I don't remember everything about it, but I remember most of the video as if I saw it yesterday. Sadly I don't think it will help since I don't know the genre. So, I'm sorry.
It was in a kind of animated style. The characters looked like cardboard, and it starts by a young woman in a trial surrounded by tall people, until they decide that the punishment would be sending her to a giant castle in a snow globe in the mountains, where she would be until her death.
She is forced into a capsule and sent away. While she is away, she trains doves to go outside and make some forms. Hearts, or even words like "peace" and others.
The video cuts to a guy in an adventure, walking through forests and trying to get to the "castle". Anyway, it cuts to the woman again, seeing her doves getting killed and being less and less doves everyday.
I don't actually remember what happens next, but the guy is able to get to the castle, but when he arrives the woman is already dead.
If you are able to find the video just by this, I'm going to be impressed. I'm going to keep looking and trying to find it on my own meanwhile.