Explanation time! :-D
Tobiano - Color on the flank and chest is an obvious giveaway. The color on his face is probably caused by tobiano too, because it does not put color on the face, where as splash, sabino, and frame do. It's interesting to see patterns conflict each other.
Splash - The amount of white on the lower half of his face and how white his legs are. Tobiano likes to have color down to the knees/hocks.
Frame - The amount of white on the top half of his face and the way it spreads horizontally. Though neither of these pictures show both sides of his head. All of his face white could
be caused by just splash, but splash, frame, and sabino like to work together in combinations more often than not.
Sabino - The edges of his spots look slightly jagged, but the eyeliner he has is what makes me think sabino. Sabino likes to keep color around the eyes.
It becomes much easier when you learn what each pattern does and start looking at multiple patterns as layers on top of each other.