pdf-2-images

Clojure wrapper for the PDFBox that converts a page range of a PDF document to images.

Why forked? It seems the maintainer of the original repo is no longer available or not willing to commit new changes.

Quickstart

For installation, add the following dependency to your project.clj file:

[org.clojars.roboli/pdf-2-images "1.0.0"]

Import namespace example:

(ns hello-world.core
  (:require [pdf-2-images.core :as pdf]))

You can choose one of the three predefined handlers, that will let you convert your PDF's page or pages to an image:

• image-to-image: Returns a list of buffered images.
• image-to-byte-array: Returns a list of byte arrays, one per image.
• image-to-file: Returns a list of paths (strings), one per image.

Or pass your own custom handler, more below.

Basic usage example:

(let [image-paths (pdf/pdf-2-images pdf/image-to-file :pdf-file (clojure.java.io/file "path-to-pdf"))]
  (prn (str "Images count: " (count image-paths)))
  (map prn image-paths))

;; "Images count: n"
;; "path-to-image-0"
;; "path-to-image-1"
;; ...
;; "path-to-image-n-1"

The same with key-value pair parameter - pathname will be used if pdf-file is not specified (= nil):

(let [image-paths (pdf/pdf-2-images pdf/image-to-file :pathname "path-to-pdf")]
  (prn (str "Images count: " (count image-paths)))
  (map prn image-paths))

;; "Images count: n"
;; "path-to-image-0"
;; "path-to-image-1"
;; ...
;; "path-to-image-n-1"

With-options usage example:

(let [image-paths (pdf/pdf-2-images pdf/image-to-file
                                    :pdf-file (clojure.java.io/file "path-to-pdf")
                                    :start-page 0
                                    :end-page 1
                                    :dpi 100
                                    :quality 1
                                    :ext "jpg")]
  (prn (str "Images count: " (count image-paths)))
  (map prn image-paths))

;; "Images count: 2"
;; "path-to-image-0"
;; "path-to-image-1"

Usage

(pdf-2-images handler :option-1-key option-1-val :option-2-key option-2-val ...)

Where options:

• :page: Page to convert to an image, takes precedence over :start-page and :end-page
• :start-page: The start page, defaults to 0
• :end-page: The end page, defaults to PDF's pages length - 1 or Integer/MAX_VALUE
• :dpi: Screen resolution, defaults to 300
• :quality: Quality to be used when compressing the image (0 < quality < 1), defaults to 1
• :ext: The target file format, defaults to png
• :pdf-file: A PDF java.io.File, takes precedence over :pathname
• :pathname: Path to the PDF file, used if :pdf-file is not specified (= nil)

Custom Handlers

Basically, pass in a function expecting a map:

(defn your-custom-handler [m] ...)

Where m has the following keys with a corresponding value:

• :image: A buffered image of the current page
• :image-index: The current page index
• :ext: The image file extension
• :dpi: Screen resolution
• :quality: Quality to be used when compressing the image
• :base-path: The PDF file base path

There are no constraints for the returned value.

Examples

• Webserver-convert: Try using pdf-2-images within a web server to convert your PDFs to images.

License

• Copyright © 2016 Igor Moiseyenko
• Copyright © 2023 Roberto Oliveros

Distributed under the Eclipse Public License version 1.0.