Kumar M, Mishra S K
Department of Electrical and Electronics Engineering, Birla Institute of Technology, Mesra, Ranchi-835215, India.
Biomed Mater Eng. 2017;28(6):643-654. doi: 10.3233/BME-171702.
The clinical magnetic resonance imaging (MRI) images may get corrupted due to the presence of the mixture of different types of noises such as Rician, Gaussian, impulse, etc. Most of the available filtering algorithms are noise specific, linear, and non-adaptive.
There is a need to develop a nonlinear adaptive filter that adapts itself according to the requirement and effectively applied for suppression of mixed noise from different MRI images.
In view of this, a novel nonlinear neural network based adaptive filter i.e. functional link artificial neural network (FLANN) whose weights are trained by a recently developed derivative free meta-heuristic technique i.e. teaching learning based optimization (TLBO) is proposed and implemented.
The performance of the proposed filter is compared with five other adaptive filters and analyzed by considering quantitative metrics and evaluating the nonparametric statistical test. The convergence curve and computational time are also included for investigating the efficiency of the proposed as well as competitive filters.
The simulation outcomes of proposed filter outperform the other adaptive filters. The proposed filter can be hybridized with other evolutionary technique and utilized for removing different noise and artifacts from others medical images more competently.
临床磁共振成像(MRI)图像可能会因存在诸如莱斯噪声、高斯噪声、脉冲噪声等不同类型噪声的混合而受到损坏。大多数现有的滤波算法是针对特定噪声的、线性的且非自适应的。
需要开发一种非线性自适应滤波器,它能根据需求自行调整,并有效地用于抑制来自不同MRI图像的混合噪声。
鉴于此,提出并实现了一种基于新型非线性神经网络的自适应滤波器,即功能链接人工神经网络(FLANN),其权重由最近开发的无导数元启发式技术即基于教学学习的优化(TLBO)进行训练。
将所提出滤波器的性能与其他五种自适应滤波器进行比较,并通过考虑定量指标和评估非参数统计检验进行分析。还包括收敛曲线和计算时间,以研究所提出的滤波器以及竞争滤波器的效率。
所提出滤波器的模拟结果优于其他自适应滤波器。所提出的滤波器可以与其他进化技术相结合,并更有效地用于从其他医学图像中去除不同的噪声和伪影。