Do search engines read image metadata like copyright and author?
Is adding metadata to site's images valuable for SEO?
Photographic metadata (such as EXIF, XMP, and IPTC) contained within images is not used directly by search engines for SEO or otherwise.
In order for it to be used, you would first have to read the metadata using a server-side or desktop application and add it to a webpage so that a search engine could index the information contained within it. This could be added to the image's
alt attribute, title, or caption.
After the metadata is added to the webpage containing the image(s), then it might be helpful towards SEO, depending on what the metadata contains and how this relates to your web page's content and targeted keywords.
For more on this, see: Why Embedded Photo Metadata Won't Help Your SEO (at least without some help)
The main reason to add metadata to a site's images is to aid in protecting them from reuse on other websites. Adding copyright and creator information may help to confirm the source of an image (providing this metadata was not subsequently removed).