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首先，我使用的是 Python 3.5.1（32 位版本），我编写了以下程序，使用 PyPDF2 和 reportlab 在我的 pdf 文件的所有页面上添加页码：

#import modules
from os import listdir
from PyPDF2 import PdfFileWriter, PdfFileReader
import io
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import A4
#initial values of variable declarations
PDFlist=[]
X_value=460
Y_value=820
#Make a list of al files in de directory
filelist = listdir()
#Make a list of all pdf files in the directory
for i in range(0,len(filelist)):
    filename=filelist[i]
    for j in range(0,len(filename)):
        char=filename[j]
        if char=='.':
            extension=filename[j+1:j+4]
            if extension=='pdf':
                PDFlist.append(filename)
        j=j+1
    i=i+1
# Give the horizontal position for the page number (Enter = use default value of 480)
User = input('Give horizontal position page number (ENTER = default 460): ')
if User != "":
    X_value=int(User)
# Give the vertical position for the page number (Enter = use default value of 820)
User = input('Give horizontal position page number (ENTER = default 820): ')
if User != "":
    Y_value=int(User)

for i in range(0,len(PDFlist)):
    filename=PDFlist[i]

    # read the PDF
    existing_pdf = PdfFileReader(open(filename, "rb"))
    print("File: "+filename)
    # count the number of pages
    number_of_pages = existing_pdf.getNumPages()
    print("Number of pages detected:"+str(number_of_pages))
    output = PdfFileWriter()

    for k in range(0,number_of_pages):
        packet = io.BytesIO()

        # create a new PDF with Reportlab
        can = canvas.Canvas(packet, pagesize=A4)
        Pagenumber=" Page "+str(k+1)+"/"+str(number_of_pages)
        # we first make a white rectangle to cover any existing text in the pdf
        can.setFillColorRGB(1,1,1)
        can.setStrokeColorRGB(1,1,1)
        can.rect(X_value-10,Y_value-5,120,20,fill=1)
        # set the font and size
        can.setFont("Helvetica",14)
        # choose color of page numbers (red)
        can.setFillColorRGB(1,0,0)
        can.drawString(X_value, Y_value, Pagenumber)
        can.save()
        print(Pagenumber)

        #move to the beginning of the StringIO buffer
        packet.seek(0)
        new_pdf = PdfFileReader(packet)
        # add the "watermark" (which is the new pdf) on the existing page
        page = existing_pdf.getPage(k)
        page.mergePage(new_pdf.getPage(0))
        output.addPage(page)
        k=k+1
    # finally, write "output" to a real file

    ResultPDF="Output/"+filename
    outputStream = open(ResultPDF, "wb")
    output.write(outputStream)
    outputStream.close()
    i=i+1

该程序适用于相当多的 PDF 文件（尽管有时会生成警告，如 ' PdfReadWarning: Superfluous whitespace found in object header b'16' b'0' [pdf.py:1666]' 但生成的输出文件对我来说没问题）。但是，该程序无法处理某些 PDF 文件，尽管这些文件在我的 Adob​​e Acrobat 中是完全可读和可编辑的。我的印象是，错误主要出现在已扫描的 PDF 文件上，但并非全部出现（我还对未生成任何错误的扫描 PDF 文件进行了编号）。我收到以下错误消息（前 8 行是我自己的打印命令的结果）：

File: Scanned file.pdf
Number of pages detected:6
 Page 1/6
 Page 2/6
 Page 3/6
 Page 4/6
 Page 5/6
 Page 6/6
PdfReadWarning: Object 25 1 not defined. [pdf.py:1629]
Traceback (most recent call last):
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\Sourcecode\PDFPager.py", line 83, in <module>
    output.write(outputStream)
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 482, in write
    self._sweepIndirectReferences(externalReferenceMap, self._root)
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 571, in _sweepIndirectReferences
    self._sweepIndirectReferences(externMap, realdata)
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 547, in _sweepIndirectReferences
    value = self._sweepIndirectReferences(externMap, value)
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 571, in _sweepIndirectReferences
    self._sweepIndirectReferences(externMap, realdata)
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 547, in _sweepIndirectReferences
    value = self._sweepIndirectReferences(externMap, value)
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 556, in _sweepIndirectReferences
    value = self._sweepIndirectReferences(externMap, data[i])
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 571, in _sweepIndirectReferences
    self._sweepIndirectReferences(externMap, realdata)
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 547, in _sweepIndirectReferences
    value = self._sweepIndirectReferences(externMap, value)
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 556, in _sweepIndirectReferences
    value = self._sweepIndirectReferences(externMap, data[i])
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 577, in _sweepIndirectReferences
    newobj = data.pdf.getObject(data)
  File "C:\Users\User\AppData\Local\Programs\Python\Python35-32\lib\site-packages\PyPDF2\pdf.py", line 1631, in getObject
    raise utils.PdfReadError("Could not find object.")
PyPDF2.utils.PdfReadError: Could not find object.

显然，这些页面与由 reportlab 创建的 PDF 合并（参见第 6/6 页的行），但最终 PyPDF2 无法生成输出 PDF 文件（我得到一个不可读的 0 字节输出文件）。有人可以阐明如何解决这个问题吗？我搜索了互联网，但无法真正找到答案。

4

4 回答 4

6

在 pdf.py 上进行以下更改：

在 pdf 的第 1633 行。py （这意味着取消注释 if self.strict）

    if self.strict:
        raise utils.PdfReadError("Could not find object.")

并在 pdf.py 上的第 501 行进行以下更改（添加尝试，除了块）

    try:
        obj.writeToStream(stream, key)
        stream.write(b_("\nendobj\n"))
    except:
        pass

干杯。

于 2018-10-07T10:49:45.377 回答
6

使用“strict = false”让事情对我有用。

from PyPDF2 import PdfFileMerger

pdfs = [r'file 1.pdf', r'file 2.pdf']

merger = PdfFileMerger(strict=False)

for pdf in pdfs:
    merger.append(pdf)

merger.write(r"thanks mate.pdf")
于 2019-06-10T22:56:47.757 回答
0

Here is my solution. Try to write the file into a dummy ByteIO stream to check whether it is broken.

    try:
        reader = PdfFileReader(input_file)
        print("Opening '{}', pages={}".format(file_path, reader.getNumPages()))
        # Try to write it into an dummy ByteIO stream to check whether pdf is broken
        writer = PdfFileWriter()
        writer.addPage(reader.getPage(0))
        writer.write(io.BytesIO())
    except PdfReadError:
        print("Error reading '{}".format(file_path))
        continue
于 2020-07-05T08:35:29.380 回答
0

我刚刚遇到了与 pypdf2 相同的错误。这是与pdf版本有关的问题

只需使用pikepdf包，然后问题就消失了。

你可以在这里找到文档

于 2021-11-23T07:03:13.480 回答