Mass Converting .ppm into mp4

[ioletsgo]

I'm wondering if there's a way that I can use the CLI to mass convert a bunch of .ppm flipnote video files into mp4 files, while also retaining the same filename.

[ioletsgo]

Sorry for the very sparsely written issue, I was having a particularly bad headache while I was having this issue.
The main issue is that I have a bunch of .ppm files in a singular directory, and I want to retain the same file name when I convert them
So 0E67D5_0AE14F36BE71F_000.ppm for example will become 0E67D5_0AE14F36BE71F_000.mp4 so it can go down the line and cleanly convert all of the files without any repetition needed on the human front