PDFs are generally an actual document, separate from the site they're on. > I mean it's not like we expect a PNG viewer or HTML5 video viewer to be a separate application in a browser. There's lots of libraries that try to do this for you, but there are lots because none get it right 100% of the time. There's also this whole thing with clipping, where some text can be hidden behind other objects (or off page) so you have to try to deal with that. If you want to 'read' the text, you have to work out the orientation (which can change throughout the page - think of table header alignment), and use some kind of heuristic to guess the word spacing based on the font and character spacing.

Instead of strings of text you have character glyphs positioned at a particular location. PDF isn't a 'document' format in that sense - it's a page description language. Most 'document' formats have the concept of words or strings: a set of characters separated by whitespace. Unlike HTML or formats like MS Word (XML or old binary format) getting 'text' isn't really possible. I think one of the biggest pain points that developers hit that hasn't been mentioned here is content extraction.Ī lot of the time developers want access to the text inside PDFs. We don't need non-greedy regex rules to do a less than comparison. I thought linking to a python script that shows the order comparison of a tuple (0,N) as less than the tuple (0,N+1) would clearly demonstrate this, but it appears to have failed to communicate that to you. Is it a valid pdf? no no no no no (no) no yes yes yes (yes) yes Therefore (0,infinity) can never be the first valid pdf, even though it may be a valid pdf. So if there is any valid pdf in pi that can be identified by the range tuple (0,N), then the first valid pdf must occur before N -> infinity. Where I'm from 'first' and 'less' are related (the first element in a unique sorted list is defined to be less than all other elements). Note the word 'next', implying that (0,10) sorts before (0,11) you even say it yourself '11 is less than infinity'. Or any after it up to and including (0,infinity).

Why is this so hard? If the tuple (0,10) represents the range of a valid pdf, then the next tuple (0,11) is also a valid pdf.

Openoffice pdf clipped edges