how can i retrieve SamsungGalaxy S4 camera folder?

[AC Question]

I thought I was deleting a single video, but my entire camera folder is gone, no longer visible when checked on a pc.

 

[Rukbat]

The phone has to be rooted to retrieve deleted files. (That's due to the way Linux is built, it has nothing to do with Android.)

Try DiskDigger undelete (root) - the free version will undelete pictures (jpgs), but for anything else, you have to pay for it.