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卷 45, 编号 4 (2019)

Article

A Nonlocal Image Denoising Algorithm Using the Structural Similarity Metric

Dovganich A., Krylov A.

摘要

A new image denoising algorithm is proposed. It is a version of the nonlocal means (NLM) algorithm and uses a metric based on the CMCS modification of the structural similarity index (SSIM). The potentials of this metric for constructing the weighting function in the NLM method using the decomposition of this metric into components and specifying a physically justified weighting function for each component are demonstrated. The results produced by the modified method are compared with the results produced by the basic NLM algorithm, which uses the metrics L2 and SSIM for calculating the metric weights.

Programming and Computer Software. 2019;45(4):141-146
pages 141-146 views

Discomfort of Visual Perception in Virtual and Mixed Reality Systems

Zhdanov A., Zhdanov D., Bogdanov N., Potemin I., Galaktionov V., Sorokin M.

摘要

The importance of the topic of this paper is caused by the rapid development of virtual, mixed, and augmented reality systems. A problem in designing virtual reality (VR), augmented reality (AR) and mixed reality (MR) systems is the assessment of the visual perception of the result, in particular, the assessment of discomfort caused either by differences in the illumination conditions of objects in the real and virtual worlds or by the conflict of the vergence and accommodation of vision of the device user. The standard optical characteristics, such as aberration, frequency and contrast characteristic, and others are not applicable to evaluating the discomfort of visual perception. On the other hand, the discomfort can be assessed using a real proptotype; however, its fabrication can be labor consuming and expensive. We propose methods for virtual prototyping of visual optical systems that can be used in designing AR, VR, and MR devices for the analysis of discomfort caused, for example, by the vergence–accommodation conflict in virtual and augmented reality systems or by differences in the illumination conditions of real and virtual scene objects in mixed reality systems.

Programming and Computer Software. 2019;45(4):147-155
pages 147-155 views

Visualization Methods and Algorithms for Graph Representation of Functional Programs

Kasyanov V., Zolotukhin T., Gordeev D.

摘要

This paper is devoted to the visualization of intermediate representations (the so-called IR graphs) of programs in the Cloud Sisal functional language for the cloud parallel programming system (CPPS). The IR graph represents the data flow in the Cloud Sisal program; it is a hierarchical graph whose vertices correspond to simple and composite expressions and are connected by edges through the vertex ports corresponding to the operands of the expressions (arguments and results). An efficient algorithm for two-dimensional IR graph visualization is proposed. We also describe an efficient implementation of a drawing algorithm for arbitrary attributed hierarchical port graphs in the Visual Graph system. Some methods for IR graph visualization and dynamic modification as applied to Cloud Sisal program debugging are considered.

Programming and Computer Software. 2019;45(4):156-162
pages 156-162 views

A Distributed Tracking Algorithm for Counting People in Video

Kuplyakov D., Shalnov E., Konushin V., Konushin A.

摘要

The problem of tracking people in a video stream with the aim of counting them is studied. Modern video surveillance systems, such as the Moscow video surveillance system, use hundreds of thousands of cameras. The use of modern methods developed for working on a single computer with an expensive graphical processor is economically inefficient for such large-scale systems. In this paper, a distributed tracking algorithm is proposed. It makes it possible to reduce the amount of computational resources due to detecting people in a sparse set of frames. The detection is performed on servers installed in a data center, while the video stream is processed by local camera computation nodes. The experimental evaluation showed that the proposed algorithm provides acceptable quality at the detection rate of 4/3 Hz.

Programming and Computer Software. 2019;45(4):163-170
pages 163-170 views

Detection of Brain Cells in Optical Microscopy Based on Textural Features with Machine Learning Methods

Nosova S., Turlapov V.

摘要

The problem of detecting neurons in optical microscopy is considered by the example of Nissl-stained mouse brain slices. The proposed algorithm consists of the following steps: preprocessing, textural feature extraction, pixel classification, and pixel clustering. When solving this problem, we investigate various preprocessing methods, machine learning algorithms, and textural features. At the classification step, the k nearest neighbor (kNN) algorithm or the naive Bayes classifier (NBC) is used to determine whether each pixel of the image belongs to the neuron’s cell body. In this paper, we investigate textural features of two types: features based on the normalized histogram and features based on the gray level co-occurrence matrix (GLCM). To find the centers of the neurons, all pixels that belong to the neurons are clustered using the mean shift algorithm. It is shown that the best detection quality (precision = 0.82, recall = 0.92, and F1 = 0.86) is achieved with GLCM-based features and neighborhood radius R = 6. It is also shown that the selection of different preprocessing algorithms significantly affects the detection result. In terms of detection quality, the kNN algorithm outperforms the NBC. On the dataset used, the selection of the parameter k > 15 does not significantly improve the quality of detection. The proposed method yields the result similar to that achieved in [1]: Recall(A) = 865%. In sampling tests on some microscopy images from the Broad Bioimage Benchmark Collection (BBBC), the proposed approach shows the best or equivalent quality in detecting the number of cells on the image. For detection, the algorithm uses only local textural features, which removes restrictions on the parallelization of computations.

Programming and Computer Software. 2019;45(4):171-179
pages 171-179 views

Adaptive Scientific Visualization Tools for a Smart Paleontological Museum

Ryabinin K., Kolesnik M.

摘要

This paper is devoted to the development of tools that allow museum workers to create interactive exhibits by using the Internet of Things (IoT) technology. We propose a unified software and hardware solution that enables the users who do not have deep knowledge in electronics and programming to assemble and interconnect various devices by the principle of a construction set. This, in turn, makes it possible to implement the concept of Smart Museum without the involvement of third-party IT specialists and large investments. The hardware part of the proposed solution is based on the ESP8266 programmable microcontroller with a built-in WiFi module. Peripheral devices can be connected to this microcontroller via expansion boards, the so-called shields. The software part of the solution is based on the SciVi adaptive multiplatform scientific visualization system. This system is fully controlled by the ontological knowledge base and provides the user with a high-level graphical interface that allows him or her to describe visualization algorithms by using data flow diagrams (DFDs). In this work, the SciVi system is supplemented with a mechanism that automatically generates firmware for IoT devices. It is based on an electronic component ontology that describes these devices and their programming methods. The firmware code generator controlled by this ontology automates the creation of lightweight embedded SciVi copies, which are installed on IoT devices and act as servers for data collection, processing, and visualization. To test the proposed solution, we created an interactive exhibit of Dimetrodon grandis, an extinct species of synapsids that lived during the Early Permian.

Programming and Computer Software. 2019;45(4):180-186
pages 180-186 views

Level of Detail for Precomputed Procedural Textures

Sanzharov V., Frolov V.

摘要

In this paper we address the problem of determining the detail level of precomputed procedural textures for photorealistic rendering. We propose an approach based on a fast preliminary scene visualization with level of detail calculation based on mip-mapping. Proposed solution was tested for computing resolution of different types of procedural textures and image textures.

Programming and Computer Software. 2019;45(4):187-195
pages 187-195 views

Algorithms and Software Increasing the Efficiency of Processing Multidimensional Heterogeneous Data

Zakharova A., Nebaba S., Zavyalov D.

摘要

An algorithm of methods selection for processing multidimensional heterogeneous data based on the general properties of the data used and the methods included in the review is proposed in this paper. The algorithm is implemented in the form of software and a group of interpolation algorithms is compared by the example of the problem of constructing a 3D human face model for a person’s recognition system. It is shown that the proposed algorithm for selecting data processing methods works successfully for a group of data interpolation methods.

Programming and Computer Software. 2019;45(4):196-201
pages 196-201 views

To the Development of Open Source Software for the Reconstruction of CAD Models

Slyadnev S., Turlapov V.

摘要

In this paper, we describe an open source software package aimed at solving reverse engineering problems for CAD models defined in polygonal form. We briefly discuss the main principles behind the new software, its architecture, and directions for its further development. The use of the software is illustrated by examples of a turbine blade. In the first example, the turbine blade is reconstructed automatically from a structured point cloud. Another example is the interactive reconstruction of the turbine blade from an unstructured surface triangulation. In both the cases, we use a surface skinning strategy enhanced by a curve fairing operator. We show that the modified skinning operator does not minimize the total bending energy of the surface, but yields a smooth patch where input inaccuracies are compensated for. The reconstruction result is a parametric model of the turbine blade where the design variables are the coordinates of the poles for each profile curve. The proposed software architecture can be used for partial or complete parameterization of reconstructed CAD models with the aim of their subsequent optimization.

Programming and Computer Software. 2019;45(4):202-212
pages 202-212 views

Methods of Gait Recognition in Video

Sokolova A., Konushin A.

摘要

Human gait is an important biometric index that allows to identify a person at a great distance without direct contact. Due to these qualities, which other popular identifiers such as fingerprints or iris do not have, the recognition of a person by the manner of walking has become very common in various areas where video surveillance systems can be used. With the development of computer vision techniques, a variety of approaches for human identification by movements in a video appear. These approaches are based both on natural biometric characteristics (human skeleton, silhouette, and their change during walking) and abstract features trained automatically which do not have physical justification. Modern methods combine classical algorithms of video and image analysis and new approaches that show excellent results in related tasks of computer vision, such as human identification by face and appearance or action and gesture recognition. However, due to the large number of conditions that can affect the walking manner of a person itself and its representation in video, the problem of identifying a person by gait still does not have a sufficiently accurate solution. Many methods are overfitted by the conditions presented in the databases on which they are trained, which limits their applicability in real life. In this paper, we provide a survey of state-of-the-art methods of gait recognition, their analysis and comparison on several popular video collections and for different formulations of the problem of recognition. We additionally reveal the problems that prevent the final solution of gait identification challenge.

Programming and Computer Software. 2019;45(4):213-220
pages 213-220 views
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