Image processing apparatus, image processing system, imaging apparatus and image processing method

An image processing system for receiving an input image taken by a converging lens group having an optical zoom mechanism and for correcting distortion of the image, the image processing system comprising:

• zoom position acquiring means for acquiring a zoom position indicating a lens position condition of the optical zoom mechanism on taking an input image;
• zooming-direction encoding means for compressing correction parameters for distortion correction, which correspond to each of a lens position condition by utilizing zoom petitioning points at which lens position conditions in the optical zoom mechanism are serially partitioned between a wide-end and a tele-end into plural levels including both the ends;
• zooming-direction decoding means for decompressing the correction parameters corresponding to the zoom position acquired by the zoom position acquiring means by interpolation calculation according to the zoom compression parameters compressed by the zooming-direction encoding means;
• and
• image correction means for correcting distortion of the input image according to the correction parameters decompressed by the zooming-direction decoding means.

An imaging apparatus for imaging an image by using a converging lens group having an optical zoom mechanism, the imaging apparatus comprising:

• zoom position detecting means for detecting a zoom position indicating a lens position condition of the optical zoom mechanism on taking an input image;
• zooming-direction decoding means for decompressing correction parameters, which corresponds to the zoom position detected by the zoom position detecting means, by interpolation calculation according to the zoom compression parameter obtained by compressing the correction parameters for distortion correction, which correspond to each of a lens position condition, through utilization of zoom petitioning points at which lens position conditions in the optical zoom mechanism are serially partitioned between a wide-end and a tele-end into plural levels including both the ends;
• and
• image correction means for correcting distortion of the imaged image according to the correction parameters decompressed by the zooming-direction decoding means.

An image processing method for receiving an inputted image, which is taken by using a converging lens group having an optical zoom mechanism, and for correcting distortion of the image, the image processing method comprising the steps of:

• acquiring a zoom position representing a lens position condition of the optical zoom mechanism on taking an inputted image;
• decompressing the correction parameter associated to the zoom position according to a zoom compression parameter, into which a correction parameter for distortion correction corresponding to each lens position condition is compressed by utilizing zoom partitioning points at which lens position conditions of the optical zoom mechanism are sequentially partitioned into plural levels that are set between a wide-end and a tele-end and that include both the ends;
• and
• correcting distortion of the inputted image according to the decompressed correction parameter.