PDF转换后文件打开奇怪

Question

在使用 pdftotext 终端命令（我是运行 Ubuntu 17.04）将文本从 PDF 剥离到文本 (.txt) 文件后，我尝试从文件中读取，我我得到了非常奇怪的输出。我用一个只有一个词的 txt 测试了代码：test。该代码有效。它完美地从文件中打印出来，这告诉我它要么是 pdftotext 的错误，要么是编码的错误。真正让我感动并让我来到这里的是文件在文本编辑器中正常打开，所有测试都表明该文件是标准的 UTF-8。这是我的 PDF stripped text file，创建于：

import tkinter
from tkinter.filedialog import askopenfilename
import subprocess
from subprocess import *
import os
from tkinter import Listbox
import sys
from tkinter import Scrollbar
from tkinter import Frame
from tkinter import Label
from tkinter import messagebox
from tkinter import Button

#win32, cygwin, linux, linux2, darwin

def chooser():
    returnedValue['filename'] = askopenfilename(**opts)
    try:
        subprocess.run(['pdftotext', returnedValue['filename'], '-raw'], check = True)
    except (TypeError, subprocess.CalledProcessError) as e:
        messagebox.showerror("Null error", "No file selected")
    if sys.platform == "linux" or sys.platform == "linux2" or sys.platform == "darwin":
        label = returnedValue['filename'].split('/')
        file2['file2'] = label[len(label)-1]
    else:
        label = returnedValue['filename'].split('\')
        file2['file2'] = label[len(label)-1]

    L.insert(0, label[len(label)-1])

def trello():
    with open(returnedValue['filename'], 'r', encoding='utf8', errors='ignore') as f:
        content = f.readlines()
    content = [x.strip() for x in content]
    for line in content:
        print(line)


opts = {}
opts['filetypes'] = [('Portable Document Format','.pdf'),('all files','.*')]
opts['defaultextension'] = '.pdf'
opts['title'] = 'Select File'
opts['initialdir'] = [os.path.expanduser('~/')]

returnedValue = {}
returnedValue['filename'] = ""
file2 = {}
file2['file2'] = ""
root = tkinter.Tk()

B = Button(root, text = "Convert PDF", command = chooser)
B.pack()

F = Frame(root)

La = Label(F, text="PDFs Converted:")
La.pack()

S = Scrollbar(F)
S.pack(side=tkinter.RIGHT, fill=tkinter.Y)

L = Listbox(F, height=5, yscrollcommand=S.set)
L.pack()

S.config(command=L.yview)

F.pack()

Bue = Button(root, text="Send to Trello", command = trello)
Bue.pack()

root.geometry('{}x{}'.format(500, 500))
root.attributes("-topmost", True)
root.wm_title("PDF Chooser")
root.mainloop()

这是我在 open() 函数中不使用 errors='ignore' 时出现的错误：

Exception in Tkinter callback
Traceback (most recent call last):
  File "/usr/lib/python3.6/tkinter/__init__.py", line 1702, in __call__
    return self.func(*args)
  File "./pdftotextCVM.py", line 34, in trello
    content = f.readlines()
  File "/usr/lib/python3.6/codecs.py", line 321, in decode
    (result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xff in position 11:     invalid start byte

而 here 是我使用 errors=ignore 时得到的结果。最后的粘贴可以追溯到我的 Ubuntu 终端历史记录，所以可能还有更多，但你明白了。旁注：如果你不知道，我正在使用 Python 3.6.

Answer 1

向下滚动，越过二进制垃圾，从 errors=ignore 输出中，我看到：

22 0 obj
<<
/Type /Font
/Subtype /Type0
/BaseFont /OXSVSB+TimesNewRoman/Encoding /Identity-H
/ToUnicode 23 0 R
/DescendantFonts[ 24 0 R ]
>>

这些是 PDF 说明。好像输入了.pdf。正在打开文件，而不是输出 .txt 文件。

trello() 函数可能需要在打开文件之前将扩展名从 .pdf 更改为 .txt。

PDF转换后文件打开奇怪

File opening weird after PDF conversion

python

pdf

python-3.6