Media files - removing unused images

[vis18neu]

We need to clear all unused images left from older VM versions. Our VM version is 2.0.26d. We found the advice that the best way to do so is to export mySQL table for media files and compare it with the images/stories/virtuemart/product and images/stories/virtuemart/category folders, but we cannot find the description of media table/files - What image files are recorded in that table/admin option in VM: published and unpublished images, only published images, only main product images, all product images (main and additional), all product and category images... Could someone clarify this? Thanks.