The background looks just like the living room CG from the game.
Can't tell if the artist redrew it or blew it up, though.

I'm fairly sure it was upscaled for this; you wouldn't painstakingly redraw a background like that only to put a blur filter on top so that it has even less detail than the original, unless you were silly in the head.

Also, nice catch. It's been so long since I read Tsukihime that I forgot what that background looked like.

I kinda figured, and now that I look at it further, even the details in the photo on the wall match the game CG. I'll tag it with photo_background then. Thanks.

But you're totally right, it would be nuts to meticulously recreate even the pattern on the sofa just to make it blurry at the end.