Patent ID: 7596286
Filing Date: 2009-09-29
Classification: G06T

Abstract:
1. An image processing apparatus for correcting distortion in an image, comprising: a converging lens group having an optical zoom mechanism; an imaging element for receiving an input image taken by using the converging lens group having an optical zoom mechanism; a zoom position acquiring device configured to acquire a zoom position representing a lens position condition of the optical zoom mechanism on taking an input image; a coordinate designating device configured to designate coordinates of a pixel, which is an object for distortion correction; a parameter decoding device configured to calculate correction parameters corresponding to the coordinates designated by the coordinate designating device and to the zoom position acquired by the zoom position acquiring device according to the correction parameters for distortion correction, compressed in a zooming direction, in which the lens position condition changes in the optical zoom mechanism, and in a horizontal direction and a vertical direction of the image whose distortion has been corrected, by interpolation calculation; and an image correction device configured to correct distortion of the input image according to the correction parameters calculated by the parameter decoding device; wherein, when a correction process in the horizontal direction is performed on data of one line, the parameter decoding device performs interpolation calculation on the correction parameters, which are needed for performing the process on the data of one line and correspond to the zooming direction and the vertical direction, according to the zoom position and vertical coordinates corresponding to the one line in a horizontal retrace period, and further performs, in an image effective period after the termination of this horizontal retrace period, interpolation calculation on each of pixels arranged in a horizontal direction by using the correction parameters calculated and compressed in the horizontal direction, wherein the parameter decoding device comprises: an interpolation calculation device configured to calculate interpolation calculation according to a phase coefficient by using the inputted and compressed correction parameters; an Y-X-compressed data holding device configured to temporarily hold the correction parameters, which are interpolated in a zooming direction by the interpolation calculation device and needed for distortion correction of data of one line; an X-compressed data holding device configured to temporarily hold the correction parameters, which are interpolated in a vertical direction by the interpolation calculation device and needed for distortion correction of data of one line; an input selection device configured to selectively input to the interpolation calculation device the correction parameters that are compressed in the horizontal direction, the vertical direction and the zooming direction and correspond to the zoom position, the correction parameters read from the Y-X-compressed data holding device, and the correction parameters read from the X-compressed data holding device; and a control device configured to control a selecting operation in the input selection device according to the coordinates designated by the coordinate designating device, and to the zoom position acquired by the zoom position acquiring device, for calculating a phase coefficient, and for supplying the calculated phase coefficient to the interpolation calculation device.