We at IPTC receive many requests for help and advice regarding editing embedded photo and video metadata, and this has only increased with the recent news about the IPTC Digital Source Type property being used to identify content created by a generative AI engine.

In response, we have created some guidance: Developers’ and power users’ guide to reading and writing IPTC Photo Metadata 

This takes the form of a wiki, so that it can be easily maintained and extended with more information and examples.

In its initial form, the documentation focuses on:

• Using the ExifTool command-line tool to read and write IPTC Photo Metadata,. ExifTool is commonly used by developers and power users to explore embedded metadata;
• Reading and writing image metadata in Python using the pyexiftool module;
• Reading and writing metadata in JavaScript (or TypeScript) using the node-exiftool module.

In each guide, we advise on how to read and create DigitalSourceType metadata for generative AI images, and also how to read and write the Creator, Credit Line, Web Statement of Rights and Licensor information that is currently used by Google image search to expose copyright information alongside search results.

We hope that these guides will help to demystify image metadata and encourage more developers to include more metadata in their image editing and publishing workflows.

We will add more guidance over the coming months in more programming languages, libraries and frameworks. Of particular interest are guides to reading and writing IPTC Photo Metadata in PHP, C and Rust.

Contributions and feedback are welcome. Please contact us if you are interested in contributing.

The IPTC is proud to announce that after intense work by most of its Working Groups, we have published version 1.0 of our guidelines document: Expressing Trust and Credibility Information in IPTC Standards.

The culmination of a large amount of work over the past several years across many of IPTC’s Working Groups, the document represents a guide for news providers as to how to express signals of trust known as “Trust Indicators” into their content.

Trust Indicators are ways that news organisations can signal to their readers and viewers that they should be considered as trustworthy publishers of news content. For example, one Trust Indicator is a news outlet’s corrections policy. If the news outlet provides (and follows) a clear guideline regarding when and how it updates its news content.

The IPTC guideline does not define these trust indicators: they were taken from existing work by other groups, mainly the Journalism Trust Initiative (an initiative from Reporters Sans Frontières / Reporters Without Borders) and The Trust Project (a non-profit founded by Sally Lehrman of UC Santa Cruz).

The first part of the guideline document shows how trust indicators created by these standards can be embedded into IPTC-formatted news content, using IPTC’s NewsML-G2 and ninjs standards which are both widely used for storing and distributing news content.

The second part of the IPTC guidelines document describes how cryptographically verifiable metadata can be added to media content. This metadata may express trust indicators but also more traditional metadata such as copyright, licensing, description and accessibility information. This can be achieved using the C2PA specification, which implements the requirements of the news industry via Project Origin and of the wider creative industry via the Content Authenticity Initiative. The IPTC guidelines show how both IPTC Photo Metadata and IPTC Video Metadata Hub metadata can be included in a cryptographically signed “assertion” 

We expect these guidelines to evolve as trust and credibility standards and specifications change, particularly in light of recent developments in signalling content created by generative AI engines. We welcome feedback and will be happy to make changes and clarifications based on recommendations.

The IPTC sends its thanks to all IPTC Working Groups that were involved in creating the guidelines, and to all organisations who created the trust indicators and the frameworks upon which this work is based.

Feedback can be shared using the IPTC Contact Us form.

The IPTC NewsCodes Working Group has approved an addition to the Digital Source Type NewsCodes vocabulary.

The new term, “Composite with Trained Algorithmic Media“, is intended to handle situations where the “synthetic composite” term is not specific enough, for example a composite that is specifically made using an AI engine’s “inpainting” or “outpainting” operations.

The full Digital Source Type vocabulary can be accessed from https://cv.iptc.org/newscodes/digitalsourcetype. It can be downloaded in NewsML-G2 (XML), SKOS (RDF/XML, Turtle or JSON-LD) to be integrated into content management and digital asset management systems.

The new term can be used immediately with any tool or standard that supports IPTC’s Digital Source Type vocabulary, including the C2PA specification, the IPTC Photo Metadata Standard and IPTC Video Metadata Hub.

Information on the new term will soon be added to IPTC’s Guidance on using Digital Source Type in the IPTC Photo Metadata User Guide.

CIPA, the Camera and Imaging Products Association based in Japan, has released version 3.0 of the Exif standard for camera data.

The new specification, “CIPA DC-008-Translation-2023 Exchangeable image file format for digital still cameras: Exif Version 3.0” can be downloaded from https://www.cipa.jp/std/documents/download_e.html?DC-008-Translation-2023-E.

Version 1.0 of Exif was released in 1995. The previous revision, 2.32, was released in 2019. The new version introduces some major changes so the creators felt it was necessary to increment the major version number.

Fully internationalised text tags

In previous versions, text-based fields such as Copyright and Artist were required to be in ASCII format, meaning that it was impossible to express many non-English words in Exif tags. (In practice, many software packages simply ignored this advice and used other character sets anyway, violating the specification.)

In Exif 3.0, a new datatype “UTF-8” is introduced, meaning that the same field can now support internationalised character sets, from Chinese to Arabic and Persian.

Unique IDs

The definition of the ImageUniqueID tag has been updated to more clearly specify what type of ID can be used, when it should be updated (never!), and to suggest an algorithm:

This tag indicates an identifier assigned uniquely to each image. It shall be recorded as an ASCII string in hexadecimal notation equivalent to 128-bit fixed length UUID compliant with ISO/IEC 9834-8. The UUID shall be UUID Version 1 or Version 4, and UUID Version 4 is recommended. This ID shall be assigned at the time of shooting image, and the recorded ID shall not be updated or erased by any subsequent editing.

Guidance on when and how tag values can be modified or removed

Exif 3.0 adds a new appendix, Annex H, “Guidelines for Handling Tag Information in Post-processing by Application Software”, which groups metadata into categories such as “structure-related metadata” and “shooting condition-related metadata”. It also classifies metadata in groups based on when they should be modified or deleted, if ever.

Collaboration between CIPA and IPTC

CIPA and IPTC representatives meet regularly to discuss issues that are relevant to both organisations. During these meetings IPTC has contributed suggestions to the Exif project, particularly around internationalised fields and unique IDs.

We are very happy for our friends at CIPA for reaching this milestone, and hope to continue collaborating in the future.

Developers of photo management software understand that values of Exif tags and IPTC Photo Metadata properties with a similar purpose should be synchronised, but sometimes it wasn’t clear exactly which properties should be aligned. IPTC and CIPA collaborated to create a Mapping Guideline to help software developers implement it properly. Most professional photo software now supports these mappings.

Complete list of changes in Exif 3.0

The full set of changes in Exif 3.0 are as follows (taken from the history section of the PDF document):

• Added Tag Type of UTF-8 as Exif specific tag type.
  • Enabled to select UTF-8 character string in existing ASCII-type tags
• Enabled APP11 Marker Segment to store a Box-structured data compliant with the JPEG System standard
• Added definition of Box-structured Annotation Data
• Added and changed the following tags:
  • Added Title Tag
  • Added Photographer Information related Tags (Photographer and ImageEditor)
  • Added Software Information related Tags (CameraFirmware, RAWDevelopingSoftware, ImageEditingSoftware, and MetadataEditingSoftware)
  • Changed Software, Artist, and ImageUniqueID
  • Corrected incorrect definition of GPSAltitudeRef
  • GPSMeasureMode tag became to support positioning information obtained from GNSS in addition to GPS
• Changed the description support levels of the following tags:
  • XResolution
  • YResolution
  • ResolutionUnit
  • FlashpixVersion
• Discarded Annex E.3 to specify Application Software Guidelines
• Added Annex H. (at the time of publication) to specify Guidelines for Handling Tag Information in Post-processing by Application Software
• Added Annex I.and J. (both at the time of publication) for supplemental information of Annotation Data
• Added Annex K. (at the time of publication) to specify Original Preservation Image
• Corrected errors, typos and omissions accumulated up to this edition
• Restructured and revised the entire document structure and style

At today’s Google I/O event keynote, Sundar Pichai, CEO of Google, explained how Google will be using embedded IPTC image metadata to signal visual media created by generative AI models.

“Moving forward, we are building our models to include watermarking and other techniques from the start,” Pichai said. “If you look at a synthetic image, it’s impressive how real it looks, so you can imagine how important this is going to be in the future.

“Metadata allows content creators to associate additional context with original files, giving you more information whenever you encounter an image. We’ll ensure every one of our AI-generated images has that metadata.”

The IPTC Photo Metadata section of Google Images’ guidance on metadata has been updated with new guidance on the DigitalSourceType field:

This follows the guidance on IPTC Photo Metadata for Generative AI that was recently published by IPTC.

“AI-Generated” label on Google Images

The above guidance hints at an “AI-generated label” to be used on Google Images in the future. Google recommends that all creators of AI-generated images use the IPTC Digital Source Type property to signal AI-generated content. While Google says that “you may not see the label in Google Images right away”, it appears that it will soon be available in Google Images search results.

The IPTC has updated its Photo Metadata User Guide to include some best practice guidelines for how to use embedded metadata to signal “synthetic media” content that was created by generative AI systems.

After our work in 2022 and the draft vocabulary to support synthetic media, the IPTC NewsCodes Working Group, Video Metadata Working Group and Photo Metadata Working Group worked together with several experts and organisations to come up with a definitive list of “digital source types” that includes various types of machine-generated content, or hybrid human and machine-generated media.

Since publishing the vocabulary, the work has been picked up by the Coalition for Content Provenance and Authenticity (C2PA) via the use of digitalSourceType in Actions and in the IPTC Photo and Video Metadata assertion. But the primary use case is for adding metadata to image and video files

Here is a direct link to the new section on Guidance for using Digital Source Type, including examples for how the various terms can be used to describe media created in different formats – audio, video, images and even text.

IPTC recommends that software creating images using trained AI algorithms uses the “Digital Source Type” value of “trainedAlgorithmicMedia” is added to the XMP data packet in generated image and video files. Alternatively, it may be included in a C2PA manifest as described in the IPTC assertion documentation in the C2PA specification.

The official URL for the full vocabulary is http://cv.iptc.org/newscodes/digitalsourcetype, so the complete URI for the recommended Trained Algorithmic Media term is http://cv.iptc.org/newscodes/digitalsourcetype/trainedAlgorithmicMedia.

Other terms in the vocabulary include:

• Composite with synthetic elements – https://cv.iptc.org/newscodes/digitalsourcetype/compositeSynthetic – covering a composite image that contains some synthetic and some elements captured with a camera;
• Digital Art – https://cv.iptc.org/newscodes/digitalsourcetype/digitalArt – covering art created by a human using digital tools such as a mouse or digital pencil, or computer-generated imagery (CGI) video
• Virtual recording – https://cv.iptc.org/newscodes/digitalsourcetype/virtualRecording – a recording of a virtual event which may or may not contain synthetic elements, such as a Fortnite game or a Zoom meeting
• and several other options – see the full list with examples in the IPTC Photo Metadata User Guide.

Of course, the original digital source type values covering photographs taken on a digital camera or phone (digitalCapture), scan from negative (negativeFilm),  and images digitised from print (print) are also valid and may continue to be used. We have, however, retired the generic term “softwareImage” which is now deemed to be too generic. We recommend using one of the newer terms in its place.

If you are considering implementing this guidance in AI image generation software, we would love to hear about it so we can offer advice and tell others. Please contact us using the IPTC contact form.

Our friends at CEPIC are running a webinar in conjunction with Google on the Licensable badge in search results. The webinar is TODAY, February 21st, so there are still a few hours left to join.

Register for free at https://www.eventbrite.com/e/google-webinar-image-seo-and-licensable-badge-tickets-532031278877

Google webinar: Image SEO and Licensable Badge

In this webinar, John Mueller, Google’s Search Advocate, will cover Image SEO Best Practices and Google’s Licensable Badge. For the Licensable Badge, John will give an overview of the product and implementation guidelines. There will also be time for a Q&A session.

One of the methods for enabling your licensing metadata to be surfaced in Google Search results is to embed the correct IPTC Photo Metadata directly into image files. The other is to use schema.org markup in the page hosting the image. We explain more in the Quick Guide to IPTC Photo Metadata on Google Images, but you can also learn about it by attending this webinar.

Tuesday 21st February 2023, at 4 PM – 5PM Central European Time

Topics covered include:

• Image SEO best practices

• Licensable badge in Google image search results

• Q&A

This is a free webinar open to all those interested, not just CEPIC or IPTC members.

We had a great Photo Metadata Conference last Thursday. Thanks to those who attended. For those who didn’t, or those who would like to go over some detail again, here we publish full recordings of all sessions.

First up, Brendan Quinn, IPTC Managing Director introduced the day and gave an overview of what was to come:

Next was a great panel on adoption of the accessibility properties added in the 2021.1 update to the IPTC Photo Metadata Standard. We are very happy to share that the fields are now supported in many popular photo creating and editing tools, with more to come:

Next was David Riecks and Michael Steidl, co-leads of the IPTC Photo Metadata Working Group, presenting the work done by the Working Group since the last Photo Metadata Conference:

Then came a session on real-world implementations of the C2PA specification for content authenticity, including presentations from Microsoft, CBC / Radio Canada, the BBC and Adobe / Content Authenticity Initiative:

The last session was a panel discussion on Metadata for AI Images, looking at questions around the ethics of using copyrighted content to train a machine learning engine to generate AI images, and how the IPTC Photo Metadata Standard could be extended to support metadata appropriate for AI-generated images:

We had a great session and a packed conference! We look forward to seeing everyone again at next year’s event.

Today, the IPTC announces the release of the IPTC Photo Metadata Standard, version 2022.1.

The update has some changes to align the IPTC Photo Metadata Standard more closely which IPTC Video Metadata Hub, which helps with the integration into the C2PA specification as announced earlier this week.

The changes will be presented today (Thursday 10 November) at the IPTC Photo Metadata Conference, alongside sessions on AI and images, C2PA, and accessibility. You can still register for today’s Photo Metadata Conference, for free, at the IPTC Photo Metadata Conference 2022 event page. Video recordings from the event will be posted in the coming weeks.

The changes in detail

The IPTC Core schema has been updated to version 1.4, including the following changes:

• New property Contributor (matching the equivalent property in IPTC Video Metadata Hub)

• The property structure for Product has been extended with a new property Identifier

The specification document has also been updated with some edits and additions to Help Texts and User Notes.

Technical Reference update

The IPTC Photo Metadata TechReference has also been updated to include the changes in version 2022.1. This can be used by software makers to easily include the changes in the new version.

For more information on how to use the Technical Reference, please consult the IPTC Photo Metadata Technical Reference documentation.

Questions? Comments?

For any questions or comments on this update or on the IPTC Photo Metadata Standard in general, please post to the public IPTC Photo Metadata forum at iptc-photometadata@groups.io.

We are happy to announce that IPTC’s work with C2PA, the Coalition for Content Provenance and Authority, continues to bear fruit. The latest development is that C2PA assertions can now include properties from both the IPTC Photo Metadata Standard and our video metadata standard, IPTC Video Metadata Hub.

Version 1.2 of the C2PA Specification describes how metadata from either the photo or video standard can be added, using the XMP tag for each field in the JSON-LD markup for the assertion.

For IPTC Photo Metadata properties, the XMP tag name to be used is shown in the “XMP specs” row in the table describing each property in the Photo Metadata Standard specification. For Video Metadata Hub, the XMP tag can be found in the Video Metadata Hub properties table under the “XMP property” column.

We also show in the example assertion how the new accessibility properties can be added using the Alt Text (Accessibility) field which is available in Photo Metadata Standard and will soon be available in a new version of Video Metadata Hub.