In practical vision systems, due to the limitation of manufacturing technology, charge-coupled device pixel cells are difficult to satisfy the standard square, and the lens inevitably has imaging nonlinearity, which leads to geometric distortion of the image. To ensure the accuracy of subsequent visual processing, it is necessary to correct the image distortion. A non-metric correction method for complete lens distortion using dual-characteristics joint measurement is proposed. We not only considered the influence of the distortion center in the correction process but also constructed a mapping matrix to standardize the pixel cells, thus establishing a complete lens distortion model. Simultaneously, the linear residual function of the dual-characteristics joint measurement was defined according to the geometric constraint between the vanishing point and the straightness. In addition, the distortion model coefficients were determined by nonlinear iterative optimization. Extensive experiment results demonstrated that the proposed method enables effective and accurate lens distortion correction, which is significantly superior to the existing single characteristic measurement distortion correction approach. |
ACCESS THE FULL ARTICLE
No SPIE Account? Create one
Distortion
Image processing
Optical engineering
3D modeling
Lithium
Cameras
Imaging systems