A Distortion Correction Method for Line Scan Camera Based on Orthogonal Pixel Equivalent Ratio

Abstract

A line camera distortion correction method based on the orthogonal pixel equivalent ratio, by analyzing the line camera imaging model, deduces the theory that the pixel equivalent ratio in the orthogonal direction is constant under the ideal lens, and finally obtains the distortion parameters of the line camera. The specific steps are to first find the corner points on the checkerboard picture, secondly take the corner points of two adjacent rows arbitrarily, derive their undistorted coordinate expressions, and then find the x-axis and The pixel equivalent value in the y-axis direction, and then obtain the objective function to be optimized according to the theory that the pixel equivalent ratio in the orthogonal direction under the ideal lens is constant, and finally use the nonlinear optimization method to obtain the distortion parameters. The method of the invention can obtain the vertical stretch ratio of the picture at the same time without secondary correction, so the calculation amount is smaller, the stability is good, and the implementation conditions are easy to achieve.

Description

technical field [0001] The invention belongs to the technical field of image processing, and relates to a camera distortion correction technology, in particular to a line array camera distortion correction method based on an orthogonal pixel equivalent ratio. Background technique [0002] The linear array camera is simple in structure, low in cost and high in resolution, and has gained more and more applications in non-contact real-time measurement systems, surface defect detection systems, and high-speed moving target attitude measurement systems. In applications such as high-precision dimensional measurement and linear array binocular vision, the presence of lens distortion can seriously affect system performance. Therefore, it is necessary to calibrate and compensate the camera lens distortion in the line scan camera vision system with high requirements. [0003] At present, the research on the lens distortion theory of the area array camera is relatively mature. Both Zh...

Images