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1.
Continuing advances in digital image capture and storage are resulting in a proliferation of imagery and associated problems of information overload in image domains. In this work we present a framework that supports image management using an interactive approach that captures and reuses task-based contextual information. Our framework models the relationship between images and domain tasks they support by monitoring the interactive manipulation and annotation of task-relevant imagery. During image analysis, interactions are captured and a task context is dynamically constructed so that human expertise, proficiency and knowledge can be leveraged to support other users in carrying out similar domain tasks using case-based reasoning techniques. In this article we present our framework for capturing task context and describe how we have implemented the framework as two image retrieval applications in the geo-spatial and medical domains. We present an evaluation that tests the efficiency of our algorithms for retrieving image context information and the effectiveness of the framework for carrying out goal-directed image tasks.  相似文献   

2.
数字多媒体取证技术综述   总被引:5,自引:2,他引:3  
数字多媒体取证是信息安全一个刚刚兴起的研究领域,研究数字多媒体取证技术对确保多媒体数据的可靠性有着极其重要的意义。以数字图像取证为代表,从篡改检测、来源辨识、真实性鉴定、设备成分取证以及多媒体取证方法的可靠性等五个方面对现有数字多媒体取证技术进行综述,重点介绍了典型算法,并指出当前研究中存在的一些主要问题,给出本领域未来的研究方向。  相似文献   

3.
Multimedia information management and communications systems for medical applications have been undergoing design and development. The aim of these activities has been the development of distributed computer systems providing storage, processing, and communication services required by the medical community. One of the main critical issues of such systems is the handling of multimedia information (i.e., text, images, graphics, and voice) in a uniform way and the fast access to images through the network. We present the design architecture and concepts used in our multimedia database system, along with its performance evaluation. The evaluation focuses on the response times of a multimedia medical database server, as seen by remote workstations for various retrieval and image transfer requests. For this purpose, a queueing network model was developed and simulated. Communications between the workstations and the database server are governed by the client-server model using TCP/IP and appropriate application protocols on a 10 Mb/s Ethernet LAN  相似文献   

4.
伴随着多媒体采集和处理设备成本的不断降低,以及处理目标的不断复杂化,多媒体信息系统正朝着大规模数据分析和管理系统靠拢,因此如何有效支持实时分布式多媒体信息所需的实时采集、压缩、传输、处理、描述、反馈与存档,以及后期的浏览与检索,已经成为多媒体计算研究的重要问题。为了有效支持实时分布式多媒体信息的实时采集、传输、处理、描述、存档等的需要,在分析动态上下文环境下实时分布式多媒体系统对底层采集、压缩和传输以及信息的表达和存储的普遍需求的基础上,提出并实现了一个通用的实时分布式媒体信息处理框架,以便为实时分布多媒体系统提供基础服务支持。该框架包括软件平台和信息系统两部分。前者用于将逻辑功能与物理设备隔离开来,完成实时采集、压缩、传输和解压等功能;后者通过统一信息表达格式,将数据与特定的采集处理模块隔离开来,同时还提供了信息管理的功能,以便于用户后期检索。这两部分共同将多媒体系统所需要的实时采集、处理、压缩、描述、反馈与存档以及离线浏览与检索等服务融入一致、统一的框架中。基于该框架的会议系统的相关实验表明,该框架具有良好的开放性、可配置性和可扩展性。  相似文献   

5.
《Computer》2002,35(4):58-66
Developments in information retrieval technologies can make multimedia data as pervasive and important as textual sources in knowledge management systems. The authors suggest ways in which speech-based multimedia information retrieval technologies can evolve into full-fledged knowledge management systems  相似文献   

6.
数字化管理和一流的医疗设备是医院现代化的两个主要组成部分,通过计算机网络,PACS系统实现了各类医疗图像信息的集中管理和共享,HIS系统则把医院的事务管理和医疗业务进行信息化管理,计算机网络和数字化管理在医院中的作用显得日益重要。为加强网络管理,保障数字化、信息化管理的安全,本文在分析医院信息网络安全所面临问题的基础上,探讨了解决计算机病毒、信息系统崩溃、数据遗失等问题的措施。  相似文献   

7.
用于图象认证的数字水印技术   总被引:15,自引:1,他引:14       下载免费PDF全文
随着多媒体网络通讯技术的飞速发展 ,数字信息的安全维护问题日益突出 .目前 ,采用数字水印技术 (即脆弱性数字水印和半脆弱性数字水印 )进行数字图象的真实性、完整性认证已成为信息认证领域的研究热点 .为使国内广大科技人员能够较全面地了解数字水印图象认证技术的发展现状 ,给出了用于图象认证的数字水印系统的基本框架、性能要求及常见的攻击方法 ,介绍了现有的各种算法 ,分析和总结了各自的优缺点 ,并提出了下一步的研究方向 .  相似文献   

8.
For the first time in the field of medical imaging, harmonious use of Z-contrast imaging and digital image processing was developed as an analytical imaging tool and demonstrated in studying human and rabbit spermatozoa. The biological information generated is unique to the science of medical imaging. The versatility of its applications is wide as this advance in imaging technology can be applied to any area of medicine involving tissue analysis. Tissue analysis plays a vital role in both medical research and diagnostic patient care. Imaging in the Z-contrast mode of the scanning-transmission electron microscope affords biologists the capability to image tissue in its natural state such that heavy metal fixatives and stains are not used. The digitally processed Z-contrast image is not only devoid of artifacts caused by fluctuating mass-density, topography variations, and the addition of heavy metal contrast agents but also offers a biological blueprint of the atomic weight distribution in the tissue. The varying gray level intensities assigned to each pixel in the resulting image are specific to the average atomic weight differences inherent in the tissue. The advent of complementary Z-contrast imaging and digital image processing and their concomitant research possibilities offers areas of medical care and medical research an invaluable imaging tool.  相似文献   

9.
基于脆弱性数字水印的图象完整性验证研究   总被引:18,自引:1,他引:18       下载免费PDF全文
计算机网络技术的飞速发展与信息媒体的数字化 ,使得在网络环境中对数字产品实施有效的内容保护成为一个迫在眉睫的现实问题 .传统的数字签名技术只是用于对通信领域的信息传送进行篡改检测 ,而脆弱性数字水印技术则为网络环境下多媒体的内容保护提供了一个有效的解决方案 .与鲁棒性水印不同的是 ,脆弱性水印主要用于检测发生在多媒体数据中的篡改 ,并对其定位 .为了推动我国在此前沿领域研究工作的进一步深入 ,这里就当前脆弱性数字图象图象水印技术的基本特征、一般原理、研究现状、攻击方法及发展方向进行一个综述 .  相似文献   

10.
11.
Telemedicine has evolved rapidly in recent years to enable unprecedented access to digital medical data, such as with networked image distribution/sharing and online (distant) collaborative diagnosis, largely due to the advances in telecommunication and multimedia technologies. However, interactive collaboration systems which control editing of an object among multiple users are often limited to a simple “locking” mechanism based on a conventional client/server architecture, where only one user edits the object which is located in a specific server, while all other users become viewers. Such systems fail to provide the needs of a modern day telemedicine applications that demand simultaneous editing of the medical data distributed in diverse local sites. In this study, we introduce a novel system for telemedicine applications, with its application to an interactive segmentation of volumetric medical images. We innovate by proposing a collaborative mechanism with a scalable data sharing architecture which makes users interactively edit on a single shared image scattered in local sites, thus enabling collaborative editing for, e.g., collaborative diagnosis, teaching, and training. We demonstrate our collaborative telemedicine mechanism with a prototype image editing system developed and evaluated with a user case study. Our result suggests that the ability for collaborative editing in a telemedicine context can be of great benefit and hold promising potential for further research.  相似文献   

12.
Design of a multimedia object-oriented DBMS   总被引:1,自引:0,他引:1  
The emerging multimedia information (such as video, image, voice, graphics) services have imposed many new requirements and research considerations on the design of database management systems (DBMSs). Conventionally, a multimedia DBMS is designed by developing a multimedia presentation layer on top of a pre-existing object-oriented DBMS (which can be truly object-oriented or relational-based), such that the core of the DBMS was developed earlier independent of the design of the multimedia presentation layer. Due to the fact that multimedia capabilities are not actually embedded in the DBMSs, such systems tend to provide only a rather limited set of functionalities in multimedia and are not satisfactory in supporting multimedia applications. This paper describes some key features of a multimedia object-oriented DBMS that is currently being developed. In this system the DBMS is carefully redesigned to provide special multimedia capabilities, such that the mismatch between the DBMS and the multimedia application layer can be eliminated. In particular, this paper will focus on unique multimedia capabilities including multimedia object modeling, video data management, and distributed collaboration. This project was supported in part by Rome Laboratory, U.S. Air Force under the contract no. F30602-94-C-0090  相似文献   

13.
Knowledge management has become a challenge for almost all e-government applications where the efficient processing of large amounts of data is still a critical issue. In the last years, semantic techniques have been introduced to improve the full automatic digitalization process of documents, in order to facilitate the access to the information embedded in very large document repositories. In this paper, we present a novel model for multimedia digital documents aiming at improve effectiveness of digitalization activities within an information system supporting e-government organizations. At the best of our knowledge, the proposed model is one of the first attempts to give a single and unified characterization of multimedia documents managed by e-government applications, whereas semantic procedures and multimedia facilities are used for the transformation of unstructured documents into structured information. Furthermore, we define an architecture for the management of multimedia documents “life cycle”, which provides advanced functionalities for information extraction, semantic retrieval, indexing, storage, presentation, together with long-term preservation. Preliminary experiments concerning an e-health scenario are finally presented and discussed.  相似文献   

14.
Detection and recognition of textual information in an image or video sequence is important for many applications. The increased resolution and capabilities of digital cameras and faster mobile processing allow for the development of interesting systems. We present an application based on the capture of information presented at a slide-show presentation or at a poster session. We describe the development of a system to process the textual and graphical information in such presentations. The application integrates video and image processing, document layout understanding, optical character recognition (OCR), and pattern recognition. The digital imaging device captures slides/poster images, and the computing module preprocesses and annotates the content. Various problems related to metric rectification, key-frame extraction, text detection, enhancement, and system integration are addressed. The results are promising for applications such as a mobile text reader for the visually impaired. By using powerful text-processing algorithms, we can extend this framework to other applications, e.g., document and conference archiving, camera-based semantics extraction, and ontology creation.Received: 18 December 2003, Revised: 1 November 2004, Published online: 2 February 2005  相似文献   

15.
Information retrieval algorithms have changed the way we manage and use various data sources, such as images, music or multimedia collections. First, free text information of documents from varying sources became accessible in addition to structured data in databases, initially for exact search and then for more probabilistic models. Novel approaches enable content-based visual search of images using computerized image analysis making visual image content searchable without requiring high quality manual annotations. Other multimedia data followed such as video and music retrieval, sometimes based on techniques such as extracting objects and classifying genre. 3D (surface) objects and solid textures have also been produced in quickly increasing quantities, for example in medical tomographic imaging. For these two types of 3D information sources, systems have become available to characterize the objects or textures and search for similar visual content in large databases. With 3D moving sequences (i.e., 4D), in particular medical imaging, even higher-dimensional data have become available for analysis and retrieval and currently present many multimedia retrieval challenges. This article systematically reviews current techniques in various fields of 3D and 4D visual information retrieval and analyses the currently dominating application areas. The employed techniques are analysed and regrouped to highlight similarities and complementarities among them in order to guide the choice of optimal approaches for new 3D and 4D retrieval problems. Opportunities for future applications conclude the article. 3D or higher-dimensional visual information retrieval is expected to grow quickly in the coming years and in this respect this article can serve as a basis for designing new applications.  相似文献   

16.
Multi-modal medical image fusion, as a powerful tool for the clinical applications, has developed with the advent of various imaging modalities in medical imaging. The main motivation is to capture most relevant information from sources into a single output, which plays an important role in medical diagnosis. In this paper, a novel framework for medical image fusion based on framelet transform is proposed considering the characteristics of human visual system (HVS). The core idea behind the proposed framework is to decompose all source images by the framelet transform. Two different HVS inspired fusion rules are proposed for combining the low- and high-frequency coefficients respectively. The former is based on the visibility measure, and the latter is based on the texture information. Finally, the fused image is constructed by the inverse framelet transform with all composite coefficients. Experimental results highlight the expediency and suitability of the proposed framework. The efficiency of the proposed method is demonstrated by the different experiments on different multi-modal medical images. Further, the enhanced performance of the proposed framework is understood from the comparison with existing algorithms.  相似文献   

17.
实时动态信息发布系统正是在这种背景环境下诞生的一种新型的媒体发布应用系统。实时动态信息发布系统是一种通过数字化音、视频多媒体处理,通过网络实现远程多点分布式播放和集中管理控制的系统,播放的信息是实时动态系统;一个操作员可以集中建立、编辑和分配内容给网络环境中的数量庞大的显示终端,即实现一台服务器集中管理,向多个不同场所地点的显示终端发布实时动态的多媒体信息。  相似文献   

18.
Fusing medical images is a topic of interest in processing medical images. This is achieved to through fusing information from multimodality images for the purpose of increasing the clinical diagnosis accuracy. This fusion aims to improve the image quality and preserve the specific features. The methods of medical image fusion generally use knowledge in many different fields such as clinical medicine, computer vision, digital imaging, machine learning, pattern recognition to fuse different medical images. There are two main approaches in fusing image, including spatial domain approach and transform domain approachs. This paper proposes a new algorithm to fusion multimodal images. This algorithm is based on Entropy optimization and the Sobel operator. Wavelet transform is used to split the input images into components over the low and high frequency domains. Then, two fusion rules are used for obtaining the fusing images. The first rule, based on the Sobel operator, is used for high frequency components. The second rule, based on Entropy optimization by using Particle Swarm Optimization (PSO) algorithm, is used for low frequency components. Proposed algorithm is implemented on the images related to central nervous system diseases. The experimental results of the paper show that the proposed algorithm is better than some recent methods in term of brightness level, the contrast, the entropy, the gradient and visual information fidelity for fusion (VIFF), Feature Mutual Information (FMI) indices.  相似文献   

19.
With the augmentation in multimedia technology, demand for high-speed real-time image compression systems has also increased. JPEG 2000 still image compression standard is developed to accommodate such application requirements. Embedded block coding with optimal truncation (EBCOT) is an essential and computationally very demanding part of the compression process of JPEG 2000 image compression standard. Various applications, such as satellite imagery, medical imaging, digital cinema, and others, require high speed and performance EBCOT architecture. In JPEG 2000 standard, the context formation block of EBCOT tier-1 contains high complexity computation and also becomes the bottleneck in this system. In this paper, we propose a fast and efficient VLSI hardware architecture design of context formation for EBCOT tier-1. A high-speed parallel bit-plane coding (BPC) hardware architecture for the EBCOT module in JPEG 2000 is proposed and implemented. Experimental results show that our design outperforms well-known techniques with respect to the processing time. It can reach 70 % reduction when compared to bit plane sequential processing.  相似文献   

20.
An architecture for digital teaching of radiology targets the next generation of network based education in diagnostic imaging. We developed applications of this system in UCSF hospitals (San Francisco, USA). The networked digital teaching file for medical imaging presented here builds on the availability of existing clinical information infrastructure in hospitals, such as PACS and RIS, and the recent advances in open systems Internet technology. Such a digital teaching file possesses enormous potential to change the practice and landscape of medical imaging education. Countries throughout the world share the goal of improving health care productivity and quality. They must invest not only in clinical services, but also in effective training of a new generation of imaging specialists. A networked digital teaching file provides a cost effective tool for attaining this goal  相似文献   

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