This Document
This document is a draft. It covers the new Exif version 3.0, only Exif Notes were modified. Modified or added parts of a text are highlighted in yellow, if a headline is highlighted its section was added. |
Copyright
Copyright © 2023 by IPTC, the International Press Telecommunications Council - https://iptc.org. Rights Reserved.
The IPTC Photo Metadata Mapping document is published under the Creative Commons Attribution 4.0 license - see the full license agreement at http://creativecommons.org/licenses/by/4.0/. By obtaining, using and/or copying this document, you (the licensee) agree that you have read, understood, and will comply with the terms and conditions of the license.
This project intends to use materials that are either in the public domain or are available by the permission for their respective copyright holders. All materials of this IPTC standard covered by copyright shall be licensable at no charge.
Acknowledgments
This document is the result of a team effort by members of Photo Metadata Working Group of the International Press Telecommunications Council (IPTC) collaborating with the Exif team of CIPA.
Document Version History
Version | Release Date | Release Status |
---|---|---|
2023.1 |
2022-10-30 |
Exif mapping modified |
2022.1 |
2022-05-17 |
Minor typos fixed |
2022.1 |
2022-02-25 |
Initial version |
About Mapping Photo Metadata
Searching for "mapping metadata" in the web shows thousands of results, the term mapping of digital data is common for a controlled exchange of data values between two or more data models.
In the scope of metadata used for photos, for images, the data models are based on the vocabularies of different photo metadata standards, like IPTC or Exif. Further photo-specific metadata can be mapped to more generic metadata standards, one of them is Schema.org for metadata about a web page and its content.
This document uses the term mapping in this sense:
-
The semantic definitions - the definition of what kind of value this metadata property/tag should hold - of properties/tags of of two or more metadata standards are compared and …
-
… if the semantic definitions are very similar these properties/tags are considered as semantically equivalent: values of these very similar properties/tags can be exchanged across standards.
-
The action of mapping as handing over values from one standard to another one may need following some supportive How-To-rules regarding …
-
Re-formatting of values. E.g. the date and time value formats of standards could be different, but they express the same value.
-
Combining values of multiple properties/tags. E.g. one standard holds data and time values in different properties/tags, another one in a single property/tag. Or one standard provides properties/tags for given name and surname while another standard has only a single property/tag for the name of a person.
-
Single occurrence vs multiple occurrences. One standard defines only a single value can be used for a specific property/tag while another standard allows to use multiple values.
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Mapped Standards
This document is about the mapping between these three metadata vocabularies:
-
IPTC Photo Metadata provides a rich set of metadata with a focus on descriptive data about the image content, rights and licensing related data about the image as asset and administrative data to support a reliable management of the image/asset.
-
Exif Tags provide a rich set of metadata with a focus on data delivered by a camera and with a small set of basic descriptive and rights-related data.
-
The Schema.org vocabulary provides a rich set of metadata properties to support structured data on the web. The metadata is typically integrated into the HTML code of a web page. This vocabulary covers any kind of Creative Work, of course including images.
Be aware for a proper unstanding of Schema.org some knowledge about semantic technology, including W3C’s Resource Description Framework, is required.
How metadata are mapped between these three standards is provided as a guideline in the next chapter.
This document is called a Guideline as we at IPTC have compared semantic definitions and discussed issues with the authorities of the standards and publish agreed findings. But the use of these mappings is not mandatory to fulfill a requirement of a standard, their use is highly suggested.
The Mapping Guidelines
It’s Structure
The Mapping Guidelines chapter has two major sections:
-
The Mappings: For each IPTC property with a suggested mapping to an Exif Tag and/or Schema.org property a table with the formal data for a correct mapping is provided. The structure of the mapping tables is described below.
-
Notes on Mappings: If the formal description of the mapping of a metadata property needs additional free-text guidelines it is provided as Note in this section. The mapping table of the IPTC property includes a hint about this Note with a link to it.
The mapping table (template)
The mapping of an IPTC Photo Metadata property is shown in a generic table format using the following template.
Some rows may be missing, e.g. if no IIM format is defined or no mapping to an Exif tag or
Schema.org property recommended.
Row header | What data is provided by this row |
---|---|
IPTC Name |
The reference name of the IPTC Photo Metadata property defined by its specification. The name is linked to the definition of the property in the IPTC Photo Metadata Standard specification document. |
History Note(s) |
Note(s) about new Exif and/or Schema.org mapping and about modifining a mapping. The note shows this document’s version of change. |
XMP Property |
The identifier of the IPTC Photo Metadata property for the XMP format (Adobe XMP, ISO XMP) as defined by the IPTC Photo Metadata Standard. |
IIM Property |
The identifier and the name of the IPTC Photo Metadata property for the IIM format (IPTC IIM) as defined by the IPTC Photo Metadata Standard. |
Exif Tag |
The Exif Field Name of the tag and its numeric identifer as decimal and hexadecimal value as defined by the Exif specification (Exif). |
Exif Tag Note(s) |
Name(s) of one to many note(s) with a link to its text in the Notes on Mappings section |
Schema.org Property |
Name of the property and its identifier (a URL) linked to the schema.org vocabulary as defined by Schema.org. |
Schema.org Notes |
Name(s) of one to many note(s) with a link to its text in the Notes on Mappings section |
The Mappings
Contributor
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2023.1: Exif new |
XMP Property |
Iptc4xmpExt:Contributor |
Exif Tag |
Special mapping, read Exif notes |
Exif Tag Note(s) |
Copyright Notice
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Exif and Schema.org new |
XMP Property |
dc:rights |
IIM Property |
2:116 Copyright Notice |
Exif Tag |
Copyright, 33432/0x8298 |
Schema.org Property |
copyrightNotice, https://schema.org/copyrightNotice |
Copyright Owner
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
plus:CopyrightOwner |
Schema.org Property |
copyrightHolder, https://schema.org/copyrightHolder |
Creator
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Exif and Schema.org new, 2023.1: Exif changed |
XMP Property |
dc:creator |
IIM Property |
2:80 By-line |
Exif Tag |
Special mapping, read Exif notes |
Exif Tag Note(s) |
|
Schema.org Property |
creator, https://schema.org/creator |
Credit Line
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
photoshop:Credit |
IIM Property |
2:110 Credit |
Schema.org Property |
creditText, https://schema.org/creditText |
CV-Term About Image
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
Iptc4xmpExt:AboutCvTerm |
Schema.org Property |
about, https://schema.org/about |
Schema.org Note(s) |
Date Created
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Exif and Schema.org new |
XMP Property |
photoshop:DateCreated |
IIM Property |
2:55 Date Created+2:60 Time Created |
Exif Tag |
DateTimeOriginal, 36867/0x9003 + SubSecTimeOriginal, 37521/ 0x9291) + OffsetTimeOriginal, 36881/0x9011 |
Exif Tag Note(s) |
|
Schema.org Property |
dateCreated, https://schema.org/dateCreated |
Description
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Exif and Schema.org new |
XMP Property |
dc:description |
IIM Property |
2:120 Caption/Abstract |
Exif Tag |
ImageDescription, 270/0x010E |
Exif Tag Note(s) |
|
Schema.org Property |
caption, https://schema.org/caption |
Description Writer
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
photoshop:CaptionWriter |
IIM Property |
2:122 Writer/Editor |
Schema.org Property |
editor, https://schema.org/editor |
Digital Image GUID
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Exif and Schema.org new |
XMP Property |
Iptc4xmpExt:DigImageGUID |
Exif Tag |
ImageUniqueID, 42016/0xA420 |
Exif Tag Note(s) |
|
Schema.org Property |
identifier, https://schema.org/identifier |
Schema.org Note(s) |
Genre
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
Iptc4xmpExt:Genre |
Schema.org Property |
genre, https://schema.org/genre |
Schema.org Note(s) |
Headline
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
photoshop:Headline |
IIM Property |
2:105 Headline |
Schema.org Property |
headline, https://schema.org/headline |
Image Creator
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Exif new, 2023.1: Exif changed |
XMP Property |
plus:ImageCreator |
Exif Tag |
Mapping in the structure of this IPTC property, read Exif notes |
Exif Tag Note(s) |
Image Rating
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
xmp:Rating |
Schema.org Property |
contentRating, https://schema.org/contentRating |
Image Region
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Exif new |
XMP Property |
Iptc4xmpExt:ImageRegion |
Exif Tag |
SubjectArea, 37396/0x9214 |
Exif Tag Note(s) |
Image Supplier
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
plus:ImageSupplier |
Schema.org Property |
provider, https://schema.org/provider |
Location created
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
Iptc4xmpExt:LocationCreated |
Exif Tag |
Mapping in the structure of this IPTC property, read Exif notes |
Exif Tag Note(s) |
|
Schema.org Property |
locationCreated, https://schema.org/locationCreated |
Location Shown in the Image
Row header | Data |
---|---|
IPTC Name |
|
History Note(s) |
2022.1: Schema.org new |
XMP Property |
Iptc4xmpExt:LocationShown |
Exif Tag |
No mapping, see Exif note |
Exif Tag Note(s) |
|
Schema.org Property |
contentLocation, https://schema.org/contentLocation |
Notes on Mappings
Exif Notes
Exif 3.0 was published in 2023 and required some modifications or additions in the Mapping Guidelines. To clarify which version of the Exif standard is addressed by a note these terms are used:
- Exif 2.3x: all subversions of 2.3 are addressed (2.30, 2.31, 2.32)
- Exif 3.0: version 3.0 is addressed
Exif Note on the data types ASCII and UTF-8
Exif defined the data type "ASCII" in the 1990-ies, this type supports only 7-bit ASCII characters.
This works well for tags holding e.g. DateTime values but causes problems for tags holding free-text values as most non-English languages use characters beyond the ASCII character set. This issue applied to Exif 2.32 and earlier versions and was solved by the Exif 3.0 specification.
Note on Exif 2.32 and earlier versions
For free-text Exif tags only the data type "ASCII" is specified, only 7-bit ASCII code characters may be used.
The approach below still applies when using Exif 2.3x:
In 2008 the Metadata Working Group ([MetadataWG]) issued Guidelines including the advice*) to use UTF-8 as character encoding for such tags when related XMP properties are updated and the tags are synchronized. Since that time this advice has been widely implemented by software used to edit metadata.
This Mapping Guidelines document adopts this advice and clarifies: only ASCII characters or Unicode characters using UTF-8 encoding should be used for the Exif tags like ImageDescription, Coypright or Artist.
*) It is understood that using UTF-8-encoded characters in Exif is formally a violation of the Exif specification permitting only 7-bit ASCII for tags of type ASCII. Therefore some devices (cameras and printers) using the Exif specifications strictly are not able to display non-ASCII characters.
Be aware that the MetadataWG Guidelines were published when Exif 2.21 was the current version.
Note on Exif 3.0:
The data type "ASCII" is specified as in Exif 2.3x covering 7-bit ASCII characters only.
Exif 3.0 introduced “UTF-8” as a new data type covering any Unicode character using the UTF-8 encoding.
Further all free-text Exif tags got "ASCII or UTF-8" as alternative data types, only one of them can be applied and the corresponding data type code must be set.
This allows using most non-English languages for tags like ImageDescription, Coypright, Artist, Photographer, ImageEditor, CameraOwner and others.
Implementers are encouraged to use the alternatives strictly: if the data type "ASCII" is set only 7-bit ASCII characters can be used, if any UTF-8 character beyond ASCII characters is used the data type must be set to "UTF-8".
Exif Note on Contributor
Note on Exif 3.0:
The Exif specification defines the Image Editor tag (42040/0xA438) as “the name of the main person who edited the image”. IPTC has no specific property for this purpose but the more generic property Contributor with the specific role “Image Editor” may be used:
Exif to IPTC mapping
-
If Exif ImageEditor has a value, copy it to IPTC Contributor’s name sub-property and set its role sub-property with the URI of “Content Editor”: https://cv.iptc.org/newscodes/contentprodpartyrole/contentEditor - it is taken from the IPTC NewsCodes vocabulary Content Production Party Role.
IPTC to Exif mapping
-
If an instance of IPTC Contributor has a role sub-property with the URI of “Content Editor” (see above) as value copy the value of the name sub-property to Exif Image Editor only (use the UTF-8 data type) and do not copy it to the Exif Artist tag too.
Exif Note on Copyright Notice
Note on Exif 2.3x:
The Exif specification document notes that the Copyright tag can be used to cover the copyright of the photographer of the image as well as the copyright of an editor of the image.
The use for a copyright for the editor is quite rare; but if you do need to include it be aware that the Exif specification directs you to terminate the string with the photographer copyright with a NULL byte and to concatenate the copyright for the editor following. An alternate solution that does not require a NULL byte is to prefix the copyright claim of the photographer with the string Photographer: and the claim of the editor with the string Editor:.
Be aware that all Exif tag values of type ASCII must have a NULL-byte at the end, read the details in the Exif specification.
Be aware that Exif defines ASCII as the type of this tag, read more about the use of ASCII and UTF-8 above.
Note on Exif 3.0:
The Exif specification changed the semantics of the tag to “It is the copyright notice of the person or organization holding rights to the image” which is much closer to the definition of the IPTC Copyright Notice than the Exif 2.3x definition (see above).
- Exif to IPTC mapping: copy the value of the Exif tag to the IPTC property.
- IPTC to Exif mapping: copy the value of the IPTC property to the Exif tag and use the UTF-8 data type with Exif 3.0.
Be aware that Exif 3.0 defines ASCII or UTF-8 as the data type of this tag.
Exif Note on Creator
Note on Exif 2.3x:
The Exif specification document defines the Artist tag (315/0x013B) as recording "the name of the camera owner, photographer or image creator". For mapping purposes a/ the use of only a single name and b/ the use of only the photographer’s or image creator’s (of e.g. a composite photo) name is recommended.
Be aware that Exif defines ASCII as the type of this tag, read more about the use of ASCII and UTF-8 above.
Note on Exif 3.0:
The Exif 3.0 specification applied a major change to the tag Artist (315/0x013B): the 2.3x specification defined camera owner and/or photographer and/or image creator could be named by this tag. The 3.0 specification defines the Artist tag “records the main person who created the image”.
In addition Exif 3.0 recommends to use the new tags Photographer (42039/0xA437) and Image Editor (42040/0xA438) and the existing Camera Owner tag (42032/0xA430) for persons with a corresponding role. Further the specification defines that Artist “contains the same value of either the CameraOwnerName, Photographer or ImageEditor tag”, this means only a single name.
Regarding the mapping of the Exif tag Image Editor read the Exif Note on Contributor.
Exif defines ASCII or UTF-8 as the data type of all these tags.
Based on the changed Artist specification and the new tags this mapping may be applied:
Exif to IPTC mapping
-
If Exif Photographer has a value: copy the Photographer value to the IPTC Creator.
-
If Exif Photographer has no value and if Exif Artist has a value: copy the Artist value to the IPTC Creator.
-
Mild warning: the specifications of Exif 2.3x and in a limited way of Exif 3.0 allow putting the name of a person who is not the creator (photographer) of the image into the Artist tag. But in practice most of professional imaging software uses this tag only for the creator.
-
IPTC to Exif mapping
-
Copy the value of IPTC Creator to Exif Photographer and Artist tags.
Exif Note on Image Creator
Be aware this Exif Note expects that the values of the IPTC properties Creator and Image Creator/ImageCreatorName are not different. |
Note on Exif 2.3x:
The IPTC property Image Creator uses a structure with the sub-property ImageCreatorName. A mapping of the Exif tag Artist (315,0x13B) to this sub-property may be applied. Read about selecting the photographer’s name from the content of the Artist Tag in the Note on Creator above.
Note on Exif 3.0:
Read about the changed Exif specification of the Artist tag and the introduction of new tags in the Exif Note on Creator above.
The IPTC property Image Creator uses a structure with the sub-property ImageCreatorName.
Based on the changed Artist specification and the new tags this mapping may be applied:
Exif to IPTC mapping
-
If Exif Photographer has a value: copy the value to the ImageCreatorName sub-property of IPTC Image Creator.
-
If Exif Photographer has no value and if Exif Artist has a value: copy the value to the ImageCreatorName sub-property of IPTC Image Creator.
IPTC to Exif mapping
-
Copy the value of the ImageCreatorName sub-property of IPTC Image Creator to the Exif Photographer and Artist tags and use the UTF-8 data type.
Exif Note on Date Created
Be aware that the Exif Tags, the XMP property and the IIM properties use different structures and different formats for the values.
-
Structures: Exif’s DateTimeOriginal holds both date and time, SubSecTimeOriginal the time’s sub-seconds, OffsetTimeOriginal the offset of a local timezone; XMP’s photoshop:DateCreated holds date, time with sub-seconds and timezone offset; IIM’s Date Created holds the date, Time Created holds the time (without sub-seconds) and a timezone offset.
-
Format: Exif’s DateTimeOriginal uses the format
YYYY:MM:DD HH:MM:SS
with time in the 24-hour-format, SubSecTimeOriginal uses as format a sequence of digits, OffsetTimeOriginal format is'+'{or}'-'HH:MM
; the XMP format is the common XML Date-Time plus time zone format likeYYYY-MM-DD’T’hh:mm:ss.sss'+'{or}'-'hh:mm
; IIM’s date format isYYYYMMDD
and the time format ishhmmss'+'{or}'-'hhmm
.
Be aware that Exif and XMP support sub-seconds while IIM does not. Therefore a mapping of a time with sub-seconds from Exif can transfer the full value only to XMP, for IIM the sub-seconds should be ignored. -
IPTC suggests: Read the Exif, the ISO XMP and the IPTC IIM specification for a correct implementation of mapping such values.
Exif Note on Description
The widely used Exif Tag for the description of what an image shows is the Exif ImageDescription.
- Exif to IPTC mapping: copy the value of the Exif tag to the IPTC Description property.
- IPTC to Exif mapping: copy the value of the IPTC Description property to the Exif tag.
Read more about the use of ASCII and UTF-8 data types above.
Exif Note on Digital Image GUID
Note on Exif 2.3x:
The Exif Tag is only set by a camera at the time of capture. The value should only be transferred from the Exif Tag to the IPTC property and not from IPTC to Exif.
The Exif Tag ImageUniqueID is defined as a "unique identifier" of an image and its value is a 128-bit (= 16 bytes) numeric value expressed in the hexadecimal format. This makes a string of 32 characters. If this value is created in a way that guarantees a globally unique value it can be used for the IPTC Digital Image GUID property.
Note on Exif 3.0:
This version of Exif defines the data type of the ImageUniqueID tag as a UUID, version 4 is recommended, compliant with ISO/IEC 9834-8. This fulfills the data type requirements of IPTC’s Digital Image GUID, therefore copy the value of the Exif tag to the IPTC property, this is highly recommended.
Be aware that the Exif specification highly recommends that the value of the Exif tag ImageUniqueID is not changed or deleted during the whole lifetime of the image. Therefore IPTC recommends:
- To copy the UUID from the Exif tag to the IPTC property.
- Not to change the value of the IPTC property.
- If the value of the IPTC property is changed it must not be copied to the Exif tag.
Exif Note on Location Created
If a camera has a built-in GPS receiver or has such a receiver attached one can expect that these tags are set via the GPS data received and this accurately represents the location where the image was created - if so, this perfectly fits a mapping to IPTC’s Location Created.
However, as the values of the GPS Tags can also be set by a geo-location service: where, for example, a photo editor defines a location by names and the service returns GPS data which may be stored in the Exif GPS tags. In this case, the GPS data may not be a good fit for a mapping to Location Created as the used location names refer to a location shown in the image at a distance from the location of the camera. (In such a case the GPS data of such a location does not fit the specification of the Exif GPS tags).
Exif Note on Location Shown in the Image
Exif provides three tags for GPS data about a location: GPSLatitude, GPSLongitude and GPSAltitude. But in most cases - see note above - the values of these tags represent the location of the camera which may be at a considerable distance from the location shown in the image.
Therefore IPTC recommends that you do not map these GPS data to Location Shown.
Exif Note on Image Region
From September 2021 to October 2023 this section had a guideline for mapping data between the IPTC Image Region and the Exif SubjectArea. Unfortunately this mapping was built on the assumption Exif’s SubjectArea may be used for metadata about what this area shows, e.g. the name of a person or an object. This assumption was wrong and therefore the guideline about this mapping was removed in October 2023. Please do not map between the IPTC Image Region and the Exif SubjectArea.
Schema.org Notes
Schema.org Note About How To Use It With Images
The mapping tables show in the Schema.org Property row the name and identifier of a property. As such metadata properties require to be a property of an object this raises the question: of which object defined by Schema.org?
For the use with an image the answer is simple: it must be the Image Object. The web page about this object shows all properties defined for it and all the properties listed in the mapping tables can be found there.
Be aware that the object Image Object is derived from the superior object Creative Work and inherits all its properties.
Schema.org Note on CV-Term About Image
Schema.org defines for superior object Creative Work the property about providing a relationship to "the subject matter of the content". This is the same kind of relationship as from an image to a CV-Term About the Image. The value of about can be any Schema.org Thing, this includes any entity or concept defined by a Controlled Vocabulary(CV)-Term structure of the IPTC standard.
Schema.org Note on Digital Image GUID
IPTC specifies this property as "Globally unique identifier for this digital image". Schema.org has two properties for identifying an Image Object:
-
identifier: It "represents any kind of identifier" and can take a text value as defined for the Digital Image GUID
-
url: It is the URL of the item, but in many cases a URL of a web resource - like an image - is also used as its globally unique identifier.
Consider for mapping from IPTC to Schema.org:
-
If the value of Digital Image GUID is a plain text and not a URL map it only to identifier of a Schema.org Image Object.
-
If the value of Digital Image GUID is a URL you may map it to the identifier and the url of a Schema.org Image Object.
Schema.org Note on Genre
Schema.org defines for the superior object Creative Work the property genre. It takes either a text of a URL.
Consider for mapping from IPTC to Schema.org these alternative options - be aware that IPTC’s Genre uses a CV-Term as structure for the value:
-
You may use the CV-Term Name of the IPTC Genre as genre text value.
-
You may use the CV-Term ID of the IPTC Genre as genre URL value.
Schema.org Note Web on Statement of Rights
IPTC’s Web Statement of Rights is defined as "URL referencing a web resource providing a statement of the copyright ownership and usage rights of the image." If the web resource includes usage rights and as they are very close to the terms expressed by a license IPTC suggests to map the URL of this property to Schema.org’s license property of an Image Object having as specification "A license document that applies to this content".
References
Related standards
Name | Source |
---|---|
Adobe Extensible Metadata Platform (XMP), see https://www.adobe.com/products/xmp/ and https://www.adobe.com/devnet/xmp.html - the specification is published in three parts. |
|
Exchangeable Image file Format (Exif), created and published by the Camera & Imaging Products Assocation CIPA (Japan). Find CIPA documents in English at https://www.cipa.jp/e/std/std-sec.html. Document "CIPA DC-008-Translation 2019 … Exif Version 2.32" is used for the 2.3x mapping, document "CIPA DC-008-Translation 2023 … Exif Version 3.0" is used for the 3.0 mapping. |
|
IPTC Information Interchange Model created and published by IPTC: https://iptc.org/IIM/ and https://iptc.org/std/IIM/4.2/specification/IIMV4.2.pdf |
|
Standard for administrative, descriptive, and copyright information about images created and published by IPTC: overview at https://iptc.org/standards/photo-metadata/iptc-standard/, specifications at https://iptc.org/std/photometadata/specification/IPTC-PhotoMetadata |
|
The XMP Part 1 document is the ISO standard 16684-1. Latest version: Second Edition of 2019-04. |
|
Picture Licensing Universal System created and published by PLUS: find specifications at http://ns.useplus.org |
|
Guidelines of the Metadata Working Group for Handling Image Metadata v 2.0. This document was available at this URL until October 2018: http://www.metadataworkinggroup.com/specs/. Currently the site of this Working Group is not active, but the document can be found at e.g. https://s3.amazonaws.com/software.tagthatphoto.com/docs/mwg_guidance.pdf |
|
Schema.org is a collaborative, community activity behind a vocabulary for structured data on the Internet. See the overview of schemas provided by this community. |
|
W3C Resource Description Framework (RDF), find an overview at https://www.w3.org/RDF/ |