Lee T S, Min B G
Department of Biomedical Engineering, College of Medicine, Seoul National University, South Korea.
Med Phys. 1991 Nov-Dec;18(6):1132-40. doi: 10.1118/1.596621.
A dual sensor Wiener filter (DSWF) technique was used to improve the image quality of a scanning type digital radiographic system. In a digital radiographic system, image quality is evaluated by resolution and SNR (signal-to-noise ratio), which are two important parameters representing the objective performance of the system. In this method, when two images are acquired in the same region using two sensors with different characteristics of resolution and SNR, they are processed simultaneously using DSWF, which is the extended concept of a Wiener filter to two dimensions. DSWF uses the cross power spectrum between dual sensor outputs of the same chest radiographic image in the design of filter parameters. It has been implemented with fast algorithm using FFT (fast Fourier transform). The performance of the proposed method is compared with that of conventional methods (Wiener filter and parametric projection filter). In simulation studies, it is shown in 12 cases that this new method has SNR improvement of 1-2 dB better than conventional methods.
一种双传感器维纳滤波器(DSWF)技术被用于提高扫描型数字射线照相系统的图像质量。在数字射线照相系统中,图像质量通过分辨率和信噪比(SNR)来评估,这是代表系统客观性能的两个重要参数。在该方法中,当使用具有不同分辨率和信噪比特性的两个传感器在同一区域采集两幅图像时,它们会使用DSWF同时进行处理,DSWF是维纳滤波器到二维的扩展概念。DSWF在滤波器参数设计中使用同一胸部射线照相图像的双传感器输出之间的交叉功率谱。它已通过使用快速傅里叶变换(FFT)的快速算法实现。将所提方法的性能与传统方法(维纳滤波器和参数投影滤波器)的性能进行了比较。在模拟研究中,在12个案例中表明,这种新方法的信噪比提高比传统方法高1 - 2 dB。