Patent ID: 8791880
Filing Date: 2014-07-29
Classification: G03B,H04N

Abstract:
1. A pixel position correspondence specifying system, comprising: a projection unit that projects an image on a projection screen; a photographing unit that photographs the image projected on the projection screen; a reference pattern image group generating unit that generates reference pattern image groups each formed from images for each of which a luminance value defined as a function value of a continuous function which continuously changes with changes in phase is determined by varying the phase for each image, the image groups each being an image group having an initial phase value continuously varied on a coordinate-by-coordinate basis along one coordinate axis; a photographing control unit that makes the projection unit project the images belonging to the reference pattern image group, and makes the photographing unit to photograph each image resultingly projected on the projection screen; a phase calculation unit that calculates the initial phase values that correspond to changes in luminance of respective pixels in a plurality of photographic images obtained by the photographing unit by using changes in luminance of pixels in the plurality of photographic images when each image of the reference pattern image group is projected by the projection unit; and an associating unit that conducts an inverse operation of a calculation instituted by the reference pattern image group generating unit upon the initial phase values calculated by the phase calculation unit to derive initial phase values from coordinates, then associates the pixels in the photographic images and the coordinates obtained by the inverse operation, and thus specifies correspondence between pixels in the image to be projected and the pixels in the projection unit, wherein: the reference pattern image group generating unit generates a reference pattern image group concerning a first coordinate axis along which initial phase values are varied, and a reference pattern image group concerning a second coordinate axis along which an initial phase value is changed; the photographing control unit makes the projection unit project the reference pattern image group concerning the first coordinate axis, and makes the photographing unit photograph each image resultingly projected on the projection screen, the photographing control unit further making the projection unit project the reference pattern image group concerning the second coordinate axis, and making the photographing unit photograph each image resultingly projected on the projection screen; the phase calculation unit calculates, from changes in luminance of pixels in a plurality of photographic images obtained by the photographing unit when each image of the reference pattern image group relating to the first coordinate axis is projected by the projection unit, the initial phase values corresponding to the changes in the luminance of the respective pixels in the photographic images, the phase calculation unit further calculating, from changes in luminance of pixels in a plurality of photographic images obtained by the photographing unit when each image of the reference pattern image group relating to the second coordinate axis is projected by the projection unit, the initial phase values corresponding to the changes in the luminance of the respective pixels in the photographic images; and the associating unit calculates coordinates of the first coordinate axis by conducting an inverse operation of a calculation for deriving initial phase values from the coordinates of the first coordinate axis, upon the initial phase values calculated from the photographic images obtained by photographing the reference pattern image group relating to the first coordinate axis, associates the coordinates of the first coordinate axis with the pixels in the photographic images, next after calculating coordinates of the second coordinate axis by conducting an inverse operation of a calculation for deriving initial phase values from the coordinates of the second coordinate axis, upon the initial phase values calculated from the photographic images obtained by photographing the reference pattern image group relating to the second coordinate axis, associates the coordinates of the second coordinate axis with the pixels in the photographic images, the associating unit thus specifying correspondence between the pixels of each photographic image and those of each image to be projected by the projection unit, and using the correspondence between the pixels and coordinates of the photographic image to specify the correspondence between the pixels in the image to be projected and the pixels in the projection unit.