A basic study for a robotic transfer aid system based on human motion analysis

A metal hydride (MH) actuator uses the reversible reaction between heat energy and mechanical energy of a hydrogen-absorbing alloy and moves smoothly without any noise. Moreover, the actuator is compact, light and has adequate compliance. In this paper, some experiments concerning human motion patterns were carried out in order to adopt the MH actuator to the transfer aid system. The results were evaluated from a biomedical engineering viewpoint in order to obtain the optimal parameters for transferring the disabled from a bed to a wheelchair and vice versa (transfer aid). Sagittal plane kinematics, surface electromyographic signals (EMG) obtained from lower limbs, ground reaction forces and foot pressure distribution were measured using a three-dimensional motion analyzer. From the experimental results, it was found that the motion of the transfer aid was smooth when the initial angle of the ankle was 70°. The best initial angle of the trunk was also found to be about 45° while standing from a bed. However, the initial angle of the trunk was best at 60° when a person was in the process of sitting down on a wheelchair. Furthermore, a knee pad which supports the lower limbs requires flexibility in the range of 0.1-0.2 kgf/mm.     

A collaborative face-to-face design support system based on sketching and gesturing

Mobile and pervasive computing has seen a rapid development in the last years. Portable, handheld computing devices are getting more popular as their capabilities increase. Therefore, people having the need to work on-the-field have now the possibility to be supported by computer technology, for example, garden or building designers. Ad-hoc networking capabilities of handheld devices enable the development of supporting tools for collaborative work anywhere. This paper presents MCSketcher, a system that enables face-to-face collaborative design based on sketches using handheld devices equipped for spontaneous wireless peer-to-peer networking. It is especially targeted for supporting preliminary, in-the-field work, allowing designers to exchange ideas through sketches on empty sheets or over a recently taken photograph of the object being worked on, in a brainstorming-like working style. Pen-based designed human–computer interaction is the key to supporting collaborative work. The gestures-based command input results in a lightweight yet efficient and easy to use interface. Graph structured hierarchical documents help to overcome the problems of a small screen size.     

A study on vulnerability and presentation attack detection in palmprint verification system

As biometric systems become ubiquitous in the domain of personal authentication, it is of utmost importance that these systems are secured against attacks. Among various types of attacks on biometric systems, the presentation attack, which involves presenting a fake copy (artefact) of the real biometric to the biometric sensor to gain illegitimate access, is the most common one. Despite the serious threat posed by these attacks, not much work has been done to address this vulnerability in palmprint-based biometric systems. This paper demonstrates the vulnerability of a palmprint verification system to presentation attacks and proposes a novel presentation attack detection (PAD) approach to discriminating between real biometric samples and artefacts. The proposed PAD approach is inspired by a work that established relationship between the surface reflectance and a set of statistical features extracted from the image. Specifically, statistical features computed from the distributions of pixel intensities, sub-band wavelet coefficients and the grey-level co-occurrence matrix form the original feature set, and CFS-based feature selection approach selects the most discriminating feature subset. A trained binary classifier utilizes the selected feature subset to determine whether the acquired image is of real hand or an artefact. For performance evaluation, an antispoofing database—PALMspoof has been developed. This database comprises left- and right-hand images of 104 subjects, and three kinds of artefacts generated from these images. In addition to PALMspoof database, the biometric system’s vulnerability has been assessed on display and print artefacts generated from two publicly available palmprint datasets. Our experimental results show that 1) the palmprint verification system is highly vulnerable with spoof acceptance of 84.56%; 2) the proposed PAD approach is effective against both print and display attacks, in both same-device and cross-device scenarios; and 3) the proposed approach for PAD provides an average improvement of 12.73 percentage points in classification error rate over local binary pattern (LBP)-based PAD approach.     

A microcomputer-based interactive presentation development system

Under the primary sponsorship of the National Aeronautics and Space Administration (NASA), the University of Southwestern Louisiana (USL) NASA PC R&D project is conducting a variety of research activities addressing microcomputer-based support for instructional activities. The Interactive Presentation Development System (IPDS), one product of this research, is intended to minimize the overhead involved in the preparation and presentation of instructional material while significantly increasing instructor control over the dynamics of such presentations. This paper presents a brief overview of the USL NASA PC R&D project, a detailed explanation of IPDS capabilities, and an analysis of IPDS's effect on the instructional presentation process.     

A case study of a two-stage image segmentation algorithm

Multimedia Tools and Applications - Mumford-Shah (MS) model has attracted considerable research interests in the past decades. It is a classical and important approach for image segmentation. In a...     

视频图像识别报警系统的研究

本文是针对于传统报警系统单点监控报警的机械性而设计的智能化、数字化的视频图像识别监控报警系统。该系统对监控场所进行全景监控,如有异物进入,对异物进行分割、测量,从不同的角度)如形状因子)进行了分析和判断,进而判断异物是否有害。     

A multimedia presentation system using a 3D gesture interface in museums

Multimedia presentations have become an indispensable feature of museum exhibits in recent years. Advances in technology have increased the relevance of studying digital communication using computational devices. Devices, such as multi-touch screens and cameras, are essential for natural communication, and obvious applications involve entertainment to attract users. This study focused on the use of cameras to support natural interaction of visitors during museum presentations. We first outlined a platform called the “U-Garden,” comprising a set of tools to assist application designers in developing movement-based projects that employ camera tracking. We then established a rationale with which to base the design of such presentation tools. This system supplies interactive power to natural interaction based on depth image streams, and provides tracking results to designers for producing numerous fascinating applications that appeal to more diverse interactive imaginations.     

A chaos based image steganographic system

This paper presents a steganographic technique using the theory of Brownian motion. In the beginning, the Brownian Based Scrambling procedure introduces traces of non linearity in the carrier medium so as to introduce one layer of security. A lighter pixel (in terms of its intensity) is presumed to experience a faster movement than the heavier ones. The above stated concept is based on the randomized scrambling strategy which is usually chaotic in nature. It actually reflects the strategy of chaos generation in the image medium. The ‘key’ is generated from the Brownian theories and is being utilized in the Power Modulus Scrambling strategy to increase the security level. In addition, the embedding technique, i.e. Pixel Insertion Methodology is also dependent on certain correlation factors of Brownian motion. The performance has been worked out to establish the efficacy of the algorithm. This whole procedure supports high embedding capacity. The experimental results show that the proposed technique performs better or at least at par with respect to many of the existing steganographic techniques. The results have been tested against various benchmarks, as illustrated in the section of experimental results. This approach can be used to provide an additional layer of protection to any system that communicates important data/information through any kind of globally accessed medium. Moreover, this approach serves its purpose of providing seamless security between sender and receiver without producing any distortion in the images. This explicit concept may be used in cyber-security for prevention of unauthorized access of information.     

一种CMOS型的耐辐射图像采集系统

设计并实现了一种基于CMOS型图像传感器的高耐辐射图像采集系统。根据应用环境提出了相应的系统构架,通过FPGA的控制,使各个模块协调工作,完成从辐射区的图像采集到上位机的图像显示的全过程。主要介绍该采集系统的系统构架及控制软件部分,并针对系统中相应的要点及工作中出现的一些问题给出了相应的解决方法。     

A content-based goods image recommendation system

The information of e-commerce images varies and different users may focus on different contents of the same image for different purpose. So the research on recommendation by computers is becoming more and more important. But retrieval based only on keywords obviously falls short for massive numbers of resource images. In this paper, we focus on a recommendation system of goods images based on image content. Goods images have a relatively homogenous background and have a wide range of applications. The recommendation consists of three stages. First, the image is pre-processed by removing the background. Second, a weighted representation model is proposed to represent the image. The separated features are extracted and normalized, and then the weights of each feature are computed based on the samples browsed by the users. Third, a feature indexing scheme is put forward based on the proposed representation. A binary-tree is used for the indexing, and a binary-tree updating algorithm is also given. Finally, the recommended images are given by a features combination searching scheme. Experimental results on a real goods image database show that our algorithm can achieve high accuracy in recommending similar goods images with high speed.     

基于截图内容的图片垃圾邮件过滤系统

垃圾邮件制造者常常将文字嵌入到图像中,产生了大量的图片垃圾邮件.为解决这一问题,提出并实现了一个基于截图内容的图片垃圾邮件过滤方案.首先由用户从垃圾邮件中截取某一子域图片,每一截图对应一类垃圾图片,所有的截图构成一个自定义的垃圾图片“黑名单”.其次对读入的每一封图片邮件,其内置图片与“黑名单”中的图片进行图像匹配.最后若存在匹配项,则判定该邮件含有用户已指定的垃圾图片信息.将此图片垃圾邮件过滤方案应用于一个小型的邮件收发系统,使用3 534幅垃圾邮件图片进行实验,结果证明了该垃圾邮件过滤方案有效.     

一种新型图像压缩系统的设计

为打破传统的摄像机-采集卡-存储卡为一体的简单采集存储设计模式,实现模拟视频和数字视频双采集及数据压缩、高速传输的新模式,设计了一种以FPGA为控制核心、DSP为图像数据处理中心、IP核的生成与双SDRAM乒乓缓存协同工作为技巧、PCI卡高速传输为手段的图像压缩系统。DSP逻辑编码的改进使图像压缩比得到进一步提高。通过实际测试,图像的压缩比可达26:1;FPGA+DSP+PCI卡的综合使用使处理图像数据的速度提高至少50%,图像转存速率更是达到了38 MB/s。     

A content based image retrieval system for a biological specimen collection

Digital photography and decreasing cost of storing data in digital form has led to an explosion of large digital image repositories. Since the number of images in image databases can be large (millions in some cases) it is important to develop automated tools to search them. In this paper, we present a content based image retrieval system for a database of parasite specimen images. Unlike most content based image retrieval systems, where the database consists of objects that vary widely in shape and size, the objects in our database are fairly uniform. These objects are characterized by flexible body shapes, but with fairly rigid ends. We define such shapes to be FleBoRE (Flexible Body Rigid Extremities) objects, and present a shape model for this class of objects. We have defined similarity functions to compute the degree of likeness between two FleBoRE objects and developed automated methods to extract them from specimen images. The system has been tested with a collection of parasite images from the Harold W. Manter Laboratory for Parasitology. Empirical and expert-based evaluations show that query by shape approach is effective in retrieving specimens of the same class.     

A scene image classification technique for a ubiquitous visual surveillance system

Multimedia Tools and Applications - The concept of smart cities has quickly evolved to improve the quality of life and provide public safety. Smart cities mitigate harmful environmental impacts and...     

A comprehensive system for image scene classification

In recent years, image scene classification based on low/high-level features has been considered as one of the most important and challenging problems faced in image processing research. The high-level features based on semantic concepts present a more accurate and closer model to the human perception of the image scene content. This paper presents a new multi-stage approach for image scene classification based on high-level semantic features extracted from image content. In the first stage, the object boundaries and their labels that represent the content are extracted. For this purpose, a combined method of a fully convolutional deep network and a combined network of a two-class SVM-fuzzy and SVR are used. Topic modeling is used to represent the latent relationships between the objects. Hence in the second stage, a new combination of methods consisting of the bag of visual words, and supervised document neural autoregressive distribution estimator is used to extract the latent topics (topic modeling) in the image. Finally, classification based on Bayesian method is performed according to the extracted features of the deep network, objects labels and the latent topics in the image. The proposed method has been evaluated on three datasets: Scene15, UIUC Sports, and MIT-67 Indoor. The experimental results show that the proposed approach achieves average performance improvement of 12%, 11% and 14% in the accuracy of object detection, and 0.5%, 0.6% and 1.8% in the mean average precision criteria of the image scene classification, compared to the previous state-of-the-art methods on these three datasets.

     

A digital image system for atmospheric research

This paper describes the architecture of a medium scale digital image processing system developed as a research tool for analysis of meteorological data. The system is also being used for research on efficient image processing systems. Four qualitative performance measures for any image processor are introduced with specific application to the present machine. Preliminary results with noise reduction algorithms in satellite data are presented. Lastly, the versatility of the machine as a test bed for architectural studies of the computational structure of image processors with a microprogrammable control unit is discussed.     

A kernel system for iconic image processing

We present a proposal for the design of a kernel system for iconic image processing operations and construct a virtual machine for image processing. The data structures and typical operations in the field of digital image processing are discussed. Furthermore, we give a formal definition of the operations and data objects required and describe one way to implement them by using the generic features of Ada.     

A system organization for parallel image processing

One of the problems in the development of multiprocessor systems for image analysis is the selection and efficient utilization of an interconnection network between the multiple processing units. This paper proposes a system organization centered around a class of interconnection networks and a global bus. Control schemes are developed for realizing the intertask communication requirements typically encountered in the parallel formulation of problems for image analysis. These schemes are simple, distributed and efficient. The utility of this organization is demonstrated by evaluating the performance of two applications.