电影电视照明技术发展动向

电影电视照明技术发展动向李旋宗中央电视台技术制作中心主任随着现代科学技术飞速发展，在影视技术领域由于微电子技术、计算机技术和数字技术的广泛应用，技术设备已进入数字化时代。新的技术设备使用极大丰富了影视创作手段，大大提高了影视作品的技术质量和艺术效果。...     

从活动图像记录媒介的创新看电视设备的发展

在传统摄录像记录媒体中,录像磁带一直是记录 电视信号的主要手段。进入20世纪90年代中后期, 随着数字技术应用领域的不断扩展,以及计算机的普 及和网络技术的进步,新一代的数字化摄录设备对 图、文、声、像等海量信息的数字化处理,需要高密度     

家用摄录像一体机

<正> 现在正在使用或即将要投入使用的摄录像一体机有:(1)高清晰度数字电视广播用于节目摄制的高清晰度摄录像一体机,其清晰度一般在1000线以上,售价一般在50～100万元左右;(2)模拟电视广播用于节目摄制的广播级别的摄录像一体机,其清晰度一般在700线以上,售价一般在20万元左右;(3)用于各业务部门摄制节目的业务级的摄录像一体机(如电教、公、检、法、海关等单位和部门),其清晰度一般在600线以上,售价一般在10万元左右;(4)专门用于普通家庭摄制生活节目的家用摄录像一体机,其清晰度分三个档次:①大于或等于230线的普通模拟摄录像一体机。②大于或等于400线的高带模拟摄录像一体机。③大于或等于500线的DV数码摄录像一体机。其售价在1500～20000元左右。本文仅介绍家用摄录像一体机。 模拟摄录像一体机 虽然模拟摄录像一体机由于清晰度较低(普通机为230线,高带机为400线左右),信噪比较低(42～45dB),特别是因其固有的缺陷造成的每制作一代,信号     

江西电视台突发事件电视报道技术保障体系在抗洪救灾新闻宣传中发挥重要作用

江西电视台突发事件电视报道技术保障体系由领导小组、应急技术分队及应急技术设备组成。领导小组由分管台长担任组长，技术规划部、播出部和制作部的主任担任副组长。领导小组负责摄、录、编、传输和播出各环节人员的安排和设备的调拨，负责与节目口的工作协调。应急技术分队主要由卫星车、卫星收录、演播室、非编网、播出的技术人员组成，     

数字摄录一体机的新进展

简要叙述了ＤＶ数字摄录机的记录格式，主要性能及优点，并重点就是近一年来取得的主要进展如摄录机的数字接口、无带数字摄录机以及摄录像与照相一体机进行了介绍。     

平凡诚信的监理者——记重庆鼎信建设监理有限公司

重庆鼎信建设监理有限公司成立于2001年12月，注册资金1000万元人民币。是获得国家信息产业部甲级通信建设监理资质、取得ISO质量体系认证的监理企业。公司拥有雄厚的专业技术力量，先进而精良的技术设备以及丰富的监理经验，主要为各电信运营商提供各类通信工程建设监理和技术咨询服务。     

加强管理提高设备利用率

改革开放以来，随着事业发展，中央电视台的技术设备更新很快，每年都购置相当数量的技术设备。目前技术设备已占全台固定资产的70％左右，为电视媒体的宣传工作提供了必要的物质条件。由于技术设备价格昂贵，是电视节目成本核算的主要因素，因此，加强对技术设备的科学管理，提高技术设备的利用率，成为降低节目制作成本的重要环节。     

改制摄像机电源

近年来，许多电视台、站及电教部门，先后购进了一批摄录像器材，它们大都是日本的索尼、日立、松下和胜利公司的产品，因为购进的时间、公司不同，所以摄录像器材本身携带的电源不同，配备的电池型号则不同，每次出外景时，就需带几种不同型号的充电机，增加负担，很不方便。     

5G通信在城市轨道交通的运用

当人们还在感叹4G通信技术的便捷时,5G通信技术已经悄然而至.5G通信技术设备可以应用在生活中的方方面面,不但可以用在个体的手机及笔记本电脑上,还可以应用在智能交通系统上.与4G通信技术设备相比,5G通信技术设备不仅仅能够为旅客提供便捷,与此同时还能够提高城市地铁的安全性,使旅客的生命安全获得保障.本文将简单分析城市轨...     

数字化监控系统在广播设备管理中的应用

通信、计算机、自动化技术的发展，带动了监控技术的发展与应用，并逐渐演变成集中监控系统。近年来网络技术的发展、信息的交换传输、嵌入式技术、电源集成等先进现代化技术设备为集中监控系统、远程管理、设备网络化的建立和应用又打下了基础，为科学化地管理提供了可能。     

Digital video recording

Through mutual technology transfer between consumer and professional video recorders, the last 20 years has witnessed a rapid evolution from analog to digital recording. Each new digital videotape recorder (VTR) uses different channel coding. This implies that improving the recording density involves the development of new channel-coding schemes together with evolutionary magnetic tapes and heads. As a result, professional digital VTR's offer the best features for video recording. This paper reviews state-of-the-art magnetic recording devices, signal processing techniques for digital recording. It also describes the specifications for home-use digital recorders for current television systems, and discusses disk recording technology in the future     

Low-power wireless video systems

This article presents the design principles for implementing low-power wireless video systems through the use of two examples, a single-chip digital video camera and a wireless video-on-demand system. The discussion focuses on the architectural and circuit techniques developed specifically for silicon integration of high-performance low-power wireless video systems. The proposed single-chip digital camera incorporates a parallel architecture to perform MPEG-2 encoding in real time, while the video-on-demand system employs an error-resilient compression algorithm to guard against the transmission errors often encountered in wireless communication. Both wireless video systems, one for encoding and the other for decoding, dissipate only tens of milliwatts of power, achieving a power reduction two orders of magnitude below standard solutions     

面向Android的音视频传输策略的研究

谷歌发布的Android操作系统为应用层开发者提供了MediaRecoder对象和MediaPlayer对象用于音视频应用的开发,但它们主要针对音视频的摄录和播放需求,无法满足开发者基于摄像头和麦克等硬件设备的实时音视频流化传输需求.因此,在对Android操作系统进行深入研究的基础上,提出了一种高效灵活的音视频传输策略,然后依据此策略设计了一个第三方音视频流化传输组件libavstream.最后基于libavstream设计了一个音视频直播应用BLife,验证了本文所提出策略的可用性和有效性.     

“两客一危”3G无线视频监控车载系统

全面提升"两客一危"车辆的行驶安全和客运服务质量,利用加载了3G模块的无线视频监控车载终端系统,实现对车辆行驶记录、视频取证、远程视频监控的管理。车内安装摄像机、拾音器、紧急报警按钮和车载信息显示屏,分别作为视频图像、音频数据、紧急报警信息、GPS等信息的采集设备,采集后的信息经过车载硬盘录像机的处理之后,由车载硬盘录像机自带的3G无线通信模块发送给监控中心。     

Aerial video surveillance and exploitation

There is growing interest in performing aerial surveillance using video cameras. Compared to traditional framing cameras, video cameras provide the capability to observe ongoing activity within a scene and to automatically control the camera to track the activity. However, the high data rates and relatively small field of view of video cameras present new technical challenges that must be overcome before such cameras can be widely used. In this paper, we present a framework and details of the key components for real-time, automatic exploitation of aerial video for surveillance applications. The framework involves separating an aerial video into the natural components corresponding to the scene. Three major components of the scene are the static background geometry, moving objects, and appearance of the static and dynamic components of the scene. In order to delineate videos into these scene components, we have developed real time, image-processing techniques for 2-D/3-D frame-to-frame alignment, change detection, camera control, and tracking of independently moving objects in cluttered scenes. The geo-location of video and tracked objects is estimated by registration of the video to controlled reference imagery, elevation maps, and site models. Finally static, dynamic and reprojected mosaics may be constructed for compression, enhanced visualization, and mapping applications     

Temporal video segmentation: A survey

Temporal video segmentation is the first step towards automatic annotation of digital video for browsing and retrieval. This article gives an overview of existing techniques for video segmentation that operate on both uncompressed and compressed video stream. The performance, relative merits and limitations of each of the approaches are comprehensively discussed and contrasted. The gradual development of the techniques and how the uncompressed domain methods were tailored and applied into compressed domain are considered. In addition to the algorithms for shot boundaries detection, the related topic of camera operation recognition is also reviewed.     

Point-sampled 3D video of real-world scenes

This paper presents a point-sampled approach for capturing 3D video footage and subsequent re-rendering of real-world scenes. The acquisition system is composed of multiple sparsely placed 3D video bricks. The bricks contain a low-cost projector, two grayscale cameras and a high-resolution color camera. To improve on depth calculation we rely on structured light patterns. Texture images and pattern-augmented views of the scene are acquired simultaneously by time multiplexed projections of complementary patterns and synchronized camera exposures. High-resolution depth maps are extracted using depth-from-stereo algorithms performed on the acquired pattern images. The surface samples corresponding to the depth values are merged into a view-independent, point-based 3D data structure. This representation allows for efficient post-processing algorithms and leads to a high resulting rendering quality using enhanced probabilistic EWA volume splatting. In this paper, we focus on the 3D video acquisition system and necessary image and video processing techniques.     

Novel video stabilization for real-time optical character recognition applications

This paper presents a novel video stabilization algorithm for real-time optical character recognition (OCR) applications. The proposed method generates output frames in order to stabilize the position of a target word that will be recognized by the OCR application. Unlike in conventional algorithms, in the proposed algorithm, a causal low pass filter is not applied to the trajectory of the target word for reducing the high frequency component of camera motion. The proposed algorithm directly calculates the stable position of the word using two forces: the force used to pull the target word to the center of an output frame and a back force used to return the center of an output frame to the center of an input frame. Hence, the proposed algorithm significantly minimizes the time take to respond to sudden camera movement. Although the proposed method may not outperform state-of-the-art video stabilization in terms of video stability, the proposed technique is much more appropriate for real-time OCR applications than the conventional techniques in terms of accuracy, computational cost, processing delay, and the time taken to respond to sudden camera movement. Simulation results prove the superiority of the proposed method over conventional techniques for real-time OCR applications.     

高速摄像机观察中高压陶瓷电容材料的击穿现象

使用专业高速摄像机,在线观察研究了中高压陶瓷电容材料在电场作用下被击穿破坏过程。结果表明,中高压陶瓷电容材料的击穿通常发生在0.17～0.25 ms。在电场强度逐渐增强的过程中,还可以观察到陶瓷样品的放电、气体放出以及陶瓷介质的燃烧等现象。击穿前出现的放电频率越高,材料的击穿电场强度越低,而气孔率的减小有助于材料击穿电场强度的提高。     

Compressed video processing for cut detection

One of the challenging problems in video databases is the organisation of video information. Segmenting a video into a number of clips and characterising each clip has been suggested as one mechanism for organising video information. This approach requires a suitable method to automatically locate cut points (boundaries between consecutive camera shots in a video). Several existing techniques solve this problem using uncompressed video. Since video is increasingly being captured, moved, and stored in compressed form, there is a need for detecting shot boundaries directly in compressed video. The authors address this issue and show certain feature extraction steps in MPEG compressed video that allow the implementation of most of the existing cut detection methods developed for uncompressed video for MPEG video stream. They also examine the performance of three tests for cut detection by viewing the problem of cut detection as a statistical hypothesis testing problem. As the experimental results indicate, the statistical hypothesis testing approach permits fast and accurate detection of video cuts