Our syllabus says we have to read a scanned PDF for next week, but I cannot select or highlight any of the words on my laptop. Is it basically just an image saved as a document?
Yep, exactly. It’s basically photos of pages saved as a PDF, so there’s no actual text for your cursor to grab. I deal with this all the time with old scanned drawings at work. If you need to search or copy from it, you’d have to run OCR on it, which adds a text layer over the image.
Yes, exactly that. I had the same issue with our old clinic records; it is essentially just a photograph of a page, so your laptop cannot recognise actual letters. To highlight it, I usually run the file through OCR (text recognition) on PDFcap, which makes all the words selectable for me.
You hit the nail on the head; it is literally just a digital photograph of a page. I learned this the hard way when trying to extract old bread recipes to format into an EPUB. Try opening the file in Microsoft Word, as newer versions can sometimes recognise the text. Avoid wasting time trying to highlight it directly because your computer just sees a flat picture.
Yes, that is pretty much exactly it. A scanned PDF is just a photo of each page stuffed into a PDF file, so there is no actual text layer for your computer to recognize, which is why you cannot select or highlight anything. If you need to search or copy from it, you would want it run through OCR first, but for just reading it should work fine as is.
@SneakySteel Right, my old laptop chokes on those scans too. Word actually pulls the text in sometimes, so worth a try, not sure if it’s the same on Mac.
@Emily.7 Word can sometimes pull text from a scan, though the results may need checking, especially with old or blurry pages. For citations, I’d compare the extracted wording and page numbers against the scanned image before relying on it.
Yes, usually it is page images made from a physical book, so the words are not actual text and cannot be selected. Some scans have OCR added, which creates a searchable text layer, but it can be imperfect. For reading, I usually use a PDF viewer’s annotation tools to draw highlights, or run OCR first if I need to quote or search it.
Yes, that’s basically it. A scanned PDF usually contains page images, sometimes with invisible text added by OCR. If you can’t select the words, your copy may not have an OCR text layer, though some viewers have their own “recognize text” option worth trying. Also check whether your professor’s copy includes a searchable version, since that often makes a big difference.