windows - Batch file to delete all but largest file in a directory

I have a very large directory of files, each with it'd own subdirectory. In those subdirectories are videos of various qualities (1080p, 720p... etc). I only want to keep the video of the highest quality (therefore the largest size). Is there a way to do this via command-line or batch file?

Parent_directory


- Video_A
-- Video_A_1080p
--video_A_720p

-Video_B
-- Video_B_1080p
--video_B_720p
-- Video_B_480p

Note that the name of the videos do not necessarily have the resolutions in the file name. I'm just illustrating the directory structure.

The result should be:

Parent_directory

- Video_A
-- Video_A_1080p


-Video_B
-- Video_B_1080p