US 5,675,380 A · Device for forming an image and method of correcting geometrical optical distortions in an image

Abstract

The device includes systems for picking up (1), acquiring (2) and digitizing (3) a distorted source image (SI), a system for processing digital images (4, 47) for constructing a distortion-corrected target image (TI) corresponding to the source image (SI), this system including a first sub-assembly (4) for predetermining, on the basis of the data of a distorted TEST source image (SG.degree.), an optical center (OC.sup.n) and a polynomial function (F.sub.n) for correcting radial distortions around this optical center, and a second sub-assembly (47) which applies the polynomial correction function to each address of the pixel of the target image (TI) for furnishing the address of a point in the distorted source image (SI) in which an intensity data is present which is applied to the initial address in the target image. The method includes the computation, in a TEST source image (SG.degree.), of an optical center (OC.sup.n) at the center of optical distortions, and of a polynomial function (F.sup.n) for correcting distortions for constructing a TEST target image (TI).

Claims11

Dependent claims

A device for forming an image, comprising:

a camera system;
a system for acquisition of data of a source image distorted by the camera system;
a system for digitizing said source image including a first image memory for storing intensity data of each pixel marked by an address in a bidimensional matrix;
and
a system for processing the digital image for constructing a distortion-corrected target image corresponding to the source image,
in which the image processing system includes:
a first sub-assembly for predetermining, on the basis of image data of a distorted TEST source image, an optical center and a polynomial function for correcting radial distortions around said optical center;
and
a second sub-assembly including a memory for storing the optical center and the polynomial function determined by the first sub-assembly, a computing block for applying the polynomial function to each pixel address of the target image, and for supplying an address of a pixel in the distorted source image in which an intensity data is present which is to be applied to the initial address in the target image, and a second image memory for storing data of the target image.

6 more elements

A method of correcting geometrical optical distortions produced in an image by a camera system, said method comprising the preliminary steps of:

a) acquiring data and digitizing a TEST source image, including storing intensity data of each pixel marked by an address in a bidimensional matrix;
b) estimating an optical center located, at best, at the optical distortion center of the TEST source image and the ratio of said optical center computed in a digital image to be constructed, referenced TEST target image representing the corrected TEST source image of the optical distortions;
and
c) estimating a polynomial function for causing the address of a corresponding point, denoted reference point, in the distorted TEST source image to correspond to the address of a pixel in the corrected TEST target image, based on the hypothesis that the geometrical optical distortions in the TEST source image are radial around the distortion center, so that said corresponding points are aligned, at best, with the estimated optical center.

1 more element

Dependencies are inferred from the claim text.

Device for forming an image and method of correcting geometrical optical distortions in an image

Life of this patent

Device for forming an image and method of correcting geometrical optical distortions in an image

Life of this patent

Abstract

Claims11