Media gallery is the standard term for a collection of images and video, used in content management systems, museum software, and institutional websites everywhere. It’s the label on the tab.
That ubiquity is the value. The name fits a digital asset management product, an archive platform, a museum or library collections site, a press image library, or a gallery software tool. The institutional archive reading is the strongest on the .org: museums, universities, and public bodies all maintain media collections and all use that extension.
Digital preservation is worth flagging separately. Institutions hold enormous image and video archives with genuine problems around cataloguing, access, and long-term format survival, and the organisations working on it are nonprofit and academic.
Two common words, no hyphen, exact phrase, and it describes something every institution has and most of them struggle to manage well.
Available now. Offers welcome.