一种改进的多点融合非均匀校正技术

An Improved Non-uniformity Calibration Technology with Multi-position Fused Data

针对空间宽幅相机在进行非均匀性校正过程中相机镜头与积分球输出口的相对位置发生变换后非均匀性校正精度下降的原因进行了分析,提出了一种改进的融合多点位置的非均匀校正新方法,即为了消除积分球的角均匀性和面均匀性的不足,采用获取多个位置的大量定标图像,融合求取平均值的方法得到校正系数来削弱这种影响,并进行试验验证分析。结果表明,多点融合的校正方法在积分球输出口光强不均匀、又无法固定相机与积分球相对位置的前提下,减少了积分球光强的不均匀性对系数可靠性的影响,相对辐射定标的非均匀校正精度得到大幅提高。

The calibration accuracy declines when there is relative location change between the camera and the integrating sphere in the process of non-uniformity calibration.A new method of relative radiometric calibration using multi-position fused data was proposed.To eliminate the shortcoming of angular and facial non-uniformity of the integrating sphere,the calibration coefficients were obtained by a lot of images from multi-positions.Experiment results show that the proposed method can decrease the effect of non-uniformity of the sphere light intensity on the calibration coefficients,under the condition that the light intensity of the integrating sphere is uneven and the relative position between the camera and the sphere can not be fixed.This new method can improve the non-uniformity calibration accuracy.