https://github.com/Yuras/pdf-toolbox

A collection of tools for processing PDF files in Haskell
https://github.com/Yuras/pdf-toolbox

haskell pdf

Last synced: 3 months ago
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A collection of tools for processing PDF files in Haskell

• Host: GitHub
• URL: https://github.com/Yuras/pdf-toolbox
• Owner: Yuras
• Created: 2013-02-13T21:35:47.000Z (over 11 years ago)
• Default Branch: master
• Last Pushed: 2024-05-29T18:41:25.000Z (5 months ago)
• Last Synced: 2024-07-20T21:43:50.866Z (4 months ago)
• Topics: haskell, pdf
• Language: Haskell
• Homepage:
• Size: 568 KB
• Stars: 180
• Watchers: 16
• Forks: 25
• Open Issues: 11
• Metadata Files:
  • Readme: README.md

Awesome Lists containing this project

• awesome-pdf - toolbox

README

        
pdf-toolbox

===========

[![Haskell CI](https://github.com/Yuras/pdf-toolbox/actions/workflows/build.yml/badge.svg)](https://github.com/Yuras/pdf-toolbox/actions/workflows/build.yml)

A collection of tools for processing PDF files

Features

--------

 * Written in Haskell

 * Parsing on demand. You don't need to parse or load into memory

the entire PDF file just to extract one image

 * Different levels of abstraction. You can inspect high level (catalog, page tree, pages)

or low level (xref, trailer, object) structure of PDF file.

You can even switch between levels of details on the fly.

 * Extremely fast and memory efficient when you need to inspect only part of the document

 * Resonably fast and memory efficient in general case

 * Text extraction with exact glyph positions

It can be used e.g. to implement text selection and copying in pdf viewer

 * Full support of xref streams and object streams

 * Supports editing of PDF files (incremental updates)

 * Basic support for PDF file generating

 * Encrypted PDF documents are partially supported

Still in TODO list

------------------

 * Linearized PDF files

 * Higher level API for incremental updates and PDF generating

Examples

--------

(Also see `examples` and `viewer` directories)

Inspect high level structure:

```haskell

import Control.Monad

import Pdf.Document

main =

  withPdfFile "input.pdf" $ \pdf -> do

    encrypted <- isEncrypted pdf

    when encrypted $ do

      ok <- setUserPassword pdf defaultUserPassword

      unless ok $

        fail "need password"

    doc <- document pdf

    catalog <- documentCatalog doc

    rootNode <- catalogPageNode catalog

    count <- pageNodeNKids rootNode

    print count

    -- the first page of the document

    page <- pageNodePageByNum rootNode 0

    -- extract text

    txt <- pageExtractText page

    print txt

    ...

```