Pictorial indexing is just a specialist type of database indexing covering both still and moving images. Still images in the form of photos or slides are the most commonly indexed, and provide most of the challenges. Moving images are in fact a series of still images with time and (usually) sound components. Moving images in the form of film, video or DVD are usually best approached as catalogue records, and should include a short summary of the action.
Master Indexing can provide either indexing or consultancy services on the indexing of still images. Depending on the subject matter in question, use of a controlled vocabulary, like Australian Pictorial Thesaurus is highly recommended.