How to share a video and apply a watermark?

Question

Video

Hello . The question is, there are films that I want to divide into two parts and put a watermark on each part. But I tried to do this through the Video Editing program, as a result, she made films 1280 wide and 1920 high. Please tell me any program in which you can do this without losing quality so that the dimensions of the movie are the same. Thank you in advance .
PS Or if available, please provide a link to articles or video tutorials.

Answer 1

Avidemux is great for this.

Answer 2

You can cut without quality loss using Boilsoft video splitter

Answer 3

To do this without losing quality, you need the original format to allow it.
If you already have a fully assembled and already reaped material, then
without loss of quality it will no longer work. Basically it won't work.
If you need to put the work of drawing a character onto a stream, then specialized command line utilities will help you.
In addition to the convenience of mass processing of a large number of files, they also conveniently control the loss of quality.
AviSynth - IMHO, the best of them.
But I don't get it:
Why would you want to maintain perfect quality when you're going to put a huge watermark on the picture anyway? From the point of view of human perception, the quality will still fall. Why try to keep a crystal clear picture outside of the watermark? The human eye still does not appreciate it.