一种基于基本色系的自动白平衡方法

摘要

在不含黑、灰、白的单色背景下，基于灰度世界模型的白平衡方法容易导致色彩失真严重，今对此提出了一种基于基本色系的自动白平衡方法：通过研究不同色温下颜色分量比值“R／G”与“B／G”的关系，得到单一色系下颜色分量比值关系的特征函数。据此，在“R／G”与“B／G”关系已知的情况下估算出单色背景所在的色温，将该色温映射到白色系特征函数上，并利用插值算法得到该单色背景的白平衡参数。对校正后图像的色差作客观比较，结果表明该方法能够弥补传统灰度世界方法的缺陷，明显改善单色背景下的色彩失真。%In the absence of black , gray and w hite monochrome background , w hite balance method based on grey world model can easily lead to serious color distortion ;therefore ,this paper presents an automatic w hite balance method based on color schemes .T hrough studying the relationship between “R/G” and“B/G” ,which represents the color component ratio under different color temperatures ,the characteristic function of the color component ratio under the specific monochrome background is obtained .With this characteristic function and the know n relationship between aimed “R/G” and “B/G” , the color temperature of the aimed monochromatic background can be estimated .After that ,this estimated color temperature is mapped to the characteristic function of w hite color scheme ; therefore , w hite balance parameters of the aimed monochromatic background can be calculated by the interpolation method .By comparing the color deviation of the corrected image objectively ,it is sure that this method can make up for the traditional white balance method based on the grey world model , and the color distortion of aimed monochromatic background can be improved obviously .