XMP tag

XMP stands for "Extensible Metadata Platform", an XML/RDF-based metadata format which is being pushed by Adobe. Information in this format can be embedded in many different image file types including JPG, JP2, TIFF, GIF, EPS, PDF, PSD, DNG, PNG, DJVU, SVG and MIFF, as well as MOV, AVI, ASF, WMV, FLV, SWF and MP4 videos, and WMA and audio formats supporting ID3v2 information.

The XMP Tag ID's aren't listed because in most cases they are identical to the Tag Name.

All XMP information is stored as character strings. The Writable column specifies the information format: string is an unformatted string, integer is a string of digits (possibly beginning with a '+' or '-'), real is a floating point number, rational is entered as a floating point number but stored as two integer strings separated by a '/' character, date is a date/time string entered in the format "YYYY:MM:DD HH:MM:SS[.SS][+/-HH:MM]", boolean is either "True" or "False", and lang-alt is a list of string alternatives in different languages.

Individual languages for lang-alt tags are accessed by suffixing the tag name with a '-', followed by an RFC 3066 language code (ie. "XMP:Title-fr", or "Rights-en-US"). A lang-alt tag with no language code accesses the "x-default" language, but causes other languages for this tag to be deleted when writing. The "x-default" language code may be specified when writing to preserve other existing languages (ie. "XMP-dc:Description-x-default"), but note that other languages are still deleted if the "x-default" language is deleted. When reading, "x-default" is not specified.

The XMP tags are organized according to schema Namespace in the following tables. Note that a few of the longer namespace prefixes given below have been shortened for convenience (since the family 1 group names are derived from these by adding a leading "XMP-"). In cases where a tag name exists in more than one namespace, less common namespaces are avoided when writing. However, any namespace may be written by specifying a family 1 group name for the tag, ie) XMP-exif:Contrast or XMP-crs:Contrast.

ExifTool will extract XMP information even if it is not listed in these tables. For example, the pdfx namespace doesn't have a predefined set of tag names because it is used to store application-defined PDF information, but this information is extracted by ExifTool.