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41.
杨秀朋 《重庆科技学院学报(自然科学版)》2012,14(5):154-157
介绍FIR滤波器的基本原理以及满足线性相位的条件,阐述了FIR滤波器的生成.从MATLAB得到的滤波器实现了在嵌入式中的移植,并进行了计算优化.通过对含有噪声的数据处理结果表明,该方法在工程实践中能满足要求. 相似文献
42.
Multiple human tracking in high-density crowds 总被引:1,自引:0,他引:1
In this paper, we introduce a fully automatic algorithm to detect and track multiple humans in high-density crowds in the presence of extreme occlusion. Typical approaches such as background modeling and body part-based pedestrian detection fail when most of the scene is in motion and most body parts of most of the pedestrians are occluded. To overcome this problem, we integrate human detection and tracking into a single framework and introduce a confirmation-by-classification method for tracking that associates detections with tracks, tracks humans through occlusions, and eliminates false positive tracks. We use a Viola and Jones AdaBoost detection cascade, a particle filter for tracking, and color histograms for appearance modeling. To further reduce false detections due to dense features and shadows, we introduce a method for estimation and utilization of a 3D head plane that reduces false positives while preserving high detection rates. The algorithm learns the head plane from observations of human heads incrementally, without any a priori extrinsic camera calibration information, and only begins to utilize the head plane once confidence in the parameter estimates is sufficiently high. In an experimental evaluation, we show that confirmation-by-classification and head plane estimation together enable the construction of an excellent pedestrian tracker for dense crowds. 相似文献
43.
《国际计算机数学杂志》2012,89(2):254-263
This paper focuses on the construction and properties of spline dyadic wavelet that equals its reconstruction wavelet. A general construction method of finite spline dyadic low-pass and high-pass filters is given. It proves that finite spline dyadic low-pass filters are symmetric about 0 or 1/2, but there are no finite spline high-pass filters possessing symmetry with respect to 0 or 1/2. It further shows that there exist infinite spline high-pass filters possessing symmetry with respect to 0 or 1/2, which can be constructed. Their energy is concentrated and so finite symmetric spline dyadic wavelet filter that equals its reconstruction filter can be obtained approximately. Construction examples for quadratic and cubic spline dyadic wavelet filters are given. 相似文献
44.
基于Matlab/Simulink平台,给出了滚升余弦滤波器和眼图的具体实现方法及流程。以FIR滤波器为基本模块构造了滚升余弦滤波器基本模型,并通过改变滚降系数对滚升余弦滤波器的性能作出分析,验证了方案的可行性。 相似文献
45.
为了研究自适应滤波在噪声消除,干扰抑制以及雷达信号处理中的广泛应用,对滤波器各影响因素进行了分析,提出了各参数的设计规则.以自适应滤波理论为基础,将信号划分成不同的子带通过原型分析综合滤波器组,将处理后的各路信号叠加可恢复原信号.选择合理的参数设置滤波器可以使系统的综合性能最优,同时可以将信号在传输过程中造成的损失减小到最低.通过大量仿真验证了该参数选取规则的准确性和有效性. 相似文献
46.
采用三维时域有限差(finite-difference time—domain,FDTD)算法模拟了由十字叉形开口的金膜周期结构组成的红外带通滤波器光谱性能。该算法采用Z变换技术利用Lorentz-Drude模型、Drude模型和理想导体模型描述了金膜在红外频率的介电常数,模拟了红外带通滤波器的透射性能,同测量结果进行了比较.结果表明,利用Lorentz—Drude模型计算的透射率同测量数据吻合得起好。 相似文献
47.
Ali Kircay Ugur Cam 《AEUE-International Journal of Electronics and Communications》2006,60(6):471-474
This paper proposes a first-order allpass log-domain filter, which is systematically derived using the state-space synthesis procedure. To the best knowledge of the authors, the filter is the first log-domain first-order allpass filter in the literature. The proposed filter has a simple structure and can be electronically tuned. PSPICE simulations are given to confirm the theoretical analysis. 相似文献
48.
49.
A conjugate filter oscillation reduction scheme originally developed for compressible flows and in general for hyperbolic conservation laws is applied to the solution of the incompressible Navier-Stokes equation with periodic boundary conditions. Conjugate low-pass and high-pass filters are constructed by using a local spectral method, the discrete singular convolution algorithm. A spectral-like resolution, i.e., near the machine precision obtained at a sampling rate close to the Nyquist limit (2 points per wavelength), is achieved in treating a smooth initial value problem which admits an exact solution. The spectral-like resolution is enhanced by the use of conjugate low-pass filters in treating the double shear layer and multi-shear layer problems, which exhibit extremely small flow features. 相似文献
50.
We propose to use adaptive wavelet lifting for image retrieval systems that are based on shape detection and multiresolution structures of objects in a database against a background of texture. To measure the performance of our approach, feature vectors are computed based on moment invariants of detail coefficients produced by the adaptive lifting scheme and retrieval rates are obtained by measuring distances between these vectors. Retrieval rates are compared with the rates obtained when using non-adaptive wavelet filtering as a preprocessing step. A synthetic database is created for this simulation. 相似文献