Explainable Search and Discovery of Visual Cultural Heritage Collections with Multimodal Large Language Models

Many cultural institutions have made large digitized visual collections available online, often under permissible re-use licences. Creating interfaces for exploring and searching these collections is difficult, particularly in the absence of granular metadata. In this paper, we introduce a method for using state-of-the-art multimodal large language models (LLMs) to enable an open-ended, explainable search and discovery interface for visual collections. We show how our approach can create novel clustering and recommendation systems that avoid common pitfalls of methods based directly on visual embeddings. Of particular interest is the ability to offer concrete textual explanations of each recommendation without the need to preselect the features of interest. Together, these features can create a digital interface that is more open-ended and flexible while also being better suited to addressing privacy and ethical concerns. Through a case study using a collection of documentary photographs, we provide several metrics showing the efficacy and possibilities of our approach.