CRC-1 6快速编码及其应用

论述了具有并行反馈寄存器结构的CRC-16快速编码器,在以单片机为数据终端的系统中完成了CRC-16快速编码的全过程.     

一种基于MBE的快速基音搜索算法研究

多带激励声码器(MBE)是目前理想的语音编码方案之一，他的核心参数是基音周期，分析过程采用ABS方法，提高了语音参数提取的准确性，可在噪声环境中合成出自然度和可懂度很高的语音。针对其基音搜索算法计算量过大的缺点，首先提出了一种新颖的中心偏离函数计算法，该方法先对原始语音进行傅里叶变换得到原始语音谱，再针对各个基音候选值确定其相应于原始语音谱的予带划分，通过对比每个划分的中心偏离量，可以确定最佳基音周期；其次设计了一种简单有效的倍频消除算法，通过简单的循环计算，可以消除倍频现象；仿真结果表明，这两种方法的结合不仅大大降低了原算法的计算量，而且保持了他精度高的优点。     

Dynamic reconfiguration policies for reconfigurable coded-WDM PONs

This article studies the issues arising when reconfiguring coded-WDM networks to provide protection against eavesdropping. Although the ability to reconfigure coded-WDM PONs dynamically has been recognized as an effective means of improving the security of OCDMA networks, this article provides the first in-depth study of the tradeoffs involved in carrying out this reconfiguration process. The article commences by showing that the degree of confidentiality and the traffic loss are two important, but conflicting, objectives in the design of reconfiguration policies. The reconfiguration problem is then formulated as a Markovian decision process (MDP). The results obtained from MDP theory are applied to establish optimal reconfiguration policies for coded-WDM networks with various system parameters. Finally, the advantages of the optimal reconfiguration policies over a class of threshold-based policies are illustrated through simulation results.     

A new transform coder for gray scale images using MRT

The demand for high-speed transmission of best quality images over the internet has led to a strong need for the development of better algorithm for coding images. The transform coders are highly popular in encoding images. M-dimensional real transform (MRT) gives an alternate representation of a signal in the frequency domain which involves only real addition. In this paper a new transform coder based on 4×4 MRT is proposed and its performance is analyzed for all types of grayscale images.     

CRC—16的一种快速编码器的实现

本文从具有串行移位结构的循环检错编码器出发,通过分析,总结出了每次处理8bit的具有并行反馈移位寄存器结构的快速编码器。并计算出了联结矩阵,完成了两个用于软件编解码运算表,给出了软件编解码流程图。本文涉及的快选编码器已用于实际系统。     

基于混合架构的H.264/AVC视频编码器设计

提出了基于DSP FPGA混合平台的H.264/AVC编码器设计思路与实现方法.以DSP为主处理器,FPGA为协处理器实现算法的硬件加速,针对编码器中最复杂耗时的模块,设计相应的硬件加速引擎.并针对硬件加速引擎制定出便于控制和数据传输的软/硬件通信协议,实现了H.264/AVC D1编码器所需的实时性能.     

双音多频（DTMF）密码器的研究与实现

ＤＴＭＦ编码器以其误码率低、工作可靠而被广泛应用，特别是在无线电传输中更显示出它在调制、解解、发射、接收方面的突出优点性。文中介绍利用ＤＴＭＦ信号构成地密码器，对其电路进行分析论述，最后给出实现电路原理图。     

基于率失真优化的递进UTCQ编码

本文提出了一种基于UTCQ量化器的递进静态图像小波编码算法。一致网格编码量化(UTCQ)用于小波系数的量化并得到了非常好的量化效果。UTCQ超集索引值构成系数位平面,率失真优化按照率失真斜率递减的顺序从系数位平面选择编码系数位。最先编码的位具有最大的率失真斜率,每编码一位都会使失真减少最大。率失真斜率的计算仅仅是利用MQ自适应算术编码器的概率状态估计表而进行的查表过程。MQ算术编码器进一步压缩率失真优化选择的系数位。率失真门限方法的编码速度比搜索最大的率失真斜率更快。该算法有较快的编码速度以及好的压缩效果。     

Secure MQ coder: An efficient way to protect JPEG 2000 images in wireless multimedia sensor networks

This paper presents a secure MQ coder (SMQ) for efficient selective encryption of JPEG 2000 images. Being different from existing schemes where encryption overhead is proportional to the size of plain image, SMQ only selectively encrypts tiny and constant volume of data in JPEG 2000 coding regardless of image size. It is extremely fast and suitable for protecting JPEG 2000 images in wireless multimedia sensor networks (WMSNs). Theoretical analysis and experimental results show that SMQ can achieve a balance between security and efficiency, while keeping comparable compression performance and energy consumption with standard JPEG 2000 coding.     

飞控计算机数据模拟器的设计与实现

为了更好的检查飞控采集器的动态采集能力,设计并实现了一种便携式飞控计算机数据模拟器,具有体积小、重量轻、可靠性高、不需要外接电源等优点。首先说明了该模拟器的实现方案和系统组成,然后详细阐述了各个组成模块的工作原理,该模拟器已应用在实际的数据调试、检查以及故障排除工作中,能够提高工作效率,并且稳定性好。