**Puppet- theatre and cardboard effects**

The puppet-theatre effect is a size distortion characteristic of 3-D images, revealed as an annoying miniaturization that make people and other objects look like animated puppets Spatial distortion prediction system for stereoscopic images.

As a result appears the cardboard effect which is a distortion resulting in an unnatural depth percept, where objects appear distributed in the image as if they were in different discrete depth planes, showing little volume.

Both effects affect to the sensation of reality, spoiling it. The puppet-theatre effect is therefore not perceived as an artifact, physically measurable; rather, but should be subjectively evaluated, as it decreases the quality of the 3D experience.

Studies from the NHK (Japan Broadcasting Corporation) research these phenomena by variation of position of the objects, and shooting, display and viewing conditions to predict the level of distortion introduced by this effect.
