#Pdf text extractor python pdf#
#Pdf text extractor python software#

Will also never be able to extract text from images.Īnd finally there are issues that PyPDF2 will deal with.

#Pdf text extractor python software#

Is no OCR software it will not be able to detect those failures. Software (OCR) is pretty good today, it still fails once in a while. That typically happens when a document was scanned.

#Pdf text extractor python pdf#

Then thereĪre PDF files that contain an image and a text layer in the background. You notice that when you cannot copy the text. Images: Sometimes PDFs do not contain the text as it’s displayed, but In the worstĬase, ever single letter could be absolutely positioned. Tables: Typically, tables are just absolutely positioned text. The way PDF stores information just makes it hard to achieve that:

Then there are issues where most people would agree on the correct output, but Linearization: Assume you have a floating figure in between a paragraph.ĭo you first finish the paragraph or do you put the figure text in between? Hyperlinks and Metadata: Should it be extracted at all? Where should it Horizontal whitespace? When would you extract tabs and when spaces?įootnotes: When the text of multiple pages is extracted, where should footnotes be shown? Vertical whitespace? How many spaces should be extracted if there is 3cm of Whitespace characters: How many new lines should be extracted for 3cm of Mathematical Formulas: Should they be extracted? Formulas have indices, SVG images: Should the text parts be extracted? The Unicode symbol ‘ﬀ’ or as two ASCII symbols ‘ff’? Is a single symbol ﬀ for two lowercase letters ‘f’. as an HTML table? How would you deal with mergedĬaptions: Should image and table captions be included? Text? Should the borders be shown in some Markdown-like way or should the Tables: Should the text extraction skip tables? Should it extract just the Outlines: Should outlines be extracted at all?įormatting: If text is bold or italic, should it be included in the Headers and Footers: Similar to page numbers - should they be extracted? Page numbers: Should they be included in the extract? Where the original PDF had them or should it rather be one block of text? Paragraphs: Should the text of a paragraph have line breaks at the same places In several cases there is noĬlear answer what the expected result should look like: Why Text Extraction is hard Įxtracting text from a PDF can be pretty tricky. Unfortunately in complicated PDF documents the coordinates given to the visitor-functions may be wrong. The SVG generated here is bottom-up because the coordinate systems of PDF and SVG differ. extract_text ( visitor_operand_before = visitor_svg_rect, visitor_text = visitor_svg_text ) dwg. text ( text, insert = ( x, y ), fill = 'blue' )) page. rect (( x, y ), ( w, h ), stroke = 'red', fill_opacity = 0.05 )) def visitor_svg_text ( text, cm, tm, fontDict, fontSize ): ( x, y ) = ( tm, tm ) dwg. Drawing ( 'GeoBase_test.svg', profile = 'tiny' ) def visitor_svg_rect ( op, args, cm, tm ): if op = b 're' : ( x, y, w, h ) = ( args. The following example reads the text of page 4 of this PDF document, but ignores header (y 50).įrom PyPDF2 import PdfReader import svgwrite reader = PdfReader ( 'GeoBase_NHNC1_Data_Model_UML_EN.pdf' ) page = reader. Operand, operand-arguments, current transformation matrix and text matrix.

The function provided in argument visitor_operand_before has four arguments: contain key “/BaseFont” with value “/Arial,Bold”.Ĭaveat: In complicated documents the calculated positions might be wrong.

The font-dictionary may be None in case of unknown fonts. In most cases the x and y coordinates of the current positionĪre in index 4 and 5 of the current transformation matrix. The function provided in argument visitor_text of function extract_text has five arguments:Ĭurrent transformation matrix, text matrix, font-dictionary and font-size. The visitor-functions you provide will get called for each operator or for each text fragment. You can use visitor-functions to control which part of a page you want to process and extract. extract_text ( 0 )) # extract text oriented up and turned left print ( page. # extract only text oriented up print ( page.

Example 2: Extract rectangles and texts into a SVG-file.