The Cover Image feature allows you to use the image for one item as the representative image for another item. You typically specify a Cover Image only for items of type Article. An article usually has no image attached to it because an article’s content is text. When an article does have an attachment, the attached file is usually a PDF document. In that case, Omeka will display an image of the text on the PDF’s first page as shown here. The Cover Image feature allows you to associate a photograph or other image with an Article without attaching the image file to the Article’s item.
Cover Images address the fact that an Article generally provides lifelong information about something, like biographical information for a person, or the history of a house, whereas a photograph literally captures a moment in time. Over its lifetime, a person or building may have been photographed many times. Each photograph belongs to its own Image item having metadata describing what’s known about the image, such as when it was taken, where, and by whom. If you were to attach an image to an Article’s item, there would be no place to store the image’s metadata because the article already contains metadata for that item. Thus each article and image needs its own item.
Despite the need to separate articles from images, it’s desirable to associate an image with an Article so that when you view the Article, a picture of the subject is prominently displayed. This is where Cover Images come in. In the screenshot below, the portrait in the upper left is the Cover Image for Article 13579, but the image itself is attached to item 11562.
The Archive Relational Model allows the lifelong information in an Article to coexist with the fleeting instance of a photograph by allowing each Image item to have a depicts relationships to an Article, and conversely, allowing each Article item to be depicted by one or more Image items. The screenshot above shows Article item 13579 for a women named Annie Downs Clark for whom the Archive contains several images, but only a small amount of biographical information. The portrait of Annie as a young girl that appears in the upper left, comes from Image item 11562 and serves as the Cover Image for item 13579. The metadata for 11562, tells us that the portrait was taken by John C. Ralph around 1899 which would make Annie about 11 years old the day she posed for this picture.
Setting a Cover Image
You set the Cover Image for an item by editing the item and choosing the Cover Image tab which appears when the AvantRelationships plugin is installed. To specify or change the item’s Cover Image, enter the Identifier number of the item containing the desired image, and then click the Save Changes button.