How to upscale and post process a video file?
 

I recently downloaded some videos of a tv series.
The person that I got them from had "Upscaled and Post processed" written in the title.
On the site I got them from, the person said they did this.
It is now a really good picture quality.
I have some series I would like to be able to do this to, but I don't know how or exactly which program to use.
Can anyone help me?
I would really appreciate it.
Thank you

I'd have to see a sample of this.

Too many people are just full of BS when it comes to video processing. Others actually butcher the video, and don't truly improve it. And anytime upscaling is done, it opens a can of worms.