用于将PDF转换为文本的Python模块[关闭]-Java 学习之路

350

哪些是将PDF文件转换为文本的最佳Python模块？

13 回答

133
试试PDFMiner . 它可以从PDF文件中提取HTML，SGML或“Tagged PDF”格式的文本 .

http://www.unixuser.org/~euske/python/pdfminer/index.html

Tagged PDF格式似乎是最干净的，剥离XML标签只留下裸文本 .

Python 3版本可在以下位置获得：
- https://github.com/pdfminer/pdfminer.six
回复于 2024-05-02T15:48:21+08:00

自codeape发布以来，PDFMiner包已更改 .

EDIT (again):

PDFMiner已在版本 20100213 中再次更新

您可以使用以下内容检查已安装的版本：

>>> import pdfminer
>>> pdfminer.__version__
'20100213'

这是更新版本（包含我更改/添加内容的评论）：

def pdf_to_csv(filename):
    from cStringIO import StringIO  #<-- added so you can copy/paste this to try it
    from pdfminer.converter import LTTextItem, TextConverter
    from pdfminer.pdfparser import PDFDocument, PDFParser
    from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter

    class CsvConverter(TextConverter):
        def __init__(self, *args, **kwargs):
            TextConverter.__init__(self, *args, **kwargs)

        def end_page(self, i):
            from collections import defaultdict
            lines = defaultdict(lambda : {})
            for child in self.cur_item.objs:
                if isinstance(child, LTTextItem):
                    (_,_,x,y) = child.bbox                   #<-- changed
                    line = lines[int(-y)]
                    line[x] = child.text.encode(self.codec)  #<-- changed

            for y in sorted(lines.keys()):
                line = lines[y]
                self.outfp.write(";".join(line[x] for x in sorted(line.keys())))
                self.outfp.write("\n")

    # ... the following part of the code is a remix of the 
    # convert() function in the pdfminer/tools/pdf2text module
    rsrc = PDFResourceManager()
    outfp = StringIO()
    device = CsvConverter(rsrc, outfp, codec="utf-8")  #<-- changed 
        # becuase my test documents are utf-8 (note: utf-8 is the default codec)

    doc = PDFDocument()
    fp = open(filename, 'rb')
    parser = PDFParser(fp)       #<-- changed
    parser.set_document(doc)     #<-- added
    doc.set_parser(parser)       #<-- added
    doc.initialize('')

    interpreter = PDFPageInterpreter(rsrc, device)

    for i, page in enumerate(doc.get_pages()):
        outfp.write("START PAGE %d\n" % i)
        interpreter.process_page(page)
        outfp.write("END PAGE %d\n" % i)

    device.close()
    fp.close()

    return outfp.getvalue()

Edit (yet again):

以下是pypi， 20100619p1 中最新版本的更新 . 简而言之，我将 LTTextItem 替换为 LTChar 并将LAParams实例传递给CsvConverter构造函数 .

def pdf_to_csv(filename):
    from cStringIO import StringIO  
    from pdfminer.converter import LTChar, TextConverter    #<-- changed
    from pdfminer.layout import LAParams
    from pdfminer.pdfparser import PDFDocument, PDFParser
    from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter

    class CsvConverter(TextConverter):
        def __init__(self, *args, **kwargs):
            TextConverter.__init__(self, *args, **kwargs)

        def end_page(self, i):
            from collections import defaultdict
            lines = defaultdict(lambda : {})
            for child in self.cur_item.objs:
                if isinstance(child, LTChar):               #<-- changed
                    (_,_,x,y) = child.bbox                   
                    line = lines[int(-y)]
                    line[x] = child.text.encode(self.codec)

            for y in sorted(lines.keys()):
                line = lines[y]
                self.outfp.write(";".join(line[x] for x in sorted(line.keys())))
                self.outfp.write("\n")

    # ... the following part of the code is a remix of the 
    # convert() function in the pdfminer/tools/pdf2text module
    rsrc = PDFResourceManager()
    outfp = StringIO()
    device = CsvConverter(rsrc, outfp, codec="utf-8", laparams=LAParams())  #<-- changed
        # becuase my test documents are utf-8 (note: utf-8 is the default codec)

    doc = PDFDocument()
    fp = open(filename, 'rb')
    parser = PDFParser(fp)       
    parser.set_document(doc)     
    doc.set_parser(parser)       
    doc.initialize('')

    interpreter = PDFPageInterpreter(rsrc, device)

    for i, page in enumerate(doc.get_pages()):
        outfp.write("START PAGE %d\n" % i)
        if page is not None:
            interpreter.process_page(page)
        outfp.write("END PAGE %d\n" % i)

    device.close()
    fp.close()

    return outfp.getvalue()

EDIT (one more time):

更新版本 20110515 （感谢Oeufcoque Penteano！）：

def pdf_to_csv(filename):
    from cStringIO import StringIO  
    from pdfminer.converter import LTChar, TextConverter
    from pdfminer.layout import LAParams
    from pdfminer.pdfparser import PDFDocument, PDFParser
    from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter

    class CsvConverter(TextConverter):
        def __init__(self, *args, **kwargs):
            TextConverter.__init__(self, *args, **kwargs)

        def end_page(self, i):
            from collections import defaultdict
            lines = defaultdict(lambda : {})
            for child in self.cur_item._objs:                #<-- changed
                if isinstance(child, LTChar):
                    (_,_,x,y) = child.bbox                   
                    line = lines[int(-y)]
                    line[x] = child._text.encode(self.codec) #<-- changed

            for y in sorted(lines.keys()):
                line = lines[y]
                self.outfp.write(";".join(line[x] for x in sorted(line.keys())))
                self.outfp.write("\n")

    # ... the following part of the code is a remix of the 
    # convert() function in the pdfminer/tools/pdf2text module
    rsrc = PDFResourceManager()
    outfp = StringIO()
    device = CsvConverter(rsrc, outfp, codec="utf-8", laparams=LAParams())
        # becuase my test documents are utf-8 (note: utf-8 is the default codec)

    doc = PDFDocument()
    fp = open(filename, 'rb')
    parser = PDFParser(fp)       
    parser.set_document(doc)     
    doc.set_parser(parser)       
    doc.initialize('')

    interpreter = PDFPageInterpreter(rsrc, device)

    for i, page in enumerate(doc.get_pages()):
        outfp.write("START PAGE %d\n" % i)
        if page is not None:
            interpreter.process_page(page)
        outfp.write("END PAGE %d\n" % i)

    device.close()
    fp.close()

    return outfp.getvalue()

回复于 2024-05-02T15:48:21+08:00

由于这些解决方案都没有支持最新版本的PDFMiner，因此我编写了一个简单的解决方案，它将使用PDFMiner返回pdf文本 . 这适用于那些因 process_pdf 而导致导入错误的人

import sys
from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter
from pdfminer.pdfpage import PDFPage
from pdfminer.converter import XMLConverter, HTMLConverter, TextConverter
from pdfminer.layout import LAParams
from cStringIO import StringIO

def pdfparser(data):

    fp = file(data, 'rb')
    rsrcmgr = PDFResourceManager()
    retstr = StringIO()
    codec = 'utf-8'
    laparams = LAParams()
    device = TextConverter(rsrcmgr, retstr, codec=codec, laparams=laparams)
    # Create a PDF interpreter object.
    interpreter = PDFPageInterpreter(rsrcmgr, device)
    # Process each page contained in the document.

    for page in PDFPage.get_pages(fp):
        interpreter.process_page(page)
        data =  retstr.getvalue()

    print data

if __name__ == '__main__':
    pdfparser(sys.argv[1])

请参阅以下适用于Python 3的代码：

import sys
from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter
from pdfminer.pdfpage import PDFPage
from pdfminer.converter import XMLConverter, HTMLConverter, TextConverter
from pdfminer.layout import LAParams
import io

def pdfparser(data):

    fp = open(data, 'rb')
    rsrcmgr = PDFResourceManager()
    retstr = io.StringIO()
    codec = 'utf-8'
    laparams = LAParams()
    device = TextConverter(rsrcmgr, retstr, codec=codec, laparams=laparams)
    # Create a PDF interpreter object.
    interpreter = PDFPageInterpreter(rsrcmgr, device)
    # Process each page contained in the document.

    for page in PDFPage.get_pages(fp):
        interpreter.process_page(page)
        data =  retstr.getvalue()

    print(data)

if __name__ == '__main__':
    pdfparser(sys.argv[1])

回复于 2024-05-02T15:48:21+08:00

5
pyPDF工作正常（假设您正在处理格式良好的PDF） . 如果你想要的只是文本（带空格），你可以这样做：
```
import pyPdf
pdf = pyPdf.PdfFileReader(open(filename, "rb"))
for page in pdf.pages:
    print page.extractText()
```
您还可以轻松访问元数据，图像数据等 .

extractText代码注释中的注释：

按照内容流中提供的顺序查找所有文本绘制命令，然后提取文本 . 这适用于某些PDF文件，但对其他PDF文件效果不佳，具体取决于所使用的生成器 . 这将在未来得到完善 . 不要依赖于此函数的文本顺序，因为如果此功能变得更复杂，它将会改变 .

这是否是一个问题取决于你正在对文本做什么（例如，如果顺序无关紧要，没关系，或者如果生成器按照它将显示的顺序将文本添加到流中，那很好） . 我在日常使用中有pyPdf提取代码，没有任何问题 .
回复于 2024-05-02T15:48:21+08:00
53

Pdftotext一个开源程序（Xpdf的一部分），你可以从python调用它（不是你要求但可能有用） . 我没有遇到任何问题 . 我认为谷歌在谷歌桌面使用它 .

回复于 2024-05-02T15:48:21+08:00

您也可以很容易地将pdfminer用作库 . 您可以访问pdf的内容模型，并可以创建自己的文本提取 . 我这样做是为了使用下面的代码将pdf内容转换为分号分隔文本 .

该函数根据y和x坐标简单地对TextItem内容对象进行排序，并输出具有相同y坐标的项作为一个文本行，将同一行上的对象与';'分开字符 .

使用这种方法，我能够从pdf中提取文本，其他工具无法提取适合进一步解析的内容 . 我尝试过的其他工具包括pdftotext，ps2ascii和在线工具pdftextonline.com .

pdfminer是pdf-scraping的宝贵工具 .

def pdf_to_csv(filename):
    from pdflib.page import TextItem, TextConverter
    from pdflib.pdfparser import PDFDocument, PDFParser
    from pdflib.pdfinterp import PDFResourceManager, PDFPageInterpreter

    class CsvConverter(TextConverter):
        def __init__(self, *args, **kwargs):
            TextConverter.__init__(self, *args, **kwargs)

        def end_page(self, i):
            from collections import defaultdict
            lines = defaultdict(lambda : {})
            for child in self.cur_item.objs:
                if isinstance(child, TextItem):
                    (_,_,x,y) = child.bbox
                    line = lines[int(-y)]
                    line[x] = child.text

            for y in sorted(lines.keys()):
                line = lines[y]
                self.outfp.write(";".join(line[x] for x in sorted(line.keys())))
                self.outfp.write("\n")

    # ... the following part of the code is a remix of the 
    # convert() function in the pdfminer/tools/pdf2text module
    rsrc = PDFResourceManager()
    outfp = StringIO()
    device = CsvConverter(rsrc, outfp, "ascii")

    doc = PDFDocument()
    fp = open(filename, 'rb')
    parser = PDFParser(doc, fp)
    doc.initialize('')

    interpreter = PDFPageInterpreter(rsrc, device)

    for i, page in enumerate(doc.get_pages()):
        outfp.write("START PAGE %d\n" % i)
        interpreter.process_page(page)
        outfp.write("END PAGE %d\n" % i)

    device.close()
    fp.close()

    return outfp.getvalue()

UPDATE ：

上面的代码是针对旧版本的API编写的，请参阅下面的评论 .

回复于 2024-05-02T15:48:21+08:00

slate是一个项目，它使得从库中使用PDFMiner变得非常简单：

>>> with open('example.pdf') as f:
...    doc = slate.PDF(f)
...
>>> doc
[..., ..., ...]
>>> doc[1]
'Text from page 2...'

回复于 2024-05-02T15:48:21+08:00

我需要将特定的PDF转换为python模块中的纯文本 . 我使用了PDFMiner 20110515，在阅读了他们的pdf2txt.py工具后，我写了这个简单的片段：

from cStringIO import StringIO
from pdfminer.pdfinterp import PDFResourceManager, process_pdf
from pdfminer.converter import TextConverter
from pdfminer.layout import LAParams

def to_txt(pdf_path):
    input_ = file(pdf_path, 'rb')
    output = StringIO()

    manager = PDFResourceManager()
    converter = TextConverter(manager, output, laparams=LAParams())
    process_pdf(manager, converter, input_)

    return output.getvalue()

回复于 2024-05-02T15:48:21+08:00

重新利用pdfminer附带的pdf2txt.py代码;你可以创建一个函数来获取pdf的路径;可选地，outtype（txt | html | xml | tag）和opts类似于命令行pdf2txt {' - o'：'/ path / to / outfile.txt'...} . 默认情况下，您可以调用：

convert_pdf(path)

将创建一个文本文件，将文件系统中的兄弟文件创建为原始pdf .

def convert_pdf(path, outtype='txt', opts={}):
    import sys
    from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter, process_pdf
    from pdfminer.converter import XMLConverter, HTMLConverter, TextConverter, TagExtractor
    from pdfminer.layout import LAParams
    from pdfminer.pdfparser import PDFDocument, PDFParser
    from pdfminer.pdfdevice import PDFDevice
    from pdfminer.cmapdb import CMapDB

    outfile = path[:-3] + outtype
    outdir = '/'.join(path.split('/')[:-1])

    debug = 0
    # input option
    password = ''
    pagenos = set()
    maxpages = 0
    # output option
    codec = 'utf-8'
    pageno = 1
    scale = 1
    showpageno = True
    laparams = LAParams()
    for (k, v) in opts:
        if k == '-d': debug += 1
        elif k == '-p': pagenos.update( int(x)-1 for x in v.split(',') )
        elif k == '-m': maxpages = int(v)
        elif k == '-P': password = v
        elif k == '-o': outfile = v
        elif k == '-n': laparams = None
        elif k == '-A': laparams.all_texts = True
        elif k == '-D': laparams.writing_mode = v
        elif k == '-M': laparams.char_margin = float(v)
        elif k == '-L': laparams.line_margin = float(v)
        elif k == '-W': laparams.word_margin = float(v)
        elif k == '-O': outdir = v
        elif k == '-t': outtype = v
        elif k == '-c': codec = v
        elif k == '-s': scale = float(v)
    #
    CMapDB.debug = debug
    PDFResourceManager.debug = debug
    PDFDocument.debug = debug
    PDFParser.debug = debug
    PDFPageInterpreter.debug = debug
    PDFDevice.debug = debug
    #
    rsrcmgr = PDFResourceManager()
    if not outtype:
        outtype = 'txt'
        if outfile:
            if outfile.endswith('.htm') or outfile.endswith('.html'):
                outtype = 'html'
            elif outfile.endswith('.xml'):
                outtype = 'xml'
            elif outfile.endswith('.tag'):
                outtype = 'tag'
    if outfile:
        outfp = file(outfile, 'w')
    else:
        outfp = sys.stdout
    if outtype == 'txt':
        device = TextConverter(rsrcmgr, outfp, codec=codec, laparams=laparams)
    elif outtype == 'xml':
        device = XMLConverter(rsrcmgr, outfp, codec=codec, laparams=laparams, outdir=outdir)
    elif outtype == 'html':
        device = HTMLConverter(rsrcmgr, outfp, codec=codec, scale=scale, laparams=laparams, outdir=outdir)
    elif outtype == 'tag':
        device = TagExtractor(rsrcmgr, outfp, codec=codec)
    else:
        return usage()

    fp = file(path, 'rb')
    process_pdf(rsrcmgr, device, fp, pagenos, maxpages=maxpages, password=password)
    fp.close()
    device.close()

    outfp.close()
    return

回复于 2024-05-02T15:48:21+08:00

17

此外还有PDFTextStream这是一个商业Java库，也可以从Python中使用 .

回复于 2024-05-02T15:48:21+08:00
42

我使用了带有'-xml'参数的pdftohtml，使用subprocess.Popen（）读取结果，它将为pdf中的每个“文本片段”提供x坐标，y坐标，宽度，高度和字体 . 我认为这也是'evince'可能使用的，因为同样的错误信息会喷出来 .

如果您需要处理柱状数据，那么由于您必须发明适合您的pdf文件的算法，它会稍微复杂一些 . 该问题是制作PDF文件的程序并不一定要以任何逻辑格式布局文本 . 您可以尝试简单的排序算法，它有时会起作用，但是可能会有很少的“落后者”和“流浪者”，文本片段没有按照您认为的顺序放置......因此您必须具有创造性 .

我花了大约5个小时来找出我正在制作的pdf . 但它现在效果很好 . 祝好运 .

回复于 2024-05-02T15:48:21+08:00
1

PDFminer在我试过的pdf文件的每一页上都给了我一行[第1页，共7页] .

到目前为止，我得到的最佳答案是pdftoipe，或者它基于Xpdf的c代码 .

有关pdftoipe的输出结果，请参阅my question .

回复于 2024-05-02T15:48:21+08:00
127

今天找到了解决方案 . 对我来说很棒 . 甚至将PDF页面渲染为PNG图像 . http://www.swftools.org/gfx_tutorial.html

回复于 2024-05-02T15:48:21+08:00

用于将PDF转换为文本的Python模块[关闭]

13 回答

相关问题