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1.
Ninomiya  Y. 《Spectrum, IEEE》1995,32(4):54-57
Japan is the only country, so far, to be actually broadcasting high-definition television services. MUSE (multiple sub-Nyquist sampling encoding) is the basis for systems applying bandwidth compression to the transmission of both analog and digital signals. It encodes a signal of 1125 lines and 60 fields per second, a high-definition television (HDTV) signal into an 8-Hz bandwidth. Experimental MUSE broadcasts started in 1990 and have continued ever since. Meanwhile, work has been in progress in areas other than MUSE. Enhanced-definition television, a terrestrial system, is entering its second generation. Integrated digital broadcasting looks to spin many services into a single digital thread for transmission over a single channel. Digital sound broadcasting and hierarchical television transmission will also come in for consideration. The MUSE system depends on digital technology for signal processing, but the HDTV signal that is broadcast is analog, the outcome of frequency modulation  相似文献   

2.
This standard for digital high-definition television has been submitted to the Federal Communications Commission for its approval. Based as it is on the MPEG-2 video compression and transport protocol, multiple transmission formats, Dolby AC-3 digital audio, and vestigial sideband digital modulation, this HDTV system will supply the home with superb images and spectacular sound while also, as part of the National Information Infrastructure (NII), relaying digital data. An HDTV system employing multiple transmission formats, digital compression, packetization, and modulation techniques is a marked advance over current world television standards such as NTSC, PAL, or SECAM  相似文献   

3.
The H.264/MPEG4 advanced video coding standard and its applications   总被引:6,自引:0,他引:6  
H.264/MPEG4-AVC is the latest video coding standard of the ITU-T video coding experts group (VCEG) and the ISO/IEC moving picture experts group (MPEG). H.264/MPEG4-AVC has recently become the most widely accepted video coding standard since the deployment of MPEG2 at the dawn of digital television, and it may soon overtake MPEG2 in common use. It covers all common video applications ranging from mobile services and videoconferencing to IPTV, HDTV, and HD video storage. This article discusses the technology behind the new H.264/MPEG4-AVC standard, focusing on the main distinct features of its core coding technology and its first set of extensions, known as the fidelity range extensions (FRExt). In addition, this article also discusses the current status of adoption and deployment of the new standard in various application areas.  相似文献   

4.
Broadcast television in the United States has remained essentially unchanged in the last 50 years except for the addition of color and stereo sound. Today, personal computers are meeting the need for random access of high-resolution images and CD-quality audio. Furthermore, advances in digital video compression and digital communication technology have cleared the way toward offering high-resolution video and audio services to consumers using traditional analog communications channels. In 1987, the US Federal Communications Commission (FCC) chartered an advisory committee to recommend an advanced television system for the United States. From 1990 to 1992, the Advanced Television Test Center (ATTC) tested four all-digital systems, one analog high-definition television (HDTV) system, and one enhancement NTSC system using broadcast and cable television environment simulators. The formation of the HDTV Grand Alliance in May 1993 resulted from the withdrawal of the only analog HDN system from the competition and a stalemate between the other four all-digital systems. The HDTV Grand Alliance system is composed of the best components from previously competing digital systems demonstrated to the FCC. The Moving Pictures Experts Group (MPEG-2) syntax is used with novel encoding techniques to deliver a set of video scanning formats for a variety of applications. This article describes the important features and concepts embodied in the HDTV Grand Alliance system  相似文献   

5.
Packet video     
Pearson  D. 《IEE Review》1990,36(8):315-318
The 1990s will see a large increase in the use of video for many purposes, made possible through the use of new optical storage and transmission methods, as well as radio and satellite communication. HDTV, new broadcast services and 64 kbit/s ISDN video are all at an advanced stage of development. Digital methods of transmission and storage feature prominently in future scenarios of video usage. To avoid long delays in transmission, packet video techniques for storage of high-quality material on optical discs are being considered. Coded video signals can be transmitted in packet form at variable bit rate. The author discusses the principles of packet video. Packet loss, queueing delay and layered coding are discussed. The future developments are also discussed  相似文献   

6.
We introduce a high‐definition three‐dimensional television (3DTV) broadcasting system that is fully compatible with the existing transmission system of high‐definition television (HDTV). Specifically, we developed high‐definition 3DTV broadcasting subsystems including a 3DTV camera, 3DTV video multiplexer and demultiplexer, 3DTV receiver, and 3DTV outdoor broadcast van. To verify the developed subsystems, we performed experimental services of 3DTV broadcasting during the 2002 FIFA World Cup Korea/Japan.. According to our subjective evaluation test, 88% of 273 viewers rated the perceived depth of 3DTV as “Good,” and 36% of the viewers preferred 3DTV to other digital broadcasting services.  相似文献   

7.
Hierarchical coding of digital television   总被引:1,自引:0,他引:1  
If the same digital television signal is used for multiple resolutions, bit rates, or transmission and storage mechanisms, then hierarchical coding offers several advantages. The FCC has decided to adopt the "main profile" of MPEG-2 for the video representation of the signal that will be used in the North American terrestrial broadcasting of HDTV. The article examines the tradeoffs of using hierarchical coding and provides an overview of possible applications and existing techniques, with emphasis on the scaleable profiles of MPEG-2, in particular the technique of spatial domain scalability  相似文献   

8.
Applications of the digital signal processing of video signals in broadcasting, communication, and consumer electronics are reviewed. These include: digital encoding systems, digital video effect equipment, and the television standards converter for broadcasting; videoconferencing and video telephone equipment; and TV receivers, including those for extended definition and high-definition television (EDTV and HDTV). Performance requirements for video signal processing (VSP) are discussed, and an example of a video signal processor comprising a parallel processor system composed of multiple VSP modules is examined. Future trends in VSP are predicted  相似文献   

9.
A video codec LSI for high-definition television (HDTV) systems has been developed. By using a time-compressed integration encoding technique, it converts a 20.0-MHz bandwidth luminance signal and two 5.0-MHz chrominance signals into a compressed image signal at 48.6-MHz sampling frequency. It is useful in many HDTV application systems, such as 400-Mb/s digital transmission system, a video disk player system, or an analog transmission system. Over 288000 elements, including a 52-kb one-transistor DRAM (dynamic random access memory) line memory specially developed for this LSI, were integrated on a 12.16×12.10-mm2 chip. A standard cell layout method and a 1.2-μm CMOS logic LSI process were used  相似文献   

10.
Two high-definition television (HDTV) communication systems created for broadband communication networks are discussed. Nationwide HDTV transmission and distribution services and HDTV subscriber distribution services are examined. A network architecture for high-quality HDTV transmission is described. The transmission bit rates of HDTV services, which are the basic factors in constructing the network frame, are considered. Two HDTV coding algorithms, subband discrete cosine transform (DCT) and subband differential pulse-code modulation (DPCM) are described, and their coding bit rates discussed. A synchronous-digital-hierarchy-based synchronous transfer mode network design suitable for the transmission of HDTV signals in broadband communication networks are described  相似文献   

11.
12.
数字高清电视转播车作为移动式演播室系统在广电行业已经广泛使用,以12信道数字高清电视转播车为例,介绍了高清电视转播车视频系统构成,阐述了系统的设计原则以及视频系统、PFU微波传送设备、同步系统的选型和配置、应急方案等。  相似文献   

13.
A fiber-optic high-definition television (HDTV) distribution system is discussed, which economically distributes HDTV signals to customers at a bit rate of about 100 Mb/s. The subscriber network is formed in a star topology to facilitate bidirectional connection. The distribution system uses digital video transmission at 1.3 μm wavelength using single-mode fiber. The video channel selection is made by an optical video selector. The optical selector consists of laser diode optical switch modules, which have a gain in the `ON' state and two-input, two-output 3 dB couplers. The authors describe the bit error rate characteristics of a signal-mode fiber digital distribution system using a four-input, one-output optical selector  相似文献   

14.
This paper describes the architecture, functionality, and design of NX-2700, a digital television and media processor chip from Philips Semiconductors. The NX-2700 is the second generation of an architectural family of programmable multimedia processors targeted at the digital television (DTV) markets, including the United States Advanced Television Systems Committee (ATSC) DTV-standard-based applications. The chip not only supports all of the 18 ATSC formats from standard-definition to wide-angle, high-definition video, but has also the power to handle high-definition television (HDTV) video and audio source decoding (high-level MPEG-5 AC-3 and ProLogic audio, closed captioning, etc.) as well as the flexibility to process advanced interactive services. NX-2700 is a programmable processor with a very powerful, general-purpose very long instruction word (VLIW) central processing unit (CPU) core that implements many nontrivial multimedia algorithms, coordinates all on-chip activities, and runs a small real-time operating system. The CPU core, aided by an array of peripheral devices (multimedia coprocessors and input-output units) and high-performance buses, facilitates concurrent processing of audio, video, graphics, and communication-data  相似文献   

15.
Important advances in digital signal processing for HDTV have occurred in Asia. This article outlines these advances, including trends in standard resolution television (STV) and progress in superhigh definition (SHD) imaging. Video coding, video recording, SHD image processing, and digital satellite broadcasting are covered, and trends in digital satellite TV and the challenges facing successful implementation of the technology are presented, as well as future research and development targets for HDTV  相似文献   

16.
The packet-oriented transport approach used in the advanced digital television (ADTV) system for terrestrial HDTV broadcast is described. ADTV achieves robust HDTV delivery on terrestrial simulcast channels via MPEG video compression, prioritization of MPEG data, and `cell-relay' type packet transport in conjunction with a two-tier physical transmission scheme. General design issues relevant to the development of the proposed transport protocol are discussed. ADTV's prioritization algorithm for partitioning MPEG-encoded video into high-priority (HP) and standard-priority (SP) bit streams is outlined. The data transport format supporting these prioritized compressed video bit streams is described. The three principal sublayers of the ADTV transport protocol are discussed in terms of specific functions, impact of system performance, and hardware implementation factors. A proof-of-concept simulation model that incorporates transport encoding and decoding functionality is outlined, and performance evaluation results are given for illustrative transmission scenarios  相似文献   

17.
The characteristics of digital high-definition television (HDTV) and its advantages over analog and hybrid systems are described. The issues to be addressed in using digital transmission in the terrestrial broadcast environment are examined. Four proposed digital HDTV systems are discussed, and their similarities and differences are highlighted. Key techniques are the use of complex compression coding and motion compensation algorithms  相似文献   

18.
随着信息技术的快速发展,数字电视服务已被广泛认识。数字电视广播平台可以开展更多吸引人的服务,比如高清晰度电视、互动电视、Internet介入等。论文介绍了当今形势下,在数字电视领域中条件接收系统所受到的基于密码算法和基于控制字破解等几方面的主流攻击手段,以及几种用于确保条件接收系统安全的应对思路。  相似文献   

19.
本文先说明图象(image)与电视(video)的涵义和区别,多种业务综合(integratedservices)与多种信息结合(multimedia)的涵义和区别,有线电视(CATV)与交互电视(interactive)的涵义和区别,个人通信网(PCN)与屋内通信网(CPN)的涵义和区别。然后叙述数字图象与电视压缩编码(Video (?)mpression)的原理和发展,以及数字高清晰电视(HDTV)在通信、广播的应用和发展。  相似文献   

20.
本文介绍了一种高清晰度电视(HDTV)信号的数字传输用高效编码方法。由于HDTV信号的带宽宽,所以存在两个主要问题:一是HDTV信号的随机噪声比传统电视信号的大,因而导致编码的效率下降;二是需要很高的取样频率。这样,就限制了编码算法的硬件实现。因此,本文提出两种技术来解决这些问题:第一是时空自适应滤波器,用它可降低随机噪声并改善编码效率;第二是具有自适应内场/帧间预测的外插和内插编码算法,这种算法消除了因高的取样频率引起的问题并保证了高效编码性能。  相似文献   

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