Google has announced the launch of its latest phone in the Pixel series, including support for IPTC Digital Source Type in its industry-leading C2PA implementation.

Many existing C2PA implementations focus on signalling AI-generated content, adding the IPTC Digital Source Type of “Generated by AI” to content that has been created by a trained model.

Google’s implementation in the new Pixel 10 phone differs by adding a Digital Source Type to every image created using the phone, using the “computational capture” Digital Source Type to denote photos taken by the phone’s camera. In addition, images edited using the phone’s AI manipulation tools show the “Edited using Generative AI” value in the Digital Source Type field.

Note that the Digital Source Type information is added using the “C2PA Actions” assertion in the C2PA manifest; unfortunately it is not yet added to the regular IPTC metadata section in the  XMP metadata packet. So it can only be read by C2PA-compatible tools.

Background: what is “Computational Capture”?

The IPTC added Computational Capture as a new term in the Digital Source Type vocabulary in September 2024. It represents a “digital capture” that does involve some extra work using an algorithm, as opposed to simply recording the encoded sample hitting the phone sensor, as with simple digital cameras.

For example, a modern smartphone doesn’t simply take one photo when you press the shutter button. Usually the phone captures several images from the phone sensor using different exposure levels and then an algorithm merges them together to create a visually improved image.

This of course is very different from a photo that was created by AI or even one that was edited by AI at a human’s instruction, so we wanted to be able to capture this use case. Therefore we introduced the term “computational capture”.

For more information and examples, see the Digital Source Type guidance in the IPTC Photo Metadata User Guide.