摘要
传统全变分算法在变分过程中多数会受到阶梯效应的影响,导致重构图像出现纹理缺失和过平滑。为此,提出一种基于改进非局部均值的重构算法。通过引入分数阶梯度模型保留图像纹理信息,利用非局部均值滤波法更新拉格朗日梯度算子,从而降低计算复杂度。实验结果表明,与传统TVAL3算法相比,该算法能够有效减少运行时间,具有较好的重构性能。
The traditional total variation algorithm is mostly affected by the staircase effect in the variation process,so it causes texture loss and over-smoothing in the reconstructed image.Therefore,a reconstruction algorithm based on improved non-local means is proposed.The image texture information is preserved by introducing a fractional step model,and the Lagrangian gradient operator is updated by the non-local means filtering method,thereby reducing the computational complexity.Experimental results show that compared with the traditional TVAL3 algorithm,this algorithm can effectively reduce the running time and has better reconstruction performance.
引文
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