Best way to scrape text from a PDF or User Interface (UI)?

So for a long time I have needed to extract information from various standard government forms and User Interface elements, and I have been using really dumb brute force mechanisms. I was wondering what others do to extract such info?

There seems to be maybe 4 mechanisms (Brute force clicks, image search, some sophisticated UI inquiry, perhaps an OCR technique) that I’m aware of, but each has issues and I’m wondering what others use/do to get/pull/scrape out information they need to operate on from a document or UI element.

Brute force
For example, have KM make a PDF window a set size in and then just double click some exact X/Y location in the document and copy the selected text. This used to work well enough in most cases in the past. I would also do this to automate parts of interacting with the UI, just make KM click at an XY location to click a button. It mostly works. Of course a big problem with brute force is that Apple changes the UI font/spacing and the macro clicks will break. Or the form I’m working with will be scanned and the positioning of a form element will be off just enough that a click may be misaligned and get the wrong data. Also, now that Apple OCRs text you click on in a PDF it copies the invisible already OCRd text from the PDF and the apple OCR from the click on the bitmap and you end up copying double values.

Image search
I’ve tried this and it works ok some\times but is generally unreliable and weirdly variable. For example, I may grab a screen image of an “OK” or “Save” button in a UI to click on, and it will rightly click on it 9 out of 10 times but seems to fail. A lot of times I think the failure was if the screen went into dark mode I guess the image match fails regardless of how much slack you give on the tolerance slider. Fine I turn off dark mode, but it still fail, I suspect because some windows have subtle transparency and depending on where the window will pop up with some variable background image, I guess the image search can’t see.

Worse still, if I try to look for some text field in a PDF document like “Mailing Date” to then click the text to the right of it and scrape out the mailing date, it fails 50% of the time and doesn’t see “Mailing date” I’m guessing because of subtle differences in how that text was rostered from form to form. But the visual search also fails hard for text in the user interface, like the soft grey text in a compose window for “Subject” or “ CC:” despite such rendering supposedly being identical in every window (perhaps again because those windows have soft transparency so the bitmap it finds on becomes just too different).

Sophisticated UI inquiry
I believe with apple script there are some cool ways you can query for different values of a UI. So there may be someway to say what is the text field in this window, or the text value of this button in a panel. KM has at least some ways of getting at some UI elements, like the name of a window. But I’m not familiar is there some kind of command that says “find a UI button with text containing ‘save’ and engage it” or “find a right click menu item that contains text “export and engage it” or something like that? My guess is it’s not possible without some AppleScript hacking but perhaps I’m missing something simple.

OCR technique
All I really want to do with scraping some info from a PDF is look for a field prompt and copy out some characters to the right or below that field. So for example I might have “Re:”-line that will have some subject to the right of that line, and a “Mail Date:” that may have a mailing date just to the right of that label, and a “Return Address:” just below that label. I know that KM can OCR a document but I didn’t see any selection scraping tools from that OCR’ing. For example, is there something like “OCR for ‘Mail Date: and select next 10 characters’ type of command?

TLDR: Anyway, for now I use a mishmash of brute force and image searching but I get the feeling I’m missing much better ways to target those PDFs and UI elements and copy out those values and or engage the UI elements … and I’m hoping others here have some great silver bullet reliable ways to extract/scrape such values! Thanks so much for any pointers or a sanity check that in fact that’s about all that can be done with KM for scraping out data from the UI and PDFs.

These are two different threads on using the same method (the shell and xpdf toolkit).

I've used this method regularly for nearly a decade, although I'm still using Mojave and can't guarantee they'll work on later versions of macOS. I think so (they're 64-bit), but I haven't personally tested.

Those ways will work though take a bit of effort.

One very easy way is to OCR through Devonthink and then use its scripting capability to reveal the text content of the document. Very straightforward.

If you are looking for something much more powerful there are a number of ways to do PDF parsing in Python; it is ideally suited for the task and worth the effort to learn it.

Can these methods in Python preserve PDF document's layout?

xpdf tools can, and that's why I've used it for so long. Layout preservation typically makes reading and parsing the text much easier.

Thank you all so much. I’m hoping to find a technique that is fully contained within KM. I just want it to be easily portable from machine to machine. We share our macros across a number of machines and people, and it will be nice if the features we use are just fully within KM’s wheelhouse.

So it looks like brute force and image search ar basically the only ways, currently, to extract information from PDFs and UI screen elements.

While a little disappointing it does make me feel better that I was not missing something very obvious. Thank you so much.

This seems like maybe a great area to ask for a feature request for newer versions of KM. Maybe they would do some dedicated commands for both PDF and UI element extraction in a future release.

Do you have a link to a gov't webpage or form that you are working on?

If you are on recent OSs, give the "Get Text from PDF" Shortcut action a try. You could then ship both Shortcut and KM macro and use KM's "Execute Shortcut" action to get the text into your workflow.

Extracting text that makes sense from a format aimed more at cross-system display (originally print) fidelity than data exchange is non-trivial -- especially if the text isn't really text! But there are plenty of tools you can leverage with KM, from free (poppler via Homebrew) to OCR via DevonThink (and plenty of price points in-between), to build a decent workflow.

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In my opinion you're much better off taking the trouble to learn how to use xpdf tools.

macOS does provide the means to extract text from PDFs, but it's not pretty. Try this macro on the selected PDF file in the Finder.

Download: Extract Text From PDF File Selected in the Finder v1.00.kmmacros (7.8 KB)


Keyboard Maestro Export

  • Macros are always disabled when imported into the Keyboard Maestro Editor.
    • The user must ensure the macro is enabled.
    • The user must also ensure the macro's parent macro-group is enabled.

System Information
  • macOS 10.14.6
  • Keyboard Maestro v10.2

It may or may not be good enough for your needs.


@ccstone That script is very helpful - thank you.

Where is the documentation on the getTextFromPDF scripting command? I cannot find that in the script directory and would like to learn more.

There is no such thing. That's an AppleScriptObjC handler name written by a person.

If you want to know more about AppleScript then hang out in:

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