I use PixivUtil2 to batch download art, and I had fucked with the naming config of downloaded files. Most of the art I have is saved like this "xxxxxxxx - xxxxxx_p0" With the first x's being the #'s corresponding to the user ID of the artist, and the group being the actual image ID. I want only the image ID (xxxxxxx_p0) so that the pixiv search option shows up with 4chanX for other posters. I've already changed this for PixivUtil2 in the config, but I have thousands of images I've already sorted that I need to rename.
The issue is that the number of digits in the user ID and Image ID is variable and I'm having trouble figuring out how to rename all of them with a bulk renaming program while preserving the format I want.