We have used the above algorithm suggested in the link to read the highlighted text from PDF files. It works fine with single line highlights.
However, text read from multiple line highlights is incorrect. Final text read from highlight is completely jumbled with neighboring lines text.
Help us in resolving the above issue. - Thanks
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I have searched for an answer to this question but perhaps I am searching with the incorrect terminology as I have found nothing so far. Any help would be great!
I would like to extract the positions of text fields, check boxes, radio buttons, list boxes, etc. from an Adobe PDF file. Is there a way to do this? Is there a way to do this with Python?
Thanks for your help!
Does this post help? It runs through extracting text from a pdf and has a line of code commented out which will show the coordinates of text. Finding and extracting specific text from URL PDF files, without downloading or writing (solution)
I have an application, that extracts headings out of pdf files. The documents, that the application is supposed to work with, all have more or less coherent structure and formatting, in fact, telling if a text chunk is bold or not, is very important. Recently I came across a bunch of files, where some chunks visually appear bold, but do not have "bold" piece in string representation of font. The following SO thread how can i get text formatting with iTextSharp helped me to understand, that there is one more way of making text appear bold. However in my case calling GetTextRenderMode() does not help either, as it returns 0 as if it were normal text. So are there any other ways of making text appear bold, and is it possible to detect it using iTextSharp ?
You are making the assumption that the font inside your PDF file knows if it's bold or not. Let's take a look inside and check if your assumption is correct.
This is what the subset JOJJAH of the font TT116t00 looks like when you look at the internals of the PDF file you have shared:
We see that the font is of subtye /TrueType, we see that the /ItalicAngle is 0, and... we see that the 3rd bit of the /Flags is set. Let's check the PDF reference to find out what this tells us:
I quote:
The font contains glyphs outside the Adobe standard Latin character set.
The glyphs look bold, because the glyphs are drawn in a way that they appear bold. You see the font as bold because you are human. However, when a machine looks at the font, it doesn't have a clue that the font is bold. A machine just follows the instructions stored in the /FontFile2 stream.
In short: iTextSharp doesn't have any indications that the font is bold.
I have a visual basic program that extracts text from a PDF and imports the text into excel. It relies on reading the text like a human, reading left to right across the page. However, there are instances on this particular PDF where if I go to select the text with my mouse, I click and drag straight across but Adobe starts to select/highlight words on the above and below lines before continuing to highlight across the page. This gives me data that I do not want/need. The page has renderable text and is not from a scanned document.
Is there a way to "reset" the way Adobe interprets the text on the PDF? Since the information on the left is far from the information on the right, it treats them almost like separate columns.
I've tried saving the PDF in different formats such as a txt or postscript and distilling to another PDF but they all seem to result in the same outcome. This is weird to me because I have other similar PDFs where this isn't an issue.
Any help or thoughts would be greatly appreciated, thanks.
As PDF (in its basic form) essentially means placing strings on a canvas, the concept of "sentence" or "reading order" is not built in.
In order to extract text, you would have to read out the bounding box of the piece of text, and then use some logic and heuristics to assemble your text based on the coordinates of the bounding box.
Things can be easier if the PDF is a structured PDF, where the text contents is embedded as text in the document. This is also the prime requirement for an accessible document. So, if your document is accessible, you can rely on the structure for the correct reading order.
I have an application, that extracts headings out of pdf files. The documents, that the application is supposed to work with, all have more or less coherent structure and formatting, in fact, telling if a text chunk is bold or not, is very important. Recently I came across a bunch of files, where some chunks visually appear bold, but do not have "bold" piece in string representation of font. The following SO thread how can i get text formatting with iTextSharp helped me to understand, that there is one more way of making text appear bold. However in my case calling GetTextRenderMode() does not help either, as it returns 0 as if it were normal text. So are there any other ways of making text appear bold, and is it possible to detect it using iTextSharp ?
You are making the assumption that the font inside your PDF file knows if it's bold or not. Let's take a look inside and check if your assumption is correct.
This is what the subset JOJJAH of the font TT116t00 looks like when you look at the internals of the PDF file you have shared:
We see that the font is of subtye /TrueType, we see that the /ItalicAngle is 0, and... we see that the 3rd bit of the /Flags is set. Let's check the PDF reference to find out what this tells us:
I quote:
The font contains glyphs outside the Adobe standard Latin character set.
The glyphs look bold, because the glyphs are drawn in a way that they appear bold. You see the font as bold because you are human. However, when a machine looks at the font, it doesn't have a clue that the font is bold. A machine just follows the instructions stored in the /FontFile2 stream.
In short: iTextSharp doesn't have any indications that the font is bold.
I have just recently been experimenting with parsing the text data from a PDF document using iTextSharp in a VB2010 app. the document doesn't contain any images or other fancy elements, just text. Ive read some articles and used some code snippets and it looks promising. However, what Ive been trying to do is just parse out the body of each page, minus a header or footer. I haven't found any guidance for that particular function.
Currently using the snippet found here Reading PDF content with itextsharp dll in VB.NET or C# but it parses all text in a page. There's got to be a way to just get the body. Or at least I hope so.
PDFs generally do not contain information about logical structure of contained text.
So there are no headers, footers, body, paragraphs and anything like this in a PDF. There is only bunch of operations like "draw this glyph here", "move to this position and draw that group of glyphs there". I wrote glyph and not character because PDFs are not required to contain readable text. Only visual appearance required to be specified.
One exception is Tagged PDF but most of PDFs in the wild are not tagged.
Given all of the above you are probably left with following approach:
Extract all text from each page
Analyze text and find similar parts at the beginning / end of each page
Remove similar parts
This is a heuristic-based detection, so it probably won't always give excellent results.