In reading journal articles for school, I often come across pdfs where I cannot select text, which makes taking notes very inconvenient. The funny thing is, the pdf does not appear to be scanned, and the security permissions allow for copying, but the text does not enable me to do so. How can I convert this pdf into a pdf where I can select the text, preferably without having to convert each page individually, as there are typically 20 pages per pdf.
I've tried some online converters, but I can't seem to find one that can 'digitize' the text while maintaining the file in a pdf format.
Any suggestions? Any background information to explain this helps as well.
Thanks much.
Try to "print" the original pdf file into a new pdf archive by using "PDF Creator" or a similar application. In the new file you should be able to select the text.
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I have access to a scanner at my library which can create "searchable PDFs." These are PDFs that show the exact image of a scanned document, but there is a kind of hidden text in the PDF that can be selected when you try to select a portion of the image that contains text. In this way you can copy and paste text or search for text in the scanned document. This is VERY useful. It's an awesome improvement over raw scanned images. I also have several apps on my mac that can create this kind of searchable PDF from a scanned document or a raw image.
Now it's obvious from any who has ever used OCR that the process of converting images to text is not 100% accurate, so the text that you search or copy will not be correct in some places.
So I search for quite some time to find an application that would load a searchable PDF and allow me to repair the hidden searchable text without reformatting or modifying the original scanned image.
Does anyone know of a tool (or library API) that would allow this?
It's worth saying here that I tried the latest version of Adobe Acrobat DC for Mac, and it doesn't seem to even allow me to view the hidden searchable text, much less edit it. It does allow me to replace scanned image with the results of it's own OCR process so that I could edit and save the document. But this would produce horrible results for any of the scanned documents that I am using. It seems designed for editing a "native PDF" not editing a scanned document.
I have also tried ABBYY FineReader with no luck.
i'm using ABBYY FineReader 12 Professional. (not open source)
Just open a scanned image or scanned pdf and press Verify Text(or Ctrl + F7), than you go over all the spelling errors or low-confidence charachters and fix them.
The program is very good, it shows you the exact place in image/pdf to correct and the OCR guessing side by side for convenience. It iterates all of them.
[By the way, I'm using the shortcuts to speed up things:
Alt+Enter to add the unrecognized word to dictionary.
Ctrl+Delete to skip word or confirm in case you fixed it.]
Than save the document as a pdf file Menu:File>Save Document As> PDF File, and you can search it on every pdf reader. The saved file look the same as the scanned one, but 'behind' it there text.
It's weird you tried ABBYY with no luck... it's working great for me. maybe you tried not the Professional version.
Hope it helps you.
It is not creating a searchable pdf from images the poster is after, he wants to start with an already searchable pdf and modify its text (e.g. because intially a searchable pdf was made but later an overlooked error in recognition was found and needs correction). I see no way and no tool that assists in doing this.
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 a few hundred PDF files from which I need to extract sections of text. For many, pdftotext works fine, but for others, it misses large sections of text. If I open the PDF in Acrobat and select that text by hand and copy/paste into emacs and then view the file without an encoding, I get stuff like this:
Husband \364\200\200\272\364\200\201\213\364 etc.
How can I extract the text correctly?
I should mention that I've tried saving as text from Acrobat; also tried applying Acrobat's Document=>OCR feature before copying.
Why not convert the PDF to doc or txt first? See the guide:
http://www.aolor.com/pdf-converter/user-guide.html
I have a piece of software called PDF2XL which is normally great for extracting tables of data from PDF files. I've used it with hundreds of files before.
This one file though, gives me gibberish output that I can't even copy and paste into this textarea correctly. All sorts of unicode weirdness.
If I copy and paste as per normal into excel/notepad I get the same issue.
I assume it's something to do with a messed up character encoding header in the PDF file? How can I change this? I'm on Windows and have no software that can edit PDFs, so if I need to edit/re-save it, please recommend a free piece of SW to do it.
Thanks!
There are an increasing number of PDF files the used subsetted fonts which is basically a custom encoding. Normally the font descriptor in the PDF should have a ToUnicode table to allow the text extraction to decode the font encoding and return the correct text.
Some PDF producers are doing this on purpose to prevent easy PDF text extraction for things such as financial reports. If there is only one font then you could manually decode the font but in my experience I have seen PDF's with multiple random encodings which makes it nearly impossible to decode automatically.
One way to test for these types of PDF's is to open the file in Acrobat, select some text, copy it and then paste it into Notepad. If the text is garbled then the PDF is using a subsetted font and there is not much more you can do. If Acrobat can't extract the text correctly then nothing else can. It may as well be a page of hieroglyphs.
I'm working on a project that involves the Fannie Mae/Freddie Mac Uniform Appraisal Dataset. The specification requires that the embedded appraisal PDF file be first-generation.
I understand conceptually what a first-generation PDF file is (printing of a document directly to PDF, rather than a scanned copy or printed and scanned copy). However, I've done some research and haven't found anything that specifies the properties of a first-generation PDF that could be verified programmatically.
I found a product that allows one to check if a PDF contains text, images, or both: Apose.Pdf.Kit for .NET, but I'm looking for a way to program this myself, for budgetary and other reasons. Also, I'm not sure that determining that the file contains text will be sufficient to verify that it's first-generation.
Given that this is an industry requirement of a very large industry, I feel like someone must have already tackled this issue, but I'm having a hard time finding anything.
Thanks in advance for any help.
There is no way to know for certain if a PDF is "first generation". Technically, a scanned PDF is just a PDF that contains images and perhaps OCR'ed text on top of that. A "first generation" PDF could easily have the same characteristics, so you have to use some heuristics.
For example, a PDF that contains only images and invisible text (from OCR) is likely to be scanned, a PDF that has visible text or vector graphics is probably "first generation" (OCR for scanned PDFs works by overlaying invisible text on top of the original image, so that text selection works, but the original document's fidelity is preserved).
Open pdf, ctrl "f" type in Appraisal. If you have a hit for the word, you have a first generation apprsl. Rather, the dataset exist.