Extract text from pdf python

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    All of you must be familiar with what PDFs are. In fact, they are one of the most important and widely used digital media. PDF stands for Portable Document Format. It uses .pdf extension. It is used to present and exchange documents reliably, independent of software, hardware, or operating system.

    Extracting Text from PDF File

    Python package PyPDF can be used to achieve what we want (text extraction), although it can do more than what we need. This package can also be used to generate, decrypting and merging PDF files.

    Note: For more information, refer to Working with PDF files in Python

    Installation

    To install this package type the below command in the terminal.

    pip install PyPDF2

    Example:

    Input PDF:

    Extract text from pdf python

    import PyPDF2 

    pdfFileObj = open('example.pdf', 'rb'

    pdfReader = PyPDF2.PdfFileReader(pdfFileObj) 

    print(pdfReader.numPages) 

    pageObj = pdfReader.getPage(0

    print(pageObj.extractText()) 

    pdfFileObj.close() 

    Output:

    Extract text from pdf python

    Let us try to understand the above code in chunks:

    • pdfFileObj = open('example.pdf', 'rb')

      We opened the example.pdf in binary mode. and saved the file object as pdfFileObj.

    • pdfReader = PyPDF2.PdfFileReader(pdfFileObj)

      Here, we create an object of PdfFileReader class of PyPDF2 module and  pass the pdf file object & get a pdf reader object.

    • print(pdfReader.numPages)

      numPages property gives the number of pages in the pdf file. For example, in our case, it is 20 (see first line of output).

    • pageObj = pdfReader.getPage(0)

      Now, we create an object of PageObject class of PyPDF2 module. pdf reader object has function getPage() which takes page number (starting form index 0) as argument and returns the page object.

    • print(pageObj.extractText())

      Page object has function extractText() to extract text from the pdf page.

    • pdfFileObj.close()

      At last, we close the pdf file object.

    I am adding code to accomplish this: It is working fine for me:

    # This works in python 3
    # required python packages
    # tabula-py==1.0.0
    # PyPDF2==1.26.0
    # Pillow==4.0.0
    # pdfminer.six==20170720
    
    import os
    import shutil
    import warnings
    from io import StringIO
    
    import requests
    import tabula
    from PIL import Image
    from PyPDF2 import PdfFileWriter, PdfFileReader
    from pdfminer.converter import TextConverter
    from pdfminer.layout import LAParams
    from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter
    from pdfminer.pdfpage import PDFPage
    
    warnings.filterwarnings("ignore")
    
    
    def download_file(url):
        local_filename = url.split('/')[-1]
        local_filename = local_filename.replace("%20", "_")
        r = requests.get(url, stream=True)
        print(r)
        with open(local_filename, 'wb') as f:
            shutil.copyfileobj(r.raw, f)
    
        return local_filename
    
    
    class PDFExtractor():
        def __init__(self, url):
            self.url = url
    
        # Downloading File in local
        def break_pdf(self, filename, start_page=-1, end_page=-1):
            pdf_reader = PdfFileReader(open(filename, "rb"))
            # Reading each pdf one by one
            total_pages = pdf_reader.numPages
            if start_page == -1:
                start_page = 0
            elif start_page < 1 or start_page > total_pages:
                return "Start Page Selection Is Wrong"
            else:
                start_page = start_page - 1
    
            if end_page == -1:
                end_page = total_pages
            elif end_page < 1 or end_page > total_pages - 1:
                return "End Page Selection Is Wrong"
            else:
                end_page = end_page
    
            for i in range(start_page, end_page):
                output = PdfFileWriter()
                output.addPage(pdf_reader.getPage(i))
                with open(str(i + 1) + "_" + filename, "wb") as outputStream:
                    output.write(outputStream)
    
        def extract_text_algo_1(self, file):
            pdf_reader = PdfFileReader(open(file, 'rb'))
            # creating a page object
            pageObj = pdf_reader.getPage(0)
    
            # extracting extract_text from page
            text = pageObj.extractText()
            text = text.replace("\n", "").replace("\t", "")
            return text
    
        def extract_text_algo_2(self, file):
            pdfResourceManager = PDFResourceManager()
            retstr = StringIO()
            la_params = LAParams()
            device = TextConverter(pdfResourceManager, retstr, codec='utf-8', laparams=la_params)
            fp = open(file, 'rb')
            interpreter = PDFPageInterpreter(pdfResourceManager, device)
            password = ""
            max_pages = 0
            caching = True
            page_num = set()
    
            for page in PDFPage.get_pages(fp, page_num, maxpages=max_pages, password=password, caching=caching,
                                          check_extractable=True):
                interpreter.process_page(page)
    
            text = retstr.getvalue()
            text = text.replace("\t", "").replace("\n", "")
    
            fp.close()
            device.close()
            retstr.close()
            return text
    
        def extract_text(self, file):
            text1 = self.extract_text_algo_1(file)
            text2 = self.extract_text_algo_2(file)
    
            if len(text2) > len(str(text1)):
                return text2
            else:
                return text1
    
        def extarct_table(self, file):
    
            # Read pdf into DataFrame
            try:
                df = tabula.read_pdf(file, output_format="csv")
            except:
                print("Error Reading Table")
                return
    
            print("\nPrinting Table Content: \n", df)
            print("\nDone Printing Table Content\n")
    
        def tiff_header_for_CCITT(self, width, height, img_size, CCITT_group=4):
            tiff_header_struct = '<' + '2s' + 'h' + 'l' + 'h' + 'hhll' * 8 + 'h'
            return struct.pack(tiff_header_struct,
                               b'II',  # Byte order indication: Little indian
                               42,  # Version number (always 42)
                               8,  # Offset to first IFD
                               8,  # Number of tags in IFD
                               256, 4, 1, width,  # ImageWidth, LONG, 1, width
                               257, 4, 1, height,  # ImageLength, LONG, 1, lenght
                               258, 3, 1, 1,  # BitsPerSample, SHORT, 1, 1
                               259, 3, 1, CCITT_group,  # Compression, SHORT, 1, 4 = CCITT Group 4 fax encoding
                               262, 3, 1, 0,  # Threshholding, SHORT, 1, 0 = WhiteIsZero
                               273, 4, 1, struct.calcsize(tiff_header_struct),  # StripOffsets, LONG, 1, len of header
                               278, 4, 1, height,  # RowsPerStrip, LONG, 1, lenght
                               279, 4, 1, img_size,  # StripByteCounts, LONG, 1, size of extract_image
                               0  # last IFD
                               )
    
        def extract_image(self, filename):
            number = 1
            pdf_reader = PdfFileReader(open(filename, 'rb'))
    
            for i in range(0, pdf_reader.numPages):
    
                page = pdf_reader.getPage(i)
    
                try:
                    xObject = page['/Resources']['/XObject'].getObject()
                except:
                    print("No XObject Found")
                    return
    
                for obj in xObject:
    
                    try:
    
                        if xObject[obj]['/Subtype'] == '/Image':
                            size = (xObject[obj]['/Width'], xObject[obj]['/Height'])
                            data = xObject[obj]._data
                            if xObject[obj]['/ColorSpace'] == '/DeviceRGB':
                                mode = "RGB"
                            else:
                                mode = "P"
    
                            image_name = filename.split(".")[0] + str(number)
    
                            print(xObject[obj]['/Filter'])
    
                            if xObject[obj]['/Filter'] == '/FlateDecode':
                                data = xObject[obj].getData()
                                img = Image.frombytes(mode, size, data)
                                img.save(image_name + "_Flate.png")
                                # save_to_s3(imagename + "_Flate.png")
                                print("Image_Saved")
    
                                number += 1
                            elif xObject[obj]['/Filter'] == '/DCTDecode':
                                img = open(image_name + "_DCT.jpg", "wb")
                                img.write(data)
                                # save_to_s3(imagename + "_DCT.jpg")
                                img.close()
                                number += 1
                            elif xObject[obj]['/Filter'] == '/JPXDecode':
                                img = open(image_name + "_JPX.jp2", "wb")
                                img.write(data)
                                # save_to_s3(imagename + "_JPX.jp2")
                                img.close()
                                number += 1
                            elif xObject[obj]['/Filter'] == '/CCITTFaxDecode':
                                if xObject[obj]['/DecodeParms']['/K'] == -1:
                                    CCITT_group = 4
                                else:
                                    CCITT_group = 3
                                width = xObject[obj]['/Width']
                                height = xObject[obj]['/Height']
                                data = xObject[obj]._data  # sorry, getData() does not work for CCITTFaxDecode
                                img_size = len(data)
                                tiff_header = self.tiff_header_for_CCITT(width, height, img_size, CCITT_group)
                                img_name = image_name + '_CCITT.tiff'
                                with open(img_name, 'wb') as img_file:
                                    img_file.write(tiff_header + data)
    
                                # save_to_s3(img_name)
                                number += 1
                    except:
                        continue
    
            return number
    
        def read_pages(self, start_page=-1, end_page=-1):
    
            # Downloading file locally
            downloaded_file = download_file(self.url)
            print(downloaded_file)
    
            # breaking PDF into number of pages in diff pdf files
            self.break_pdf(downloaded_file, start_page, end_page)
    
            # creating a pdf reader object
            pdf_reader = PdfFileReader(open(downloaded_file, 'rb'))
    
            # Reading each pdf one by one
            total_pages = pdf_reader.numPages
    
            if start_page == -1:
                start_page = 0
            elif start_page < 1 or start_page > total_pages:
                return "Start Page Selection Is Wrong"
            else:
                start_page = start_page - 1
    
            if end_page == -1:
                end_page = total_pages
            elif end_page < 1 or end_page > total_pages - 1:
                return "End Page Selection Is Wrong"
            else:
                end_page = end_page
    
            for i in range(start_page, end_page):
                # creating a page based filename
                file = str(i + 1) + "_" + downloaded_file
    
                print("\nStarting to Read Page: ", i + 1, "\n -----------===-------------")
    
                file_text = self.extract_text(file)
                print(file_text)
                self.extract_image(file)
    
                self.extarct_table(file)
                os.remove(file)
                print("Stopped Reading Page: ", i + 1, "\n -----------===-------------")
    
            os.remove(downloaded_file)
    
    
    # I have tested on these 3 pdf files
    # url = "http://s3.amazonaws.com/NLP_Project/Original_Documents/Healthcare-January-2017.pdf"
    url = "http://s3.amazonaws.com/NLP_Project/Original_Documents/Sample_Test.pdf"
    # url = "http://s3.amazonaws.com/NLP_Project/Original_Documents/Sazerac_FS_2017_06_30%20Annual.pdf"
    # creating the instance of class
    pdf_extractor = PDFExtractor(url)
    
    # Getting desired data out
    pdf_extractor.read_pages(15, 23)
    

    How do I extract text from a PDF in Python?

    pdf reader object has function getPage() which takes page number (starting form index 0) as argument and returns the page object. Page object has function extractText() to extract text from the pdf page. At last, we close the pdf file object.

    How do I extract data from a PDF in Python?

    There are a couple of Python libraries using which you can extract data from PDFs. For example, you can use the PyPDF2 library for extracting text from PDFs where text is in a sequential or formatted manner i.e. in lines or forms. You can also extract tables in PDFs through the Camelot library.

    How do I extract text from a PDF?

    How to Extract Text from a PDF.
    Open the PDF Document you wish to convert..
    Go to the Convert Tab > Convert To > Text on the toolbar..
    Choose a file name and location to save the .txt document that will contain the extracted text..
    Click Save to extract the text and to the file selected..

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