Ambiguous Garage Roof
Kokichi Sugihara from Meiji University in Japan created this video of an ambiguous garage roof which completely changes in appearance when its reflection is viewed in a mirror. Viewed one way, the roof appears to be round while it seems to be corrugated when viewed from the opposite angle. The actual shape is neither round nor corrugated. According to Sugihara:
This illusory solid was discovered by combining two observations. One is a mathematical observation that a single image does not covey depth information, and the other is a psychological observation that the human brains like right angles in interpreting an image. Indeed we are apt to interpret the edge curve of the roof as an intersection of a roof with a plane perpendicular to the axis of the roof.
This optical illusion is a finalist for the 2015 Best Illusion of the Year Contest. What do you think about it?