采用三次相位板进行景深延拓的波前编码系统得到非对称的点扩展函数。为了获得最终清晰的彩色图像，研究了一种基于广义极小残差法(GMRES)的迭代算法，结合Tikhonov规整化方法，并利用多通道处理过程对中间图像进行去卷积恢复。为了消除恢复图像边界的振铃效应，推导了新的光学成像过程数学模型，该模型采用反镜像边界条件并利用直积近似对卷积核进行处理。模拟数据的分析表明，采用多通道处理过程对彩色图片进行恢复时，新的算法在给出精确的反卷积结果的同时能有效地抑制噪声的放大;实验结果显示，较之经典的维纳滤波恢复结果，新算法能够更好的消除边界的振铃和图像边缘的振动波纹。

The cubic phase mask is used to extend the depth of field in a wavefront coding system,the point spread function is asymmetric. We research a new iteration algorithm to get the final sharp color image,which based on the GMRES (generalized minimal residual methods) combined with the regularization method and multichannel processing procedure. In order to eliminate the ringing effect,Antireflective boundary conditions and Kronecker product approximation is used for the new image formation. Analysis and the simulation show that the new algorithm can give excellent deconvolution results and suppress the noise magnification effectively. From the experimental result,this new algorithm can give better results than classic Wiener filtering with little ringing effect on the image border and little vibration on the edge.