgs = os.listdir(path)
# for img in imgs:
# addcoor(os.path.join(path,img),'D:/wcs/test/dem_test/img/')