使用PDFMiner处理单色页面

Question

我有一些PDF文档，我无法使用PyPDF仅使用PDFMiner提取文本。以下代码可以正常工作以从PDF中提取所有文本，它会遍历整个文档，然后返回所有文本。 有没有办法只能使用PDF的某些页面？ 我拥有的PDF格式都是2000-3000多长，我只需要每隔一页就完成一次。

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

def convert_pdf_to_txt(path): 
    rsrcmgr = PDFResourceManager() 
    retstr = StringIO() 
    codec = 'utf-8' 
    laparams = LAParams() 
    device = TextConverter(rsrcmgr, retstr, codec=codec,laparams=laparams) 
    fp = file(path, 'rb') 
    interpreter = PDFPageInterpreter(rsrcmgr, device) 
    password = "" 
    maxpages = 0 
    caching = True 
    pagenos=set() 

    for page in PDFPage.get_pages(fp, pagenos, maxpages=maxpages, password=password,caching=caching, check_extractable=True): 
     interpreter.process_page(page) 

    text = retstr.getvalue() 

    fp.close() 
    device.close() 
    retstr.close() 
    return text 

Answer 1

你不能使用enumerate获得页面数和同时通过所有页面遍历网页的内容？如果您只需要每隔一页，请使用模数。如果您只想要特定页面，请使用范围。

例子：

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

def convert_pdf_to_txt(path): 
    rsrcmgr = PDFResourceManager() 
    retstr = StringIO() 
    codec = 'utf-8' 
    laparams = LAParams() 
    device = TextConverter(rsrcmgr, retstr, codec=codec,laparams=laparams) 
    fp = file(path, 'rb') 
    interpreter = PDFPageInterpreter(rsrcmgr, device) 
    password = "" 
    maxpages = 0 
    caching = True 
    pagenos=set() 

    for pagenumber, page in enumerate(PDFPage.get_pages(fp, pagenos, maxpages=maxpages, password=password,caching=caching, check_extractable=True)): 
     print pagenumber 
     if pagenumber % 2 == 0: 
      print("even page number") 
      interpreter.process_page(page) 
     else: 
      print("odd page number") 
     if 5 <= pagenumber <= 10: 
      print("pages 5 to 10") 

    text = retstr.getvalue() 

    fp.close() 
    device.close() 
    retstr.close() 
    return text