PDF Tags

The tags listed in the PDF tables below are those which are used by ExifTool to extract meta information, but they are only a small fraction of the total number of available PDF tags.

When writing PDF files, ExifTool uses an increment update. This has the advantages of being fast and reversible. The original PDF can be easily recovered by deleting the PDF-update pseudo-group (with -PDF-update:all= on the command line). But there are two main disadvantages to this technique:

1) A linearized PDF file is no longer linearized after the update, so it must be subsequently re-linearized if this is required.

2) All metadata edits are reversible. While this would normally be considered an advantage, it is a potential security problem because old information is never actually deleted from the file.

Tag IDTag Name WritableValues / Notes
'Info' Info - --> PDF Info Tags
'Root' Root - --> PDF Root Tags

PDF Info Tags

As well as the tags listed below, the PDF specification allows for user-defined tags to exist in the Info dictionary. These tags, which should have corresponding XMP-pdfx entries in the XMP of the PDF XML Metadata object, are also extracted by ExifTool.

Writable specifies the value format, and may be string, date, integer, real, boolean or name for PDF tags.

Tag IDTag Name WritableValues / Notes
'AAPL:Keywords' AppleKeywords string+ (keywords written by Apple utilities, although they seem to use PDF:Keywords when reading)
'Author' Author string  
'CreationDate' CreateDate date  
'Creator' Creator string  
'Keywords' Keywords string+  
'ModDate' ModifyDate date  
'Producer' Producer string  
'Subject' Subject string  
'Title' Title string  
'Trapped' Trapped string!  

PDF Root Tags

This is the PDF document catalog.

Tag IDTag Name WritableValues / Notes
'Metadata' Metadata - --> PDF Metadata Tags
'Pages' Pages - --> PDF Pages Tags
'Version' PDFVersion N  

PDF Metadata Tags

Tag IDTag Name WritableValues / Notes
'XML_stream' XMP - --> XMP Tags

PDF Pages Tags

Tag IDTag Name WritableValues / Notes
'Count' PageCount N  
'Kids' Kids - --> PDF Kids Tags

PDF Kids Tags

Tag IDTag Name WritableValues / Notes
'Metadata' Metadata - --> PDF Metadata Tags
'PieceInfo' PieceInfo - --> PDF PieceInfo Tags
'Resources' Resources - --> PDF Resources Tags

PDF PieceInfo Tags

Tag IDTag Name WritableValues / Notes
'AdobePhotoshop' AdobePhotoshop - --> PDF AdobePhotoshop Tags
'Illustrator' Illustrator - --> PDF Illustrator Tags

PDF AdobePhotoshop Tags

Tag IDTag Name WritableValues / Notes
'Private' Private - --> PDF Private Tags

PDF Private Tags

Tag IDTag Name WritableValues / Notes
'ImageResources' ImageResources - --> PDF ImageResources Tags

PDF ImageResources Tags

Tag IDTag Name WritableValues / Notes
'_stream' _stream - --> Photoshop Tags

PDF Illustrator Tags

Tag IDTag Name WritableValues / Notes
'Private' Private - --> PDF AIPrivate Tags

PDF AIPrivate Tags

Tag IDTag Name WritableValues / Notes
'AIMetaData' AIMetaData - --> PDF AIMetaData Tags
'AIPrivateData' AIPrivateData - --> PostScript Tags
(the ExtractEmbedded option enables information to be extracted from embedded PostScript documents in the AIPrivateData stream)
'ContainerVersion' ContainerVersion N  
'CreatorVersion' CreatorVersion N  
'RoundTripVersion' RoundTripVersion N  

PDF AIMetaData Tags

Tag IDTag Name WritableValues / Notes
'_stream' _stream - --> PostScript Tags

PDF Resources Tags

Tag IDTag Name WritableValues / Notes
'ColorSpace' ColorSpace - --> PDF ColorSpace Tags

PDF ColorSpace Tags

Tag IDTag Name WritableValues / Notes
'DefaultRGB' DefaultRGB - --> PDF DefaultRGB Tags

PDF DefaultRGB Tags

Tag IDTag Name WritableValues / Notes
'ICCBased' ICCBased - --> PDF ICCBased Tags

PDF ICCBased Tags

Tag IDTag Name WritableValues / Notes
'_stream' _stream - --> ICC_Profile Tags

(This document generated automatically by Image::ExifTool::BuildTagLookup)
Last revised Oct 27, 2009

<-- ExifTool Tag Names