Artists can foreshorten and angle linear perspective to deform and change the scale of an object. The image becomes incomprehensible when viewed directly but resolves into a clear picture when looked at from a different vantage point.
There are two types of anamorphosis: optical, also known as direct or oblique; and catoptric.
Optical anamorphosis requires the viewer to look at a picture from an unusual angle instead of standing in front of the painting and looking at it straight on.
Catoptric anamorphosis requires the image to be seen reflected in a conical, cylindrical or pyramidal mirror.
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