PDF

From Just Solve the File Format Problem
(Difference between revisions)
Jump to: navigation, search
m
(List of compression schemes)
Line 35: Line 35:
 
** http://en.wikipedia.org/wiki/AppleSingle_and_AppleDouble_formats
 
** http://en.wikipedia.org/wiki/AppleSingle_and_AppleDouble_formats
 
** http://tools.ietf.org/rfc/rfc1740.txt
 
** http://tools.ietf.org/rfc/rfc1740.txt
 +
 +
== Compression ==
 +
Images in PDF documents may use the following compression schemes:
 +
* [[LZW]]
 +
* Flate ([[zlib]])
 +
* [[Run-length encoding|RunLength]]
 +
* CCITTFax ([[CCITT Group 3]] and [[CCITT Group 4]])
 +
* [[JBIG2]]
 +
* DCT ([[JPEG]])
 +
* [[JPX]] (part of the [[JPEG2000]] standard)
  
 
== Software ==
 
== Software ==

Revision as of 20:08, 28 February 2013

File Format
Name PDF
Ontology
Extension(s) .pdf

PDF, portable document format, based on PostScript and originally from Adobe, has many subsets.

As well as the 'full function' ISO 32000-1:2008 (or PDF 1.7), there are also PDF/X, PDF/A, PDF/E, PDF/VT and PDF/UA, all of which are ISO specifications.

PDF profiles (formalized subsets) include the following:

  • PDF/A (optimized for preservation)
    • PDF/A-1 (ISO 19005-1:2005)
    • PDF/A-2 (ISO 19005-2:2011)
    • PDF/A-3 (ISO 19005-3:2012) (extends PDF/A-2 by allowing embedded files of any type)
  • PDF/E (ISO 24517-1:2008) (for engineering workflows)
  • PDF/UA (ISO 14289-1) (making documents accessible through assistive technologies)
  • PDF/VT (ISO 16612-2) (support for variable document printing)
  • PDF/X (support for prepress graphics exchange)
    • PDF/X-1 (ISO 15930-1:2001)
    • PDF/X-1a (ISO 15930-4:2003)
    • PDF/X-2 (ISO 15930-5:2003)
    • PDF/X-3 (ISO 15930-6:2003)
  • Tagged PDF

Also see: extension PDF

Contents

Identification

The majority of PDF files can be identified by a fixed header e.g. "%PDF-1.4", however, older documents have a number of variations.

  • Some can start with "%!PS-Adobe-N.n PDF-M.m" instead, as described here.
  • Since PDF 1.7, the major and minor version numbers have been fixed. i.e. the public version from Adobe after 1.7 was "1.7 Adobe Extension Level 3".
  • For the PDF/A families of formats, their conformance is declared via an embedded (XMP) metadata fragment.
  • Some older files from Mac OS may be wrapped up in the AppleSingle/AppleDouble formats. This is a general issue, so should perhaps be documented elsewhere. For more information, see:

Compression

Images in PDF documents may use the following compression schemes:

Software

  • Adobe Reader views PDF files, either as a standalone program or a browser plugin.
  • Firefox 19.0 includes a built-in PDF reader.

Sample files

References

Personal tools
Namespaces

Variants
Actions
Navigation
Toolbox