Google reads IPTC photo metadata embedded in image files and can display credit, creator and licensing information alongside an image in results.
Licensable images
Add ImageObject structured data with license and acquireLicensePage, or the equivalent IPTC fields, and Google can show a “Licensable” badge with a link to your licensing page.
Preserving metadata
Many image pipelines strip metadata during optimisation. If credit matters to you, verify it survives your build, check the delivered file, not the original.
Alien Road recommends: check whether your optimiser strips IPTC data before you invest in adding it. We have seen photographers add full licensing metadata that the site build silently removed on every deploy, weeks of work that never reached a single visitor.