Projection apparatus, projection method and projection program medium that determine a roll angle at which the projection apparatus is to be turned to correct a projected image to be a rectangular image on a projection target

摘要

A CPU controls an attitude adjustment unit to change the lengths of legs of an electric leg part independently of each other so that a roll angle is changed to roll a projected image, and controls an image converter to correct the projected image to be a rectangular image on a projection target based on the changed roll angle.

主权项

1. A projection apparatus comprising:
a roll angle determination unit configured to determine a roll angle at which the projection apparatus is to be turned; a roll angle changing unit configured to turn the projection apparatus at the determined roll angle; a distortion correction unit configured to correct a projected image to be a rectangular image on a projection target based on the determined roll angle; and an obtaining unit configured to obtain relative angles between the projection apparatus and the projection target; wherein the roll angle determination unit determines the roll angle based on the obtained relative angles; and wherein when a horizontal angle and a vertical angle of the relative angles are represented by h and v, respectively, and the roll angle is represented by r, the roll angle determination unit determines the roll angle r by using:p=arcsin⁡(sin⁢⁢h⁢⁢cos⁢⁢v)q=arcsin⁢⁢sin⁢⁢vcos⁢⁢pr=sgn⁢⁢hv⁢⁢arccos⁢⁢cos⁢⁢qcos⁢⁢vwheresgn⁢⁢x={1⁢:⁢x>00⁢:⁢x=0-1⁢:⁢x<0.