Rectifying camera pairs

摘要

The quality of stereoscopic imaging using cameras with wide angle lenses can be improved using various calibration approaches to determine distortions or misalignments between the cameras. A calibration object such as a checkered grid with a determined inclination between portions can be used to provide lateral calibration as well as depth information. Intersections of the checkered regions can be used to determine intersection points for the calibration object in the image. Regions about at least a portion of these points can be analyzed, where the regions are sized such that features of the calibration object are substantially linear. Nearest neighbor points can be identified, and a local orientation determined in order to determine a relationship of each of the nearest points. Once identified, the points in each image can be correlated to corresponding points of the calibration object.

主权项

1. A computer-implemented method, comprising:
capturing a first image including a first representation of a calibration object using a first camera; capturing a second image including a second representation of the calibration object using a second camera separated a distance from the first camera, the calibration object including a pattern of alternating regions; locating respective points in each of the first image and the second image corresponding to intersections of the alternating regions of the pattern; for each point of at least a portion of the respective points in each of the first image and the second image:
analyzing a region including the point to identify nearest neighboring points, a size of the region being determined such that a respective measure of straightness of intersecting lines intersecting at the point is less than or greater than a predetermined measure of straightness by at most a specified value and such that an angle of the intersecting lines is less than or greater than ninety degrees by at most a specified number of degrees;determining a respective relationship of the nearest neighboring points relative to the point;determining a local orientation of the nearest neighboring points relative to a default coordinate system; anddetermining a respective correlation of each of the nearest neighboring points with a corresponding point on the calibration object based at least in part upon the respective relationship of the nearest neighboring points relative to the point and the local orientation of the nearest neighboring points; and storing information from the respective correlation for reducing at least one of misalignment or distortion effects from subsequent pairs of images captured by the first camera and the second camera, each subsequent pair of images capable of being used to generate a stereoscopic image display.