Yes, although quite a solid-looking thwhack. My grammar school headmaster never gave less than 3, but if he'd ever been restricted to 1 stroke I don't think he would have been ashamed of this one, from a purely technical point of view.
If you download it and view it frame by frame, you can see that the lad is holding his arse even as he turns to walk away from the chair, and is still holding it when he is summoned back to pick up the thing he's dropped on the floor; which suggests the punishment had some impact.
The deal with the .. actually I think it's a file or a magazine: most Singapore schools seem to do this. It's odd - I haven't come across it anywhere else in a school CP context, but the idea is to slot something into the boy's trouser waistband at the rear to protect his lower spine if the cane stroke should go too high.
See e.g. the same kind of thing in this play-acting version from St Gabriels (one of several boys-only Catholic schools celebrated for canings in SG) -- not the real thing, of course, but illustrative of the technique:
And in this one from Ahmad Ibrahim Secondary, again boys acting out caning, you can see that the boy has a book in his pants just above his butt:
Personally, I'd have thought all this was unnecessary as long as the culprit is bending over far enough. In the real-life example, he arguably isn't (hands on chair seat; for a boy this big, it ought to be elbows on seat.)
No such precautions are illustrated in this play-acting version from Clementi Town Secondary:
Good example of how the bending-over ought to be done (in my humble opinion), elbows on a low table, feet somewhat apart, arse up a bit and out a bit, in this fictional version from "I Not Stupid Too", this year's Singaporean movie hit - filmed at Presbyterian High, where in real life they quite frequently do do public canings in this very hall: