New Results on the Projection Filter
نویسنده
چکیده
The projection filter is an approximate nonlinear filter based on orthogonal projection in the tangent space of a manifold of densities. The Riemannian metric used is the Fisher information metric. In this paper it is shown that if one uses Gaussian densities the projection filter equals a McShane-Fisk-Stratonovich version of the socalled Assumed Density Filter.
منابع مشابه
Utilization of an optimum low-pass filter during filtered back-projection in the reconstruction of single photon emission computed tomography images of small structures
Introduction:Low-pass filters eliminate noise, and accordingly improve the quality of filtered back-projection (FBP) in the reconstruction of single photon emission computed tomography (SPECT) images. This study aimed at selection of an optimum low-pass filter for FBP reconstruction of SPECT images of small structures. Material and Methods:Sp...
متن کاملComparisons of Hounsfield Unit Linearity between Images Reconstructed using an Adaptive Iterative Dose Reduction (AIDR) and a Filter Back-Projection (FBP) Techniques
Background: The HU linearity is an essential parameter in a quantitative imaging and the treatment planning systems of radiotherapy. Objective: This study aims to evaluate the linearity of Hounsfield unit (HU) in applying the adaptive iterative dose reduction (AIDR) on CT scanner and its comparison to the filtered back-projection (FBP).Material and Methods: In this experimental phan...
متن کاملA Family of Selective Partial Update Affine Projection Adaptive Filtering Algorithms
In this paper we present a general formalism for the establishment of the family of selective partial update affine projection algorithms (SPU-APA). The SPU-APA, the SPU regularized APA (SPU-R-APA), the SPU partial rank algorithm (SPU-PRA), the SPU binormalized data reusing least mean squares (SPU-BNDR-LMS), and the SPU normalized LMS with orthogonal correction factors (SPU-NLMS-OCF) algorithms...
متن کاملImage Restoration with Two-Dimensional Adaptive Filter Algorithms
Two-dimensional (TD) adaptive filtering is a technique that can be applied to many image, and signal processing applications. This paper extends the one-dimensional adaptive filter algorithms to TD structures and the novel TD adaptive filters are established. Based on this extension, the TD variable step-size normalized least mean squares (TD-VSS-NLMS), the TD-VSS affine projection algorithms (...
متن کاملDetermination of the optimum filter for qualitative and quantitative 99mTc myocardial SPECT imaging
Background: Butterworth, Gaussian, Hamming, Hanning, and Parzen are commonly used SPECT filters during filtered back-projection (FBP) reconstruction, which greatly affect the quality and size accuracy of image. Materials and Methods: This study involved a cardiac phantom in which 1.10 cm thick cold defect was inserted into its myocardium wall and filled with 4.0 μCi/ml (0.148 MBq/ml) 99mTc conc...
متن کاملApplication of the Min-Projection and the Model Predictive Strategies for Current Control of Three-Phase Grid-Connected Converters: a Comparative Study
This paper provides a detailed comparative study concerning the performance of min-projection strategy (MPS) and model predictive control (MPC) systems to control the three-phase grid connected converters. To do so, first, the converter is modeled as a switched linear system. Then, the feasibility of the MPS technique is investigated and its stability criterion is derived as a lower limit on th...
متن کامل