Blanc et Noir (French for "White and Black") was the sole Death Note Artbook illustrated by Takeshi Obata. It was never released outside of Japan. Aside from Death Note art, the book contains various other works by Obata that have nothing to do with the series.
Takeshi Obata's art style is a bit different from typical manga art. His characters are realistic looking, as well as background, a lot of detail goes into them. His colouring is painting like which sets it apart from other manga artists.