Should I be using jquery or vanilla javascript to write code for client side image upload security

I am in the process of creating a rock solid secure image upload system for a website I am working on.

Naturally, I want to do client side checks to validate the image file (jpg or png), before I upload it for further checks to the server (using php) - and I assume for that I will use Javascript.

I know there is quite a lot to take into consideration here, so I'm taking it one step at a time.

My question is this, SHOULD I be using jquery for the client side image verification or vanilla javascript.

I know jquery is just javascript ultimately, but I have a propensity to do this with vanilla javascript. Personally I think vanilla javascript 'reads' better as code than jquery. I would also assume it's actually faster at execution.

Online, there is almost no useful information about vanilla javascript with regards to secure image file validation (there are snippets here and there I know) - but there is lots of information about jquery. I am the sort of person who likes to do things 'raw'. So that I can understand fully what my code is doing without any wrapper.

Am I missing something? Is jquery really great at something I'm not understanding? I see jquery code, and the equivalent javascript code, and don't really understand why people are so 'into' jquery. The code lengths are generally similar, and am personally not afraid of coding a bit more if that's what it takes.

I think part of it might be that jquery is all over the internet, and vanilla javascript isn't, so grabbing code that 'works' is easier, but I'm just wondering if I'm missing the point entirely.