Script to delete files that don't match certain filenames

I have a folder with 500,000 images, sorted in subfolders by year and month. I'd like to create a script that does this:

if filename does not match any of the filenames in names.log then delete the file

names.log would contain filenames, like:

image1.jpg

photo3.jpg

redcar.jpg

balloon2323.jpg

etc... it has about 10,000 names of files I want to KEEP

I have PHP and Python on the server but I'm not sure what would be best for this. I haven't done any scripting before. Could anyone be so kind as to give me a snippet of code that would achieve that and let me know how to run it? Or maybe this can be achieved with a command instead?

Thank you!