使用 Python 编写图像文件时遇到问题答案

【问题标题】：Having Trouble Writing Image Files with Python使用 Python 编写图像文件时遇到问题
【发布时间】：2016-10-26 13:48:43
【问题描述】：

我在将图像文件写入 PC 上的文件夹时遇到了一些问题。正如您在下面的脚本中看到的那样，我使用了 os.path.expanduser，因为我打算使用将此脚本发送到另一台计算机，该计算机显然与我的本地 PC 没有相同的文件路径。当我运行这个脚本时，gdal_calc 运行正常，但是，没有输出？任何关于如何创建输出文件或可能导致图像消失的想法将不胜感激。

#!/usr/bin/env bash

import subprocess
from subprocess import call
import sys
import os


# Set constants
# The pathway to the image files are nested within the '--outfile=' command

inHVFile = os.path.expanduser('~\\Desktop\\Zeros\\ZerosHV-Test-3.img')
outPlacement = os.path.expanduser('~\\Desktop\\newHVZeros.img')
outVFile = '--outfile=outPlacement'
outVFile_1 = '--outfile=outPlacement_1'
inVHFile = os.path.expanduser('~\\Desktop\\Zeros\\ZerosVH-Test-3.img')
outPlacement_1 = os.path.expanduser('~\\Desktop\\newVHZeros.img')



subprocess.call([sys.executable, 'C:\\Program Files (x86)\\GDAL\\gdal_calc.py','-A', inHVFile, outVFile, '--calc=A+1'])

subprocess.call([sys.executable, 'C:\\Program Files (x86)\\GDAL\\gdal_calc.py','-A', inVHFile, outVFile_1, '--calc=A+1'])

【问题讨论】：

标签： python-3.x operating-system gdal

【解决方案1】：

您的脚本可能存在一些问题。我在下面对它们进行了注释。

#!/usr/bin/env bash
#              ^^^^  THIS ISN'T A BASH SCRIPT, THE ENVIRONMENT IS PYTHON

import subprocess
from subprocess import call
import sys
import os


# Set constants
# The pathway to the image files are nested within the '--outfile=' command
# YOU CANNOT NEST A VARIABLE INSIDE A STRING LIKE YOU ARE TRYING TO DO

inHVFile = os.path.expanduser('~\\Desktop\\Zeros\\ZerosHV-Test-3.img')
outPlacement = os.path.expanduser('~\\Desktop\\newHVZeros.img')
outVFile = '--outfile=outPlacement'
#                     ^^^^^^^^^^^^ THIS WILL NOT EXPAND TO YOUR outPlacement VARIABLE
outVFile_1 = '--outfile=outPlacement_1'
#                       ^^^^^^^^^^^^^^ THIS WILL NOT EXPAND TO YOUR outPlacement_1 VARIABLE
inVHFile = os.path.expanduser('~\\Desktop\\Zeros\\ZerosVH-Test-3.img')
outPlacement_1 = os.path.expanduser('~\\Desktop\\newVHZeros.img')



subprocess.call([sys.executable, 'C:\\Program Files (x86)\\GDAL\\gdal_calc.py','-A', inHVFile, outVFile, '--calc=A+1']) 
# This call to gdal_calc.py will produce a file called "outPlacement.tif" in whatever directory the script is run

subprocess.call([sys.executable, 'C:\\Program Files (x86)\\GDAL\\gdal_calc.py','-A', inVHFile, outVFile_1, '--calc=A+1'])
# This call to gdal_calc.py will produce a file called "outPlacement_1.tif" in whatever directory the script is run

这是一个正确的版本：

#!/usr/bin/env python

import subprocess
import sys
import os

# Set constants
inHVFile = os.path.expanduser('~\\Desktop\\Zeros\\ZerosHV-Test-3.img')
outPlacement = os.path.expanduser('~\\Desktop\\newHVZeros.img')
outVFile = '--outfile=' + outPlacement

inVHFile = os.path.expanduser('~\\Desktop\\Zeros\\ZerosVH-Test-3.img')
outPlacement_1 = os.path.expanduser('~\\Desktop\\newVHZeros.img')
outVFile_1 = '--outfile=' + outPlacement_1

subprocess.call([sys.executable, 'C:\\Program Files (x86)\\GDAL\\gdal_calc.py','-A', inHVFile, outVFile, '--calc=A+1'])
subprocess.call([sys.executable, 'C:\\Program Files (x86)\\GDAL\\gdal_calc.py','-A', inVHFile, outVFile_1, '--calc=A+1'])

【讨论】：