Possible to map multiple records to same library asset via image field?

I have an application in which I upload image files to the Drupal server via an external process, and then use media_feeds to create media library assets based on matching image names in imported records and assign them to images fields in the resulting Drupal nodes. Each imported record may have multiple image names that require mapping, so the target image field is multi-valued. I found that I can do this by using URI as the target mapping for the image field, and it works fine. However, imported records often contain the same image name and thus ideally should use the same media asset - the first record should create it, and subsequent records should simply map to it. Unfortunately, I instead see a (renamed) copy of the image added to the library for each imported reference to it. Is it possible to avoid this duplication?