Indesign CC Libriaries - placed image grouping?

Hi there! I have a number of images placed throughout a very large document in indesign. I have used CC libraries to place them all. It seems like it would be fairly easy to automatically create a group or sort my library based on the images I have already placed. However I can't seem to find a way to do that. Yes -  in hindsight, I should have created a group and added the images as I went. Lesson learned. Aside from using my links panel and going through one by one and manually creating a group in the library's panel, am I missing something? Is there a way to automate this? Thank you!!