[Persona 4 Dancing All Night] Need help with decoding .usm movies to .mp4

[RedoOfDemifiend]

Hey everyone!

I've been struggling for about a week by now to find a way to convert movies (.usm) from Persona 4 Dancing (PSVita) to any video format. What i am specifically looking for is video-backdrops that occasionally play during dances. i wasn't able to find them separately so i have to convert them myself.

I rtied all the tools listed on the wiki page with no success. It seems that all of them would be able to convert movies from mainline games, but not something as niche as a dancing game.

Is there any way to convert them?

[ShrineFox]

I think those tools should still work for the Dancing games, so I wonder if the files you extracted from the Vita are still encrypted? Getting them from the game's ux0:app folder, that's usually the case. If you select the folder in Vitashell and press (I think) Triangle to open the menu and choose "Open Decrypted", you should be able to then transfer the files to PC without the encryption. A quick way to tell would be to open them in a hex editor and see if the data looks completely random with no discernable pattern to it.
The start of a valid USM file should look something like this:

[RedoOfDemifiend]

I think those tools should still work for the Dancing games, so I wonder if the files you extracted from the Vita are still encrypted? Getting them from the game's ux0:app folder, that's usually the case. If you select the folder in Vitashell and press (I think) Triangle to open the menu and choose "Open Decrypted", you should be able to then transfer the files to PC without the encryption. A quick way to tell would be to open them in a hex editor and see if the data looks completely random with no discernable pattern to it.
The start of a valid USM file should look something like this:

Seems to be identical to what i see

I tried both physical and Vita3K files, same result. Can you tell which program exactly to use?