GDAL WriteArray問題

Question

我正在利用python GDAL將一個柵格數據寫入.tif文件。下面的代碼：

import numpy, sys 
from osgeo import gdal, utils 
from osgeo.gdalconst import * 

# register all of the GDAL drivers 
gdal.AllRegister() 

# open the image 
inDs = gdal.Open("C:\\Documents and Settings\\patrick\\Desktop\\tiff elevation\\EBK1KM\\color_a1.tif",GDT_UInt16) 
if inDs is None: 
    print "couldn't open input dataset" 
    sys.exit(1) 
else: 
    print "opening was successful!" 
cols = inDs.RasterXSize 
rows = inDs.RasterYSize 
bands = inDs.RasterCount 
driver = inDs.GetDriver() 
driver.Create("C:\\Documents and Settings\\patrick\\Desktop\\tiff elevation\\EBK1KM\\newfile.tif",cols,rows,3,GDT_UInt16) 
outDs = gdal.Open("C:\\Documents and Settings\\patrick\\Desktop\\tiff elevation\\EBK1KM\\newfile.tif") 

if outDs is None: 
    print "failure to create new file" 
    sys.exit(1) 


outBand1 = outDs.GetRasterBand(1) 
outBand2 = outDs.GetRasterBand(2) 
outBand3 = outDs.GetRasterBand(3) 
data1 = inDs.GetRasterBand(1).ReadAsArray() 
data2 = inDs.GetRasterBand(2).ReadAsArray() 
data3 = inDs.GetRasterBand(3).ReadAsArray() 

outBand1.WriteArray(data1,0,0) 
outBand2.WriteArray(data2,0,0) 
outBand3.WriteArray(data3,0,0) 

print "before closing out the file" 
print outDs.GetRasterBand(1).ReadAsArray(700,700,5,5) 
print outDs.GetRasterBand(2).ReadAsArray(700,700,5,5) 
print outDs.GetRasterBand(3).ReadAsArray(700,700,5,5) 

outDs.SetProjection(inDs.GetProjection()) 
outDs.SetGeoTransform(inDs.GetGeoTransform()) 

outDs = None 
outDs = gdal.Open("C:\\Documents and Settings\\patrick\\Desktop\\tiff elevation\\EBK1KM\\newfile.tif") 
print "after reopening" 
print outDs.GetRasterBand(1).ReadAsArray(700,700,5,5) 
print outDs.GetRasterBand(2).ReadAsArray(700,700,5,5) 
print outDs.GetRasterBand(3).ReadAsArray(700,700,5,5) 

輸出數據集的關閉和重新打開之間得到的輸出是不同的：

before closing out the file 
[[ 36 35 55 121 0] 
[ 54 0 111 117 0] 
[ 0 117 152 56 0] 
[ 89 122 56 0 0] 
[102 107 0 25 53]] 
[[ 68 66 126 200 0] 
[ 78 0 166 157 0] 
[ 0 235 203 70 0] 
[229 251 107 0 0] 
[241 203 0 42 121]] 
[[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0]] 
after reopening 
[[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0]] 
[[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0]] 
[[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0] 
[0 0 0 0 0]] 

有一些命令我失蹤，以確保文件被寫入並保存在將變量設置爲None之前？我試着將沒有運氣以下兩種情況：

outband1.FlushCache() 
outDs.FlushCache() 

Answer 1

你不需要Create然後Open光柵（你在讀GA_ReadOnly）。您在開始時也不需要gdal.AllRegister()，因爲在將GDAL加載到Python時已經調用它（請參閱GDAL API Tutorial）。

拿起某處以上（含修改）：

# Create a new raster data source 
outDs = driver.Create(out_fname, cols, rows, 3, gdal.GDT_UInt16) 

# Write metadata 
outDs.SetGeoTransform(inDs.GetGeoTransform()) 
outDs.SetProjection(inDs.GetProjection()) 

# Write raster data sets 
for i in range(3): 
    outBand = outDs.GetRasterBand(i + 1) 
    outBand.WriteArray(data[i]) 

# Close raster file 
outDs = None 

有時我添加此以確保文件被完全釋放，並防止遇到了一些gotchas：

del outDs, outBand