4 ms·

i don't know about djvu format, but being in the process of writing a pdf parser atm i can tell you there's definitely some room for a simpler file format than

by bsaul 8y ago

i don't know about djvu format, but being in the process of writing a pdf parser atm i can tell you there's definitely some room for a simpler file format than pdf. The size of the specification is daunting, and i still encounter weird behaviors for some documents on some major platform's reader ( and now that i've read part of the spec i definitely understand why). Something a little more up to date and more focused on today's technologies would be really nice.

jacquesm 8y ago
Interesting, are you starting from scratch or building on poppler or something like it? I am writing a PDF parser too and am building on top of poppler to do the heavy lifting.
- bsaul 8y ago
  I’m building something on ios to extract text only from pdf along with some basic rendering features ( text position and font info, something that big commercial libraries don’t provide curiously ). So i’m using apple core foundation lib to do the basic parsing and use a project called pdfkitten as a starting point for font to unicode decoding and text positionning. I also plan to add obvious heuristics for « words » building later on as well as a global index for all the rendered blocks ( all done in swift). Images, forms, etc, are completely out of the scope. It’s a very specific and ( hopefully) narrow need and is the only reason i’m starting this project in the first place.
  - magduf 8y ago
    This is a little off-topic but you seem like a good person to ask: Do you know a way to crop a PDF? Basically, if I have a PDF of a single letter-size page with a 6x9 label on it, and I'd like to crop it down to that 6x9 label only, is there a way to do this? I've been looking into this with, for instance, the poppler library, and haven't found anything.
    - bsaul 8y ago
      i suppose you mean you want to do that with code, and not using a tool ( because my first search would be for command line tool or automation software using a combination of pdf to jpg then crop then export in pdf). You could parse the pdf for that bit of text then simply recreate a new one with the correct size. But it depends a lot of how that label is printed ( using one block for the whole label or one per letter). Basically it's a lot of work or not depending on the number of cases you need to deal with. I know python has a python miner library, you may want to try that
      - magduf 8y ago
        Yep, I'm looking for a way to do that with automation somehow, either code or even a command-line tool, just not manually with a GUI. My issue with JPG conversion is the lossiness factor introduced there; I'm trying to avoid that. There should only be one case: a single label on a letter-size page surrounded by a lot of whitespace. I'll check out that miner library; thanks!!
  - jacquesm 8y ago
    Thank you, I missed your answer when it first was given.

by bsaul 8y ago

jacquesm 8y ago

Interesting, are you starting from scratch or building on poppler or something like it? I am writing a PDF parser too and am building on top of poppler to do the heavy lifting.

bsaul 8y ago
I’m building something on ios to extract text only from pdf along with some basic rendering features ( text position and font info, something that big commercial libraries don’t provide curiously ). So i’m using apple core foundation lib to do the basic parsing and use a project called pdfkitten as a starting point for font to unicode decoding and text positionning. I also plan to add obvious heuristics for « words » building later on as well as a global index for all the rendered blocks ( all done in swift). Images, forms, etc, are completely out of the scope. It’s a very specific and ( hopefully) narrow need and is the only reason i’m starting this project in the first place.
- magduf 8y ago
  This is a little off-topic but you seem like a good person to ask: Do you know a way to crop a PDF? Basically, if I have a PDF of a single letter-size page with a 6x9 label on it, and I'd like to crop it down to that 6x9 label only, is there a way to do this? I've been looking into this with, for instance, the poppler library, and haven't found anything.
  - bsaul 8y ago
    i suppose you mean you want to do that with code, and not using a tool ( because my first search would be for command line tool or automation software using a combination of pdf to jpg then crop then export in pdf). You could parse the pdf for that bit of text then simply recreate a new one with the correct size. But it depends a lot of how that label is printed ( using one block for the whole label or one per letter). Basically it's a lot of work or not depending on the number of cases you need to deal with. I know python has a python miner library, you may want to try that
    - magduf 8y ago
      Yep, I'm looking for a way to do that with automation somehow, either code or even a command-line tool, just not manually with a GUI. My issue with JPG conversion is the lossiness factor introduced there; I'm trying to avoid that. There should only be one case: a single label on a letter-size page surrounded by a lot of whitespace. I'll check out that miner library; thanks!!
- jacquesm 8y ago
  Thank you, I missed your answer when it first was given.