根据大纲分割pdf

时间:2009-12-16 23:00:08

标签: python pdf pypdf

我想使用pyPdf基于轮廓分割pdf文件,其中轮廓中的每个目的地引用pdf中的不同页面。

示例大纲:

main       --> points to page 1
  sect1    --> points to page 1
  sect2    --> points to page 15
  sect3    --> points to page 22

在pyPdf中很容易迭代文档的每个页面或文档大纲中的每个目标;但是,我无法弄清楚如何获得目的地所在的页码。

有人知道如何找到大纲中每个目的地的参考页码吗?

4 个答案:

答案 0 :(得分:7)

我明白了:

class Darrell(pyPdf.PdfFileReader):

    def getDestinationPageNumbers(self):
        def _setup_outline_page_ids(outline, _result=None):
            if _result is None:
                _result = {}
            for obj in outline:
                if isinstance(obj, pyPdf.pdf.Destination):
                    _result[(id(obj), obj.title)] = obj.page.idnum
                elif isinstance(obj, list):
                    _setup_outline_page_ids(obj, _result)
            return _result

        def _setup_page_id_to_num(pages=None, _result=None, _num_pages=None):
            if _result is None:
                _result = {}
            if pages is None:
                _num_pages = []
                pages = self.trailer["/Root"].getObject()["/Pages"].getObject()
            t = pages["/Type"]
            if t == "/Pages":
                for page in pages["/Kids"]:
                    _result[page.idnum] = len(_num_pages)
                    _setup_page_id_to_num(page.getObject(), _result, _num_pages)
            elif t == "/Page":
                _num_pages.append(1)
            return _result

        outline_page_ids = _setup_outline_page_ids(self.getOutlines())
        page_id_to_page_numbers = _setup_page_id_to_num()

        result = {}
        for (_, title), page_idnum in outline_page_ids.iteritems():
            result[title] = page_id_to_page_numbers.get(page_idnum, '???')
        return result

pdf = Darrell(open(PATH-TO-PDF, 'rb'))
template = '%-5s  %s'
print template % ('page', 'title')
for p,t in sorted([(v,k) for k,v in pdf.getDestinationPageNumbers().iteritems()]):
    print template % (p+1,t)

答案 1 :(得分:1)

Darrell的类可以稍微修改以生成pdf的多级目录(在pdftk工具箱中以pdftoc的方式。)

我的修改为_setup_page_id_to_num添加了一个参数,一个整数“level”,默认为1.每次调用都会增加该级别。我们不存储结果中的页码,而是存储一对页码和级别。使用返回的结果时,应该应用适当的修改。

我正在使用它来实现“PDF Hacks”基于浏览器的页面一次性文档查看器,其侧边栏目录反映了LaTeX部分,子部分等书签。我正在开发一个共享系统,其中无法安装pdftk但python可用。

答案 2 :(得分:0)

这正是我所寻找的。 Darrell对PdfFileReader的补充应该是PyPDF2的一部分。

我写了一个小方法,使用PyPDF2和sejda-console通过书签分割PDF。在我的情况下,有几个我想要保持在一起的1级部分。这个脚本允许我这样做,并为结果文件提供有意义的名称。

import operator
import os
import subprocess
import sys
import time

import PyPDF2 as pyPdf

# need to have sejda-console installed
# change this to point to your installation
sejda = 'C:\\sejda-console-1.0.0.M2\\bin\\sejda-console.bat'

class Darrell(pyPdf.PdfFileReader):
    ...

if __name__ == '__main__':
    t0= time.time()

    # get the name of the file to split as a command line arg
    pdfname = sys.argv[1]

    # open up the pdf
    pdf = Darrell(open(pdfname, 'rb'))

    # build list of (pagenumbers, newFileNames)
    splitlist = [(1,'FrontMatter')] # Customize name of first section

    template = '%-5s  %s'
    print template % ('Page', 'Title')
    print '-'*72
    for t,p in sorted(pdf.getDestinationPageNumbers().iteritems(),
                      key=operator.itemgetter(1)):

        # Customize this to get it to split where you want
        if t.startswith('Chapter') or \
           t.startswith('Preface') or \
           t.startswith('References'):

            print template % (p+1, t)

            # this customizes how files are renamed
            new = t.replace('Chapter ', 'Chapter')\
                   .replace(':  ', '-')\
                   .replace(': ', '-')\
                   .replace(' ', '_')
            splitlist.append((p+1, new))

    # call sejda tools and split document
    call = sejda
    call += ' splitbypages'
    call += ' -f "%s"'%pdfname
    call += ' -o ./'
    call += ' -n '
    call += ' '.join([str(p) for p,t in splitlist[1:]])
    print '\n', call
    subprocess.call(call)
    print '\nsejda-console has completed.\n\n'

    # rename the split files
    for p,t in splitlist:
        old ='./%i_'%p + pdfname
        new = './' + t + '.pdf'
        print 'renaming "%s"\n      to "%s"...'%(old, new),

        try:
            os.remove(new)
        except OSError:
            pass

        try:
            os.rename(old, new)
            print' succeeded.\n'
        except:
            print' failed.\n'

    print '\ndone. Spliting took %.2f seconds'%(time.time() - t0)

答案 3 :(得分:0)

对@darrell类的小更新,以便能够解析UTF-8轮廓,我将其作为答案发布,因为评论很难阅读。

问题在于pyPdf.pdf.Destination.title,可能会以两种方式返回:

  • pyPdf.generic.TextStringObject
  • pyPdf.generic.ByteStringObject

以便来自_setup_outline_page_ids()函数的输出还为title对象返回两种不同的类型,如果大纲标题包含除ASCII之外的任何内容,则会失败UnicodeDecodeError

我添加了此代码来解决问题:

if isinstance(title, pyPdf.generic.TextStringObject):
    title = title.encode('utf-8')
全班学生:

class PdfOutline(pyPdf.PdfFileReader):

    def getDestinationPageNumbers(self):

        def _setup_outline_page_ids(outline, _result=None):
            if _result is None:
                _result = {}
            for obj in outline:
                if isinstance(obj, pyPdf.pdf.Destination):
                    _result[(id(obj), obj.title)] = obj.page.idnum
                elif isinstance(obj, list):
                    _setup_outline_page_ids(obj, _result)
            return _result

        def _setup_page_id_to_num(pages=None, _result=None, _num_pages=None):
            if _result is None:
                _result = {}
            if pages is None:
                _num_pages = []
                pages = self.trailer["/Root"].getObject()["/Pages"].getObject()
            t = pages["/Type"]
            if t == "/Pages":
                for page in pages["/Kids"]:
                    _result[page.idnum] = len(_num_pages)
                    _setup_page_id_to_num(page.getObject(), _result, _num_pages)
            elif t == "/Page":
                _num_pages.append(1)
            return _result

        outline_page_ids = _setup_outline_page_ids(self.getOutlines())
        page_id_to_page_numbers = _setup_page_id_to_num()

        result = {}
        for (_, title), page_idnum in outline_page_ids.iteritems():
            if isinstance(title, pyPdf.generic.TextStringObject):
                title = title.encode('utf-8')
            result[title] = page_id_to_page_numbers.get(page_idnum, '???')
        return result