4 ms·

I don't see how PDF is not a true digital format. I guess the powers that be understand something that you don't.

tashbarg 4y ago
I guess parent is focusing on the point, that PDFs can render as perfectly human-readable documents, but can be completely non-machine readable at the same time.
jimjimjim 4y ago
PDF is a true digital format. In the same way as a zip file is. A pdf page can be made a many many different ways. It depends on what use you are targeting. You want 1:1 digital replica of a page? scan the page as a tiff and add it to a page as an image. Or you could just add the text to the page and the font. Or if you want to mess with people or you are a cad application you draw text as thousands of little lines.
viraptor 4y ago
PDFs are not useful for any processing. They represent things you want to print, but not search, understand, analyse, etc. Even those with text actually attached / extractable have no structure. "Selecting blocks of text" involves guessing which order the lines go in, depending on their location / distance from other lines. Compare to having for example "<recipient-address>...</...>" from which you can still generate the printed version.
- xwolfi 4y ago
  Well usually the pdf processing I did always assumed I had a paper of x by y cm, and a mask I d move around "make a 10 by 20 cm rectangle at position (100,200), what s in that rectangle" basically. There's a structure, just not tag-based but position-based ? Ofc, if humans shit around and change it, you're fucked with versionning your masks, but usually they print from form templates themselves. As I used to say to my colleagues bemoaning this inconvenient analogue bridge: "if you can read it coherently as a human, we can parse it". We have to accept that administrations communicate via geometry and not semantic, and adapt while we also try to convince them to give structured tagging a chance. But they need a critical mass of their documentation pipeline to be machine-read before they even accept to discuss it.
  - 411111111111111 4y ago
    So your point is that pdf is a shit format that needs a custom parser for each document type before it can be used for anything but print...? I'm really confused here, it seems we all agree that pdf is a bad format?
    - kaba0 4y ago
      I don’t know, it seems to be a format that does its intended job just fine. What’s next, will we hate txt as that’s not a good for spreadsheets?
    - xwolfi 4y ago
      It's as shit a format as non-UTF strings, yet it's everywhere and we must adapt, is my point. We can adapt to scanned documents before all documents are semantically tagged, just like we have to adapt to non standard ascii extensions in non English countries, is my point.
  - viraptor 4y ago
    And by "if humans shit around and change it" you mean things that regularly happen and need to be accounted for like moving the physical location to a place with the address one line longer, or getting a new partner which changes the letterhead, or adding extra information required by legal, or ...
- Someone 4y ago
  > "Selecting blocks of text" involves guessing which order the lines go in, depending on their location / distance from other lines. If you create your own PDFs, you can make sure they contain both information about reading order and the mapping from glyphs back to UTF-8 text by creating an accessible PDF (aka a “tagged PDF”) I think most modern word processors can create such PDFs. MS Word definitely can (https://support.microsoft.com/en-us/office/create-accessible-pdfs-064625e0-56ea-4e16-ad71-3aa33bb4b7ed https://support.microsoft.com/en-us/office/create-accessible...). > Compare to having for example "<recipient-address>...</...>" from which you can still generate the printed version. Generating _a_ printed version is easy; generating _the_ printed version, guaranteeing 100% reproducibility isn’t. To get the exact same layout, you’ll have to guarantee to use the same fonts (difficult, as OSes can update their fonts, possibly tweaking a glyph, a kerning table or anything else that can affect layout) and, basically, never fix bugs in your PDF generation flow. That’s why many people keep both the structured source data (e.g. in json or xml) and the generated PDF.
  - viraptor 4y ago
    > creating an accessible PDF (aka a “tagged PDF”) I don't think I've seen a tagged PDF in the wild... ever. I'm sure they exist, but I'm doing a lot of stuff with PDFs in the healthcare context and this tech may as well not exist for me. To the point that most apps will support embedding a bad PDF in an HL7 file just to add metadata. > That’s why many people keep both the structured source data (e.g. in json or xml) and the generated PDF. They totally should. No dispute.
- hoosieree 4y ago
  > PDFs are not useful for any processing. Oh my sweet summer child. https://rawgit.com/osnr/horrifying-pdf-experiments/master/breakout.pdf https://rawgit.com/osnr/horrifying-pdf-experiments/master/br...
  - viraptor 4y ago
    I mean processing the content in them, not self-modifying. Sure, you can embed scripts to make them interactive.
lxgr 4y ago
In that sense, a blurry, warped TIFF is a true digital format as well.

I guess parent is focusing on the point, that PDFs can render as perfectly human-readable documents, but can be completely non-machine readable at the same time.

jimjimjim 4y ago

PDF is a true digital format. In the same way as a zip file is. A pdf page can be made a many many different ways. It depends on what use you are targeting. You want 1:1 digital replica of a page? scan the page as a tiff and add it to a page as an image. Or you could just add the text to the page and the font. Or if you want to mess with people or you are a cad application you draw text as thousands of little lines.

viraptor 4y ago

PDFs are not useful for any processing. They represent things you want to print, but not search, understand, analyse, etc. Even those with text actually attached / extractable have no structure. "Selecting blocks of text" involves guessing which order the lines go in, depending on their location / distance from other lines. Compare to having for example "<recipient-address>...</...>" from which you can still generate the printed version.

xwolfi 4y ago
Well usually the pdf processing I did always assumed I had a paper of x by y cm, and a mask I d move around "make a 10 by 20 cm rectangle at position (100,200), what s in that rectangle" basically. There's a structure, just not tag-based but position-based ? Ofc, if humans shit around and change it, you're fucked with versionning your masks, but usually they print from form templates themselves. As I used to say to my colleagues bemoaning this inconvenient analogue bridge: "if you can read it coherently as a human, we can parse it". We have to accept that administrations communicate via geometry and not semantic, and adapt while we also try to convince them to give structured tagging a chance. But they need a critical mass of their documentation pipeline to be machine-read before they even accept to discuss it.
- 411111111111111 4y ago
  So your point is that pdf is a shit format that needs a custom parser for each document type before it can be used for anything but print...? I'm really confused here, it seems we all agree that pdf is a bad format?
  - kaba0 4y ago
    I don’t know, it seems to be a format that does its intended job just fine. What’s next, will we hate txt as that’s not a good for spreadsheets?
  - xwolfi 4y ago
    It's as shit a format as non-UTF strings, yet it's everywhere and we must adapt, is my point. We can adapt to scanned documents before all documents are semantically tagged, just like we have to adapt to non standard ascii extensions in non English countries, is my point.
- viraptor 4y ago
  And by "if humans shit around and change it" you mean things that regularly happen and need to be accounted for like moving the physical location to a place with the address one line longer, or getting a new partner which changes the letterhead, or adding extra information required by legal, or ...
Someone 4y ago
> "Selecting blocks of text" involves guessing which order the lines go in, depending on their location / distance from other lines. If you create your own PDFs, you can make sure they contain both information about reading order and the mapping from glyphs back to UTF-8 text by creating an accessible PDF (aka a “tagged PDF”) I think most modern word processors can create such PDFs. MS Word definitely can (https://support.microsoft.com/en-us/office/create-accessible-pdfs-064625e0-56ea-4e16-ad71-3aa33bb4b7ed https://support.microsoft.com/en-us/office/create-accessible...). > Compare to having for example "<recipient-address>...</...>" from which you can still generate the printed version. Generating _a_ printed version is easy; generating _the_ printed version, guaranteeing 100% reproducibility isn’t. To get the exact same layout, you’ll have to guarantee to use the same fonts (difficult, as OSes can update their fonts, possibly tweaking a glyph, a kerning table or anything else that can affect layout) and, basically, never fix bugs in your PDF generation flow. That’s why many people keep both the structured source data (e.g. in json or xml) and the generated PDF.
- viraptor 4y ago
  > creating an accessible PDF (aka a “tagged PDF”) I don't think I've seen a tagged PDF in the wild... ever. I'm sure they exist, but I'm doing a lot of stuff with PDFs in the healthcare context and this tech may as well not exist for me. To the point that most apps will support embedding a bad PDF in an HL7 file just to add metadata. > That’s why many people keep both the structured source data (e.g. in json or xml) and the generated PDF. They totally should. No dispute.
hoosieree 4y ago
> PDFs are not useful for any processing. Oh my sweet summer child. https://rawgit.com/osnr/horrifying-pdf-experiments/master/breakout.pdf https://rawgit.com/osnr/horrifying-pdf-experiments/master/br...
- viraptor 4y ago
  I mean processing the content in them, not self-modifying. Sure, you can embed scripts to make them interactive.

lxgr 4y ago

In that sense, a blurry, warped TIFF is a true digital format as well.