How to extract text and text coordinates from a PDF file?
Newlines are converted to underscores in final output. This is the minimal working solution that I found.
from pdfminer.pdfparser import PDFParserfrom pdfminer.pdfdocument import PDFDocumentfrom pdfminer.pdfpage import PDFPagefrom pdfminer.pdfpage import PDFTextExtractionNotAllowedfrom pdfminer.pdfinterp import PDFResourceManagerfrom pdfminer.pdfinterp import PDFPageInterpreterfrom pdfminer.pdfdevice import PDFDevicefrom pdfminer.layout import LAParamsfrom pdfminer.converter import PDFPageAggregatorimport pdfminer# Open a PDF file.fp = open('/Users/me/Downloads/test.pdf', 'rb')# Create a PDF parser object associated with the file object.parser = PDFParser(fp)# Create a PDF document object that stores the document structure.# Password for initialization as 2nd parameterdocument = PDFDocument(parser)# Check if the document allows text extraction. If not, abort.if not document.is_extractable: raise PDFTextExtractionNotAllowed# Create a PDF resource manager object that stores shared resources.rsrcmgr = PDFResourceManager()# Create a PDF device object.device = PDFDevice(rsrcmgr)# BEGIN LAYOUT ANALYSIS# Set parameters for analysis.laparams = LAParams()# Create a PDF page aggregator object.device = PDFPageAggregator(rsrcmgr, laparams=laparams)# Create a PDF interpreter object.interpreter = PDFPageInterpreter(rsrcmgr, device)def parse_obj(lt_objs): # loop over the object list for obj in lt_objs: # if it's a textbox, print text and location if isinstance(obj, pdfminer.layout.LTTextBoxHorizontal): print "%6d, %6d, %s" % (obj.bbox[0], obj.bbox[1], obj.get_text().replace('\n', '_')) # if it's a container, recurse elif isinstance(obj, pdfminer.layout.LTFigure): parse_obj(obj._objs)# loop over all pages in the documentfor page in PDFPage.create_pages(document): # read the page into a layout object interpreter.process_page(page) layout = device.get_result() # extract text from this object parse_obj(layout._objs)
Here's a copy-and-paste-ready example that lists the top-left corners of every block of text in a PDF, and which I think should work for any PDF that doesn't include "Form XObjects" that have text in them:
from pdfminer.layout import LAParams, LTTextBoxfrom pdfminer.pdfpage import PDFPagefrom pdfminer.pdfinterp import PDFResourceManagerfrom pdfminer.pdfinterp import PDFPageInterpreterfrom pdfminer.converter import PDFPageAggregatorfp = open('yourpdf.pdf', 'rb')rsrcmgr = PDFResourceManager()laparams = LAParams()device = PDFPageAggregator(rsrcmgr, laparams=laparams)interpreter = PDFPageInterpreter(rsrcmgr, device)pages = PDFPage.get_pages(fp)for page in pages: print('Processing next page...') interpreter.process_page(page) layout = device.get_result() for lobj in layout: if isinstance(lobj, LTTextBox): x, y, text = lobj.bbox[0], lobj.bbox[3], lobj.get_text() print('At %r is text: %s' % ((x, y), text))
The code above is based upon the Performing Layout Analysis example in the PDFMiner docs, plus the examples by pnj (https://stackoverflow.com/a/22898159/1709587) and Matt Swain (https://stackoverflow.com/a/25262470/1709587). There are a couple of changes I've made from these previous examples:
- I use
PDFPage.get_pages()
, which is a shorthand for creating a document, checking itis_extractable
, and passing it toPDFPage.create_pages()
- I don't bother handling
LTFigure
s, since PDFMiner is currently incapable of cleanly handling text inside them anyway.
LAParams
lets you set some parameters that control how individual characters in the PDF get magically grouped into lines and textboxes by PDFMiner. If you're surprised that such grouping is a thing that needs to happen at all, it's justified in the pdf2txt docs:
In an actual PDF file, text portions might be split into several chunks in the middle of its running, depending on the authoring software. Therefore, text extraction needs to splice text chunks.
LAParams
's parameters are, like most of PDFMiner, undocumented, but you can see them in the source code or by calling help(LAParams)
at your Python shell. The meaning of some of the parameters is given at https://pdfminer-docs.readthedocs.io/pdfminer_index.html#pdf2txt-py since they can also be passed as arguments to pdf2text
at the command line.
The layout
object above is an LTPage
, which is an iterable of "layout objects". Each of these layout objects can be one of the following types...
LTTextBox
LTFigure
LTImage
LTLine
LTRect
... or their subclasses. (In particular, your textboxes will probably all be LTTextBoxHorizontal
s.)
More detail of the structure of an LTPage
is shown by this image from the docs:
Each of the types above has a .bbox
property that holds a (x0, y0, x1, y1) tuple containing the coordinates of the left, bottom, right, and top of the object respectively. The y-coordinates are given as the distance from the bottom of the page. If it's more convenient for you to work with the y-axis going from top to bottom instead, you can subtract them from the height of the page's .mediabox
:
x0, y0_orig, x1, y1_orig = some_lobj.bboxy0 = page.mediabox[3] - y1_origy1 = page.mediabox[3] - y0_orig
In addition to a bbox
, LTTextBox
es also have a .get_text()
method, shown above, that returns their text content as a string. Note that each LTTextBox
is a collection of LTChar
s (characters explicitly drawn by the PDF, with a bbox
) and LTAnno
s (extra spaces that PDFMiner adds to the string representation of the text box's content based upon the characters being drawn a long way apart; these have no bbox
).
The code example at the beginning of this answer combined these two properties to show the coordinates of each block of text.
Finally, it's worth noting that, unlike the other Stack Overflow answers cited above, I don't bother recursing into LTFigure
s. Although LTFigure
s can contain text, PDFMiner doesn't seem capable of grouping that text into LTTextBox
es (you can try yourself on the example PDF from https://stackoverflow.com/a/27104504/1709587) and instead produces an LTFigure
that directly contains LTChar
objects. You could, in principle, figure out how to piece these together into a string, but PDFMiner (as of version 20181108) can't do it for you.
Hopefully, though, the PDFs you need to parse don't use Form XObjects with text in them, and so this caveat won't apply to you.
Full disclosure, I am one of the maintainers of pdfminer.six. It is a community-maintained version of pdfminer for python 3.
Nowadays, pdfminer.six has multiple API's to extract text and information from a PDF. For this use case I would advice to use the high-level function extract_pages()
. This allows you to inspect all of the elements on a page, ordered in a meaningful hierarchy created by the layout algorithm.
The following example is a pythonic way of showing all the elements in the hierachy. It uses the simple1.pdf from the samples directory of pdfminer.six.
import osfrom typing import Iterablefrom pdfminer.high_level import extract_pagesfrom pdfminer.layout import LTItemdef show_ltitem_hierarchy(o: LTItem, depth=0): """Show location and text of LTItem and all its descendants""" if depth == 0: print('element x1 y1 x2 y2 text') print('------------------------------ --- --- --- ---- -----') print( f'{get_indented_name(o, depth):<30.30s} ' f'{get_optional_bbox(o)} ' f'{get_optional_text(o)}' ) if isinstance(o, Iterable): for i in o: show_ltitem_hierarchy(i, depth=depth + 1)def get_optional_text(o: LTItem) -> str: """Text of LTItem if available, otherwise empty string""" if hasattr(o, 'get_text'): return o.get_text().strip() return ''def get_indented_name(o: LTItem, depth: int) -> str: """Indented name of LTItem""" return ' ' * depth + o.__class__.__name__def get_optional_bbox(o: LTItem) -> str: """Bounding box of LTItem if available, otherwise empty string""" if hasattr(o, 'bbox'): return ''.join(f'{i:<4.0f}' for i in o.bbox) return ''file_path = '~/Downloads/simple1.pdf'show_ltitem_hierarchy(extract_pages(os.path.expanduser(file_path)))
The output shows the different elements in the hierarchy. The bounding box for each. And the text that this element contains.
element x1 y1 x2 y2 text------------------------------ --- --- --- ---- -----generator LTPage 0 0 612 792 LTTextBoxHorizontal 100 695 161 719 Hello LTTextLineHorizontal 100 695 161 719 Hello LTChar 100 695 117 719 H LTChar 117 695 131 719 e LTChar 131 695 136 719 l LTChar 136 695 141 719 l LTChar 141 695 155 719 o LTChar 155 695 161 719 LTAnno LTTextBoxHorizontal 261 695 324 719 World LTTextLineHorizontal 261 695 324 719 World LTChar 261 695 284 719 W LTChar 284 695 297 719 o LTChar 297 695 305 719 r LTChar 305 695 311 719 l LTChar 311 695 324 719 d LTAnno LTTextBoxHorizontal 100 595 161 619 Hello LTTextLineHorizontal 100 595 161 619 Hello LTChar 100 595 117 619 H LTChar 117 595 131 619 e LTChar 131 595 136 619 l LTChar 136 595 141 619 l LTChar 141 595 155 619 o LTChar 155 595 161 619 LTAnno LTTextBoxHorizontal 261 595 324 619 World LTTextLineHorizontal 261 595 324 619 World LTChar 261 595 284 619 W LTChar 284 595 297 619 o LTChar 297 595 305 619 r LTChar 305 595 311 619 l LTChar 311 595 324 619 d LTAnno LTTextBoxHorizontal 100 495 211 519 H e l l o LTTextLineHorizontal 100 495 211 519 H e l l o LTChar 100 495 117 519 H LTAnno LTChar 127 495 141 519 e LTAnno LTChar 151 495 156 519 l LTAnno LTChar 166 495 171 519 l LTAnno LTChar 181 495 195 519 o LTAnno LTChar 205 495 211 519 LTAnno LTTextBoxHorizontal 321 495 424 519 W o r l d LTTextLineHorizontal 321 495 424 519 W o r l d LTChar 321 495 344 519 W LTAnno LTChar 354 495 367 519 o LTAnno LTChar 377 495 385 519 r LTAnno LTChar 395 495 401 519 l LTAnno LTChar 411 495 424 519 d LTAnno LTTextBoxHorizontal 100 395 211 419 H e l l o LTTextLineHorizontal 100 395 211 419 H e l l o LTChar 100 395 117 419 H LTAnno LTChar 127 395 141 419 e LTAnno LTChar 151 395 156 419 l LTAnno LTChar 166 395 171 419 l LTAnno LTChar 181 395 195 419 o LTAnno LTChar 205 395 211 419 LTAnno LTTextBoxHorizontal 321 395 424 419 W o r l d LTTextLineHorizontal 321 395 424 419 W o r l d LTChar 321 395 344 419 W LTAnno LTChar 354 395 367 419 o LTAnno LTChar 377 395 385 419 r LTAnno LTChar 395 395 401 419 l LTAnno LTChar 410 395 424 419 d LTAnno