红外线电路和TDCS电路安全保障解决方案

轴温探测(以下简称红外线)、TDCS电路已经成为铁路专用通信中与行车调度电路同等重要的电路,其质量及安全性直接影响到行车及行车的安全。下面结合陇海线天兰段、包兰线兰干段实际情况,谈谈如何能更好地解决红外线、TDCS电路的安全保障问题。1电路现状陇海线天兰段、包兰线兰干段红外线电路及部分TDCS音频电路只有一条路由,没有形成保护环,组网结构不合理,安全性差。以天兰段为例,如图1所示,天水至陇西间共计6个站,12条红外线电路,如果干线传输中某点大通道中断或某点检修作业时,就可能造成此点后面的所有站的红外线电路及TDCS音频电路中断,影响行车安全,也影响通信设备及通道检修、测试和故障处理。故障定责为     

基于比值的小波域数字音频盲水印算法

针对一些水印算法存在的不足提出一种基于离散小波变换的适于版权保护的数字音频盲水印算法。算法对能量的概念作了新的定义,对其设计原理和过程作了理论分析和实验验证。算法实现时先分帧音频并对各帧作n级离散小波变换,然后计算n级小波系数近似分量前后两部分的能量比值,并放大;再将放大后的比值修改为奇数或者偶数以嵌入水印,最后按与嵌入时相同的比例缩小第n级小波系数近似分量的前半部分并作小波逆变换,得到水印音频。算法根据n级小波系数近似分量前后两部分能量放大后比值的奇偶性提取水印,实现水印的盲检测,提取水印不需原始音频。采用混沌加密水印信号,缩放因子也是密钥,算法安全性得到双重保护。仿真结果证明了算法的鲁棒性和不可感知性。     

Improved Sinusoid Analysis and Post-Processing in Parametric Audio Coding

This paper proposed improvements to the low bit rate parametric audio coder with sinusoid model as its kernel. Firstly, we propose a new method to effectively order and select the perceptually most important sinusoids. The sinusoid which contributes most to the reduction of overall NMR is chosen. Combined with our improved parametric psychoacoustic model and advanced peak riddling techniques, the number of sinusoids required can be greatly reduced and the coding efficiency can be greatly enhanced. A lightweight version is also given to reduce the amount of computation with only little sacrifice of performance. Secondly, we propose two enhancement techniques for sinusoid synthesis: bandwidth enhancement and line enhancement. With little overhead, the effective bandwidth can be extended one more octave ; the timbre tends to sound much brighter, thicker and more beautiful.     

远程多媒体监控技术的研究

论述了远程多媒体监控系统构建和软件设计技术，提出了解决网上视频和音频传输的技术方法和远程多媒体监控系统的解决方案，并给出了视频传输软件的实现例程。     

Audio Video Compression Stream Synthesis and Implementation

Multiplex of digital streams is one of the key technologies in audio-video communication, and determines audio-video quality. A design scheme for an MPEG2 compliant digital television system including audio-video encoding and multiplexing was implemented. The principles and elements of system layer stream synthesis were analyzed. The key technologies of video and audio PES packetization were discussed, such as stream structure,scheduling matching, audio-video synchronization, data flow and buffering. DSP and FPGA are combined to construct header information and packet structure. The substitution of traditional RAM or PLD results in high operational efficiency and saves memory space. A scheduling algorithm was introduced for PES coding, using the monitor information of PES buffers. DTS is generated by multiplexer to guarantee synchronization. The system is not only simple but also stable, and maintains synchronization constraints of the standard. It supports both analogy and digital audio-video source input, and provides real-time MPEG2 compliant TS/PS output. It has perfect performance and meets the national broadcasting requirements.     

一种可补偿的新型架构音乐律动氛围灯控制方法

文章设计一种可补偿的新型架构音乐律动氛围灯控制方法,该方案包含THU车机及屏幕、BCM车辆车身控制单元、主节点氛围灯、从节点氛围灯、功放,具有解码与传递信号时效短、律动与音乐节拍同步性好、律动效果丰富等优点。     

基于DirectShow的音/视频传输系统设计与实现

在基于卫星通信的IP网络上,采用DirectShow架构,设计音频与视频数据的采集、编码,网络传输、解码及回放的解决方案,并用Vc++编程实现.为远程故障诊断、远程技术支援及远程视频监控等系统,提供通过语音与视频进行实时交流的功能.     

蓝牙高质量音频传输的两种实现方式及其应用

介绍在蓝牙无线通讯环境下实现高质量音频传输发送端的两种不同的方式,分析它们各自的适用场景以及优缺点,并将这两种方式推广到蓝牙视频传输应用.     

蓝牙耳机系统及其实现

介绍蓝牙及其协议栈体系结构;讨论了蓝牙耳机的基本概念及其应用模型,最后详细阐述了该蓝牙耳机系统的设计和具体实现.