PDF, PS and DjVu

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This article covers software to view, edit and convert PDF, PostScript (PS), DjVu (déjà vu) and XPS files.

Engines

  • DjVuLibre — Suite to create, manipulate and view DjVu documents.
https://djvu.sourceforge.net/ || djvulibre
  • Ghostscript — Interpreter for PostScript and PDF. Provides the gs(1) command-line interface, see also /usr/share/doc/ghostscript/*/Use.htm (online), along with many wrapper scripts like ps2pdf and pdf2ps.
https://ghostscript.com/ || ghostscript
  • libgxps — GObject based library for handling and rendering XPS documents.
https://wiki.gnome.org/Projects/libgxps || libgxps
  • libspectre — Small library for rendering Postscript documents.
https://www.freedesktop.org/wiki/Software/libspectre || libspectre
  • Mupdf — MuPDF is a lightweight PDF, XPS, and EPUB viewer, consisting of a software library, command line tools, and viewers.
https://mupdf.com/ || libmupdf
https://poppler.freedesktop.org/ || poppler

Viewers

Framebuffer

  • fbgs — Poor man's PostScript/pdf viewer for the linux framebuffer console.
https://www.kraxel.org/blog/linux/fbida/ || fbida
  • fbpdf — Small framebuffer PDF and DjVu viewer based on MuPDF, with Vim keybindings and written in C
https://repo.or.cz/w/fbpdf.git || fbpdf-gitAUR
  • jfbview — Framebuffer PDF and image viewer. Features include Vim-like controls, zoom-to-fit, a TOC (outline) view and fast multi-threaded rendering.
https://github.com/jichu4n/jfbview || jfbviewAUR

Graphical

Note: Some web browsers can display PDF files, for example with PDF.js.
  • apvlv — Lightweight document viewer with Vim keybindings using GTK libraries. Supports PDF, DjVu, EPUB, HTML and TXT.
https://naihe2010.github.io/apvlv/ || apvlvAUR
  • Atril — Simple multi-page document viewer for MATE. Supports DjVu, DVI, EPS, EPUB, PDF, PostScript, TIFF, XPS and Comicbook.
https://github.com/mate-desktop/atril || atril
  • CorePDF — Simple lightweight PDF viewer based on Qt and poppler. Part of C-Suite.
https://cubocore.gitlab.io/ || corepdfAUR
  • Deepin Document Viewer — A simple PDF and DjVu reader, supporting bookmarks, highlights and annotations.
https://github.com/linuxdeepin/deepin-reader || deepin-reader
  • DjView — Viewer for DjVu documents.
https://djvu.sourceforge.net/djview4.html || djview
  • ePDFView — Lightweight PDF document viewer using the Poppler and GTK libraries. Development stopped.
http://freecode.com/projects/epdfview || epdfview-gitAUR
https://www.gnu.org/software/emacs/ || emacs
  • Evince — Document viewer for GNOME using GTK. Supports DjVu, DVI, EPS, PDF, PostScript, TIFF, XPS and Comicbook. Part of gnome.
https://wiki.gnome.org/Apps/Evince || evince
https://www.foxitsoftware.com/pdf-reader/ || foxitreaderAUR
  • gv — Graphical user interface for the Ghostscript interpreter that allows to view and navigate through PostScript and PDF documents.
https://www.gnu.org/software/gv/ || gvAUR
  • llpp — Very fast PDF reader based off of MuPDF, that supports continuous page scrolling, bookmarking, and text search through the whole document.
https://repo.or.cz/w/llpp.git || llppAUR
  • MuPDF — Very fast EPUB, FictionBook, PDF, XPS and Comicbook viewer written in portable C. Features CJK font support and vim-like bindings.
https://mupdf.com/ || mupdf
  • Okular — Universal document viewer for KDE. Supports CHM, Comicbook, DjVu, DVI, EPUB, FictionBook, Mobipocket, ODT, PDF, Plucker, PostScript, TIFF and XPS.
https://okular.kde.org/ || okular
  • PDF4QT — Open source PDF editor.
https://jakubmelka.github.io/ || pdf4qt-gitAUR
  • pdfpc — Presenter console with multi-monitor support for PDF files.
https://pdfpc.github.io/ || pdfpc
  • qpdfview — Tabbed document viewer. It uses Poppler for PDF support, libspectre for PS support, DjVuLibre for DjVu support, CUPS for printing support and the Qt toolkit for its interface.
https://launchpad.net/qpdfview || qpdfviewAUR
  • Sioyek — Lightweight PDF viewer based on MuPDF with features designed for viewing research papers and technical books, e.g., marking, bookmarking, highlighting, searchable command palette, jumping to references, and more.
https://sioyek.info/ || sioyekAUR
  • Xpdf — Viewer that can decode LZW and read encrypted PDFs.
https://www.xpdfreader.com/ || xpdf
  • Xreader — Document viewer part of the X-Apps Project. Supports DjVu, DVI, EPUB, PDF, PostScript, TIFF, XPS, Comicbook.
https://github.com/linuxmint/xreader/ || xreader
  • Zathura — Highly customizable and functional document viewer (plugin based). Supports PDF, DjVu, PostScript and Comicbook.
https://pwmt.org/projects/zathura/ || zathura

Comparison

The factual accuracy of this article or section is disputed.

Reason: Filling out PDF forms seem to be broken in MuPDF and llpp. (Discuss in Talk:PDF, PS and DjVu)
Name PDF PostScript DjVu XPS PDF forms PDF Annotation Non-rectangle selection License
Adobe Reader Custom Yes Yes proprietary
apvlv Poppler DjVuLibre No No (not by default, at least) GPLv2
Atril Poppler libspectre DjVuLibre libgxps Yes GPLv2
DjView DjVuLibre GPLv2
Emacs Ghostscript1 DjVuLibre1 No Yes Yes GPLv3
Emacs pdf-tools Poppler Yes Yes GPLv3
ePDFView Poppler No GPLv2
Evince Poppler libspectre DjVuLibre libgxps Yes Yes Yes GPLv2
Foxit Reader Custom Yes Yes Yes proprietary
gv Ghostscript No GPLv3
llpp libmupdf libmupdf Yes GPLv3
MuPDF Custom Custom Yes (mupdf-gl) Yes (mupdf-gl) Yes (mupdf-gl) AGPLv3
Okular Poppler libspectre DjVuLibre Custom Yes Yes Yes GPL, LGPL
PDF4QT Custom No Yes Yes LGPLv3
pdfpc Poppler No GPLv2
qpdfview Poppler libspectre1 DjVuLibre1 Yes Yes GPLv2
Xpdf Custom No GPLv3
Xreader Poppler libspectre1 DjVuLibre1 libgxps1 Yes Yes Yes GPLv2
Zathura libmupdf1 / Poppler1 libspectre1 DjVuLibre1 libmupdf1 No No Yes zlib
  1. Optional dependency needs to be installed

PDF forms

The PDF forms column in the above table refers to AcroForms support. If you do not need your input to be directly extractable from the PDF, you can also use the applications in #Graphical PDF editing to put text on top of a PDF. PDF forms can be created with LibreOffice Writer (View > Toolbars > Form Controls) and the advanced PDF editors.

The proprietary and deprecated XFA format for forms is not fully supported by Poppler[1][2] and only supported by Adobe Reader and Master PDF Editor.

Alternatively, web browsers such as Firefox or Chromium feature a built-in PDF viewer capable of filling out forms.

Graphical PDF editing

Editors that can import PDF files

  • Scribus can import and export PDF; text is imported as polygons.[3]
  • LibreOffice Draw can import and export PDF; text is imported as text; embedded fonts are substituted.[4][5]
  • Inkscape can import a single page from a PDF and export to PDF; text is imported as cloned glyphs or text; with the latter embedded fonts are substituted.
  • Graphics editors like GIMP and krita can also import and export PDFs at the cost of rasterization.

Basic editors

  • flpsed — A PostScript and PDF annotator, only supports text boxes.
https://flpsed.org/flpsed.html || flpsedAUR
  • HandyOutliner for DjVu / PDF — Make easier and faster the process of creating bookmarks for DjVu and PDF documents.
https://handyoutlinerfo.sourceforge.net || handyoutliner-binAUR
  • jPDF Tweak — Java Swing application that can combine, split, rotate, reorder, watermark, encrypt, sign, and otherwise tweak PDF files.
https://jpdftweak.sourceforge.net/ || jpdftweakAUR
  • PDF Arranger — Helps merge or split pdf documents and rotate, crop and rearrange pages. It is a maintained fork of PDF-Shuffler.
https://github.com/jeromerobert/pdfarranger || pdfarranger
  • PDF Chain — GTK front-end for PDFtk, written in C++, supporting concatenation, burst, watermarks, attaching files and more.
http://pdfchain.sourceforge.net/ || pdfchainAUR
  • PdfJumbler — Simple tool to rearrange, merge, delete and rotate pages in PDF files.
https://github.com/mgropp/pdfjumbler || pdfjumblerAUR
  • PDF Mix Tool — Qt front-end for PoDoFo, written in C++, supports splitting, merging, rotating and mixing PDF files.
https://scarpetta.eu/pdfmixtool/ || pdfmixtool
  • PDFsam — Open source application, written in Java, supports merging, splitting and rotating.
https://pdfsam.org/ || pdfsamAUR
  • PDF Slicer — Simple application to extract, merge, rotate and reorder pages of PDF documents.
https://junrrein.github.io/pdfslicer/ || pdfslicer
  • PDF Tricks — Simple, efficient application for small manipulations in PDF files using Ghostscript.
https://github.com/muriloventuroso/pdftricks || pdftricks

Cropping tools

  • briss — Java GUI to crop pages of PDF documents to one or more regions selected.
https://sourceforge.net/projects/briss/ || brissAUR
  • krop — Simple graphical tool to crop the pages of PDF files.
https://arminstraub.com/software/krop || kropAUR
  • pdfCropMargins — Automatically crops the margins of PDF files.
https://github.com/abarker/pdfCropMargins || pdfcropmarginsAUR
  • PdfHandoutCrop — Tool to crop pdf handout with multiple pages per sheet.
https://cges30901.github.io/pdfhandoutcrop/ || pdfhandoutcropAUR

Advanced editors

  • Master PDF Editor — Functional proprietary PDF editor. Latest version free for non-commercial use. The -free package is outdated but lacks a watermark.
https://code-industry.net/free-pdf-editor/ || masterpdfeditorAUR, masterpdfeditor-freeAUR
  • PDF Studio — All-in-one proprietary PDF editor similar to Adobe Acrobat.
https://www.qoppa.com/pdfstudio/ || pdfstudio-binAUR

Comparison of advanced editors

Name Cost (USD, lifetime) Page Labels Form Designer Content Editing (Text and Images) Optimize PDFs Digitally Sign PDFs License
Master PDF Editor 85.34 No Yes Yes Yes Yes proprietary
Qoppa PDF Studio Standard 99 Yes No No No No proprietary
Qoppa PDF Studio Pro 139 Yes Yes Yes Yes Yes proprietary

PDF tools

See also Ghostscript.

  • Camelot — Camelot: PDF Table Extraction for Humans.
https://github.com/atlanhq/camelot || python-camelotAUR, python-camelot-gitAUR
  • Coherent PDF — Proprietary non-free command line tools to manipulate PDF files including merge, encrypt, decrypt, scale, crop, rotate, bookmarks, stamp, logos, page numbers.
https://community.coherentpdf.com/ || cpdfAUR
  • DiffPDF — Compare the text or the visual appearance of each page in two PDF files.
https://gitlab.com/eang/diffpdf || diffpdf
  • mupdf-tools — Tools developed as part of MuPDF, contains mutool(1) and muraster.
https://mupdf.com || mupdf-tools
  • pdfcpu — Command-line tool to create and modify PDFs.
https://github.com/pdfcpu/pdfcpu || pdfcpu-binAUR
  • pdfgrep — Commandline utility to search text in PDF files.
https://pdfgrep.org/ || pdfgrep
  • pdfjam — Can be used to n-up, join, rotate and flip PDFs and arrange them into a format suitable for book binding.
https://github.com/DavidFirth/pdfjam || texlive-binextra
  • PDFMiner — PDFMiner is a text extraction tool for PDF documents. Not actively maintained as of 2020.
https://github.com/euske/pdfminer || pdfminerAUR
  • pdfminer.six — Community maintained fork of pdfminer.
https://github.com/pdfminer/pdfminer.six || python-pdfminer
  • pdf2svg — Convert PDF files to SVG files.
http://www.cityinthesky.co.uk/opensource/pdf2svg/ || pdf2svg
  • PDFtk — Simple tool for doing everyday things with PDF documents.
https://gitlab.com/pdftk-java/pdftk || pdftk
  • QPDF — Content-preserving PDF transformation system.
https://github.com/qpdf/qpdf || qpdf
  • Stapler — Light alternative to PDFtk using the PyPDF2 library.
https://github.com/hellerbarde/stapler || staplerAUR, stapler-gitAUR
  • Tabula — Tabula is a tool for liberating data tables trapped inside PDF files.
https://tabula.technology || tabulaAUR, tabula-javaAUR
  • verapdf — A purpose-built, open source, file-format validator covering all PDF/A and PDF/UA parts and conformance levels.
https://verapdf.org || verapdfAUR

Command snippets

Create a PDF from images

With GraphicsMagick:

$ gm convert 1.jpg 2.jpg 3.jpg out.pdf

With ImageMagick:

$ magick convert 1.jpg 2.jpg 3.jpg out.pdf

Note that ImageMagick's output is lossy. For lossless PDF creation from jpeg, use img2pdf.

Concatenate PDFs

With Ghostscript:

$ gs -dNOPAUSE -sDEVICE=pdfwrite -sOUTPUTFILE=out.pdf -dBATCH 1.pdf 2.pdf 3.pdf

With PDFtk:

$ pdftk 1.pdf 2.pdf 3.pdf cat output out.pdf

With Poppler:

$ pdfunite 1.pdf 2.pdf 3.pdf out.pdf

With QPDF:

$ qpdf --empty --pages 1.pdf 2.pdf 3.pdf -- out.pdf

Extract text from PDF

With Poppler and maintaining the layout:

$ pdftotext -layout in.pdf out.txt

See also pdftotext(1).

Decrypt a PDF

This section lists commands to decrypt a PDF to an unencrypted file. Note that most PDF viewers also support encrypted PDFs.

With PDFtk:

$ pdftk in.pdf input_pw password output out.pdf

With Poppler to PostScript:

$ pdftops -upw password in.pdf out.ps

With QPDF:

$ qpdf --decrypt --password=password in.pdf out.pdf
Tip: Forgotten passwords might be recovered with pdfcrack, see pdfcrack(1).

Encrypt a PDF

The user password is used for encryption, the owner password to restrict operations once the document is decrypted, for more information, see Wikipedia:PDF#Encryption and signatures.

With PDFtk:

$ pdftk in.pdf output out.pdf user_pw password

With PoDoFo:

$ podofoencrypt -u user_password -o owner_password in.pdf out.pdf

With QPDF:

$ qpdf --encrypt user_password owner_password key_length -- in.pdf out.pdf

where key_length can be 40, 128 or 256.

Extract images from a PDF

With poppler, saving images as JPEG:

$ pdfimages infile.pdf -j outfileroot

Extract page range from PDF, split multipage PDF document

With Ghostscript as a single file[6]

$ gs -sDEVICE=pdfwrite -dNOPAUSE -dBATCH -dSAFER -dFirstPage=first -dLastPage=last -sOutputFile=outfile.pdf infile.pdf

With PDFtk as a single file:

$ pdftk infile.pdf cat first-last output outfile.pdf

With Poppler as separate files:

$ pdfseparate -f first -l last infile.pdf outfileroot-%d.pdf

With QPDF as a single file:

$ qpdf --empty --pages infile.pdf first-last -- outfile.pdf

With mutool as a single file:

$ mutool clean -g infile.pdf outfile.pdf first-last

Impose a PDF (nup)

PDF Imposition is the process by which multiple input pages are combined into one output page, layed out into a rowsxcolumns grid.

It can be done with pdfjam (notice that wrapper scripts such as pdfnup and pdfbook are deprecated):

$ pdfjam --nup rowsxcolumns input.pdf --outfile output.pdf

or with pdfsak:

$ pdfsak --input-file input.pdf --output output.pdf --nup rows columns

Inspect metadata

With ExifTool:

$ exiftool -All file.pdf

With Poppler:

$ pdfinfo file.pdf

Remove metadata

Using ExifTool

With ExifTool:

$ exiftool -All= -overwrite_original input.pdf
$ mv input.pdf /tmp/temp.pdf
$ qpdf --linearize /tmp/temp.pdf input.pdf

The linearize step is needed to prevent recovery of deleted metadata. See this SuperUser question and the related ExifTool forum thread.

Using pdftk

Many PDFs store document metadata using both an Info dictionary (old school) and an XMP stream (new school). This pdftk command remove the XMP stream from the PDF altogether. It does not remove the Info dictionary.

Note that objects inside the PDF might have their own, separate XMP metadata streams, and that this command does not remove those. It only removes the PDF’s document‐level XMP stream.

$ pdftk input.pdf drop_xmp output output.pdf

Reduce size of a PDF

PDF size can be reduced by setting an appropriate optimization or compression level.

With Ghostscript one of:

$ ps2pdf -dPDFSETTINGS=/screen in.pdf out.pdf

or

$ gs -dNOPAUSE -dBATCH -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/printer -sOutputFile=out.pdf in.pdf

For different settings see the documentation.

There is also shrinkpdfAUR, a script wrapping gs.

Rasterize a PDF

These commands will convert your PDF into images.

With GraphicsMagick to convert a specific page into an image file:

$ gm convert -density dpi infile.pdf[page] outfile.jpg

With ImageMagick to convert a specific page into an image file:

$ magick convert -density dpi infile.pdf[page] outfile.jpg

With ImageMagick to convert all pages into another PDF file composed by an image file per page:

$ magick convert -density dpi infile.pdf outfile.pdf
Warning: This will increase the file size of your PDF substantially. Use it for example if your printer is not able to print your PDF correctly.

With Poppler to convert all pages into one image file per page:

$ pdftoppm -jpeg -r dpi infile.pdf outfileroot

With Poppler to convert a specific page into an image file:

$ pdftoppm -jpeg -r dpi -f page -singlefile infile.pdf outfileroot

Split PDF pages

With mupdf-tools to split every page vertically into two pages:

$ mutool poster -y 2 in.pdf out.pdf

Can be used to undo simple imposition.

Add an image

Adding an image to any location in a PDF can be done

Details on these and other solutions can be found on StackExchange.

Add digital signature to PDF

jsignpdfAUR can digitally sign PDF files with X.509 certificates in GUI and CLI.

Readers such as Okular and MuPDF can sign PDFs with digital signatures. This requires a PFX certificate, which can be created with an OpenSSL command:

$ openssl req -x509 -days 365 -newkey rsa:2048 -keyout cert.pem -out cert.pem
$ openssl pkcs12 -export -in cert.pem -out cert.pfx

MuPDF users can then sign PDFs with the cert.pfx using the graphical interface, or its mutool-sign tool.

Okular users must import cert.pfx into a certificate store such as the one in the default Firefox profile.[7][dead link 2024-01-13 ⓘ] With Firefox this is done through Settings > Privacy & Security > View Certificates > Your Certificates > Import and selecting cert.pfx. Afterwards Okular will offer this certificate to be used when signing PDFs.

Libreoffice can also sign PDFs.[8]

Removing annotations from a PDF

With pdftk [9]:

$ pdftk in.pdf output - uncompress | sed '/^\/Annots/d' | pdftk - output out.pdf compress

With perl-cam-pdfAUR:

$ rewritepdf.pl -C in.pdf out.pdf

See https://superuser.com/a/1051543 for more information.

Add page numbers

With pdfsak:

$ pdfsak --input-file input.pdf --output output.pdf --text "\large \$page/\$pages" br 0.99 0.99 --latex-engine xelatex --font "Noto Regular"

Add page labels

Page labels are logical page numbers shown in the navigation bar of your PDF reader. They are useful for example if the first pages of the PDF are indices numbered with roman numbers (I, II, etc.), while the page numbered "1" corresponds to a PDF page greater than 1, and you want the page number shown in the navigation bar to corresponds to the page number shown in the physical page.

This should not be confused with adding page numbers into a physical page. See section 12.4.2 of PDF reference to better understand page labels.

  1. Using pagelabels-py, let's say we have a PDF named my_document.pdf, that has 12 pages.
    • Pages 1 to 4 should be labelled Intro I to Intro IV.
    • Pages 5 to 9 should be labelled 2 to 6.
    • Pages 10 to 12 should be labelled Appendix A to Appendix C
    • We can issue the following list of commands:
      $ python3 -m pagelabels --delete "my_document.pdf"
      $ python3 -m pagelabels --startpage 1 --prefix "Intro " --type "roman uppercase" "my_document.pdf"
      $ python3 -m pagelabels --startpage 5 --firstpagenum 2 "my_document.pdf"
      $ python3 -m pagelabels --startpage 10 --prefix "Appendix " --type "letters uppercase" "my_document.pdf" 
    • Note: pagelabels-py will convert your file to PDF 1.3 specification
  2. Using pdftk, create a metadata.txt file with labels:
    PageLabelBegin
    PageLabelNewIndex: 1
    PageLabelStart: 1
    PageLabelPrefix: Cover
    PageLabelNumStyle: NoNumber
    PageLabelBegin
    PageLabelNewIndex: 2
    PageLabelStart: 1
    PageLabelPrefix: Back Cover
    PageLabelNumStyle: NoNumber
    PageLabelBegin
    PageLabelNewIndex: 3
    PageLabelStart: 1
    PageLabelNumStyle: LowercaseRomanNumerals
    PageLabelBegin
    PageLabelNewIndex: 27
    PageLabelStart: 1
    PageLabelNumStyle: DecimalArabicNumerals 
    • Where:
      PageLabelBegin
      signal a new page label definition will follow
      PageLabelNewIndex
      is the PDF page index from which the numbering style applies, counting from one. The numbering style will continue until the next page label or, if there are no more page labels, until the end of the document.
      PageLabelStart
      is the starting number. For example, if you specify 5 here, the pages will be numbered 5, 6, 7, ...
      PageLabelPrefix
      a text to put before the number in page labels.
      PageLabelNumStyle
      can be DecimalArabicNumerals, UppercaseRomanNumerals, LowercaseRomanNumerals, UppercaseLetters, LowercaseLetters or NoNumber.
    • Then use:
      pdftk book.pdf update_info_utf8 metadata.txt output book-with-metadata.pdf

See this SuperUser question for more details.

Extract bookmarks

With pdftk:

$ pdftk file.pdf dump_data_utf8 | grep '^Bookmark'

With qpdf:

$ qpdf --json --json-key=outlines file.pdf

See https://unix.stackexchange.com/questions/143886/how-to-extract-bookmarks-from-a-pdf-file for more information.

Add bookmarks

With pdftk

Create a text file bookmark_definitions.txt with bookmark definitions in the following format:

BookmarkBegin
BookmarkTitle: Chapter 1
BookmarkLevel: 1
BookmarkPageNumber: 1
BookmarkBegin
BookmarkTitle: Chapter 1.1
BookmarkLevel: 2
BookmarkPageNumber: 2
BookmarkBegin
BookmarkTitle: Chapter 1.2
BookmarkLevel: 2
BookmarkPageNumber: 3
BookmarkBegin
BookmarkTitle: Chapter 1.3
BookmarkLevel: 2
BookmarkPageNumber: 4
BookmarkBegin
BookmarkTitle: Chapter 1.3.1
BookmarkLevel: 3
BookmarkPageNumber: 5
BookmarkBegin
BookmarkTitle: Chapter 2
BookmarkLevel: 1
BookmarkPageNumber: 6

Where

BookmarkBegin
signal a new bookmark definition
BookmarkTitle
the title of the bookmark
BookmarkLevel
the level of the bookmark in the hierarchy
BookmarkPageNumber
the page number the bookmark redirects to

In this example, the above file will create the following bookmark structure:

  • Chapter 1
    • Chapter 1.1
    • Chapter 1.2
    • Chapter 1.3
      • Chapter 1.3.1
  • Chapter 2

Apply the bookmarks with the following command:

$ pdftk input.pdf update_info_utf8 bookmark_definitions.txt output output.pdf

Extract pages contained within a bookmark

To extract the pages contained within a bookmark, you can use pdf_extbook.

Remove blank pages

One can use the following script to remove blank pages form a PDF file (credit: SuperUser post):

#!/bin/sh

IN="$1"
filename=$(basename "${IN}")
filename="${filename%.*}"
PAGES=$(pdfinfo "$IN" | grep ^Pages: | tr -dc '0-9')

non_blank() {
	for i in $(seq 1 $PAGES); do
		PERCENT=$(gs -o - -dFirstPage=${i} -dLastPage=${i} -sDEVICE=ink_cov "$IN" | grep CMYK | nawk 'BEGIN { sum=0; } {sum += $1 + $2 + $3 + $4;} END { printf "%.5f\n", sum } ')
		if [ $(echo "$PERCENT > 0.001" | bc) -eq 1 ]; then
			echo $i
			#echo $i 1>&2
		fi
		echo -n . 1>&2
	done | tee "$filename.tmp"
	echo 1>&2
}

set +x
pdftk "${IN}" cat $(non_blank) output "${filename}_noblanks.pdf"

Use it like pdf_remove_blank_pages input.pdf.

The script needs pdftk, nawk and ghostscript.

Find fonts used in a PDF

The pdffonts(1) command (from poppler), can be used to find which fonts a PDF uses and if they have been embedded in it or not:

$ pdffonts file.pdf
name                                 type              encoding         emb sub uni object ID
------------------------------------ ----------------- ---------------- --- --- --- ---------
Times-Roman                          Type 1            Custom           no  no  no       8  0
Times-Italic                         Type 1            Standard         no  no  no       9  0
Times-Bold                           Type 1            Standard         no  no  no       7  0
Helvetica                            Type 1            Standard         no  no  no      34  0
Helvetica-Bold                       Type 1            Standard         no  no  no      35  0

This can be used when having issues displaying properly the text in a PDF, to determine if missing fonts or their metric-compatible equivalent need to be installed.

Repair broken PDF file

With ghostscript:

$ gs -o repaired.pdf -sDEVICE=pdfwrite -dPDFSETTINGS=/prepress corrupted.pdf

With poppler:

$ pdftocairo -pdf corrupted.pdf repaired.pdf

With mupdf-tools:

$ mutool clean corrupted.pdf repaired.pdf

Reference: https://superuser.com/q/278562

Convert PDF to PDF/A standard

With ghostscript:

$ gs -dPDFA -dBATCH -dNOPAUSE -sColorConversionStrategy=UseDeviceIndependentColor -sDEVICE=pdfwrite -dPDFACompatibilityPolicy=2 -sOutputFile=document_pdfa.pdf document.pdf

Reference: https://stackoverflow.com/a/56459053

Validate PDF/A compliance

Using verapdfAUR you can validate the compliance of your PDF to different flavours of the PDF/A standard:

$ verapdf --flavour 1a --format text document.pdf

DjVu tools

  • DjVuLibre provides many command-line tools, like ddjvu(1) for example.
  • img2djvu — Single-pass DjVu encoder based on DjVu Libre and ImageMagick.
https://github.com/ashipunov/img2djvu || img2djvu-gitAUR
  • pdf2djvu — Creates DjVu files from PDF files.
https://jwilk.net/software/pdf2djvu || pdf2djvuAUR

Convert DjVu to images

Break Djvu into separate pages:

$ djvmcvt -i input.djvu /path/to/out/dir output-index.djvu

Convert Djvu pages into images:

$ ddjvu --format=tiff page.djvu page.tiff

Convert Djvu pages into PDF:

$ ddjvu --format=pdf inputfile.djvu ouputfile.pdf

You can also use --page to export specific pages:

$ ddjvu --format=tiff --page=1-10 input.djvu output.tiff

this will convert pages from 1 to 10 into one tiff file.

Processing images

You can use scantailor-advanced to:

  • fix orientation
  • split pages
  • deskew
  • crop
  • adjust margins

Make DjVu from images

There is a useful script img2djvu-gitAUR.

$ img2djvu -c1 -d600 -v1 ./out

it will create 600 DPI out.djvu from all files in ./out directory.

Alternatively, you can try didjvuAUR, which seems to create smaller files especially on images with well defined background.

PostScript tools

  • pstotext — Converts PostScript files to text.
https://www.cs.wisc.edu/~ghost/doc/pstotext.htm || pstotextAUR

ps2pdf

ps2pdf is a wrapper around ghostscript to convert PostScript to PDF:

$ ps2pdf -sPAPERSIZE=a4 -dOptimize=true -dEmbedAllFonts=true YourPSFile.ps

Explanation:

  • with -sPAPERSIZE=something you define the paper size. For valid PAPERSIZE values, see [10][dead link 2022-09-22 ⓘ].
  • -dOptimize=true lets the created PDF be optimised for loading.
  • -dEmbedAllFonts=true makes the fonts look always nice.
Note: You cannot choose the paper orientation in ps2pdf. If your input PS file is healthy, it already contains the orientation information. If you are trying to use an Encapsulated PS file, you will have problems, if it does not fit in the -sPAPERSIZE you specified, because EPS files usually do not contain paper orientation information. A workaround is creating a new paper in ghostscript settings (call it e.g. "slide") and use it as -sPAPERSIZE=slide.

Libraries

C/C++

  • libharu — C library for generating PDF documents.
https://github.com/libharu/libharu || libharu, Lua binding: lua-hpdfAUR
  • PoDoFo — A C++ library to work with the PDF file format.
https://podofo.sourceforge.net || podofo

Python

  • borb — borb is a library for reading, creating and manipulating PDF files in python.
https://borbpdf.com/, https://github.com/jorisschellekens/borb || not packaged? search in AUR
  • pdfrw — A pure Python library that reads and writes PDFs.
https://github.com/pmaupin/pdfrw || python-pdfrw
  • PyPDF — A pure-Python library built as a PDF toolkit.
https://github.com/py-pdf/pypdf || python-pypdf
  • PyX — Python library for the creation of PostScript and PDF files.
http://pyx.sourceforge.net || python-pyx
  • ReportLab — A proven industry-strength PDF generating solution
https://www.reportlab.com/ || python-reportlab

Java

  • iText Core — iText is a more versatile, programmable and enterprise-grade PDF solution that allows you to embed its functionalities within your own software for digital transformation.
https://itextpdf.com/products/itext-core || itext-rups-binAUR
  • OpenPDF — OpenPDF is a free Java library for creating and editing PDF files with a LGPL and MPL open source license. OpenPDF is based on a fork of iText.
https://github.com/LibrePDF/OpenPDF || not packaged? search in AUR

See also