一种基于Linux的MP3播放器设计

本文讨论了一种基于Linux的MP3播放器的设计。系统基于Linux操作系统,利用GNU开发工具进行软件开发,使用C99标准的C语言编写,利用开源的高质量MPEG音频解码器MAD对MP3文件进行解码生成PCM数据,用ALSA中的PCM接口处理PCM数据,最后将数字信号转化为模拟信号,实现MP3音频的播放。     

基于SOPC的mp3播放器设计

本论文主要从音频播放和SOPC技术的交叉点出发,提出了运用SOPC技术在Altera的CyelonⅡ EP2C35FPGA上构建mp3播放器的设计方案。本设计运用IP复用、软硬件协同、硬件加速等方法,结合实验平台资源特点,构建了基于NiosⅡ软核处理器的mp3播放系统。实现了MPEGⅠ layerⅢ音频解码的流畅播放。该系统具有体积小,设计灵活,开发周期短等优点。     

一种基于Linux的MP3播放器设计

本文讨论了一种基于Linux的MP3播放器的设计.系统基于Linux操作系统,利用GNU开发工具进行软件开发,使用C99标准的C语言编写,利用开源的高质量MPEG音频解码器MAD对MP3文件进行解码生成PCM数据,用ALSA中的PCM接口处理PCM数据,最后将数字信号转化为模拟信号,实现MP3音频的播放.     

高清集成解码包设置指南

播放高清视频需要用到众多的分离器、视频解码器、音频解码器,还少不了播放器,对于大多数用户来说,要把它们找到并安装到自己的系统中不是一件容易的事情,技术上也有一定的难度,可能还会出现兼容性的问题。为了方便大家欣赏高清,于是就出现了"终极解码"和"完美解码"这样的高清视频播放集成化软件包。用好这两个集成包,播放高清便不在话下。     

基于ARM嵌入式平台的音视频解码播放系统设计与实现

针对传统音视频解码播放系统产生的音频与视频不同步问题，设计了一种基于嵌入式平台的音视频解码播放系统。该系统充分利用嵌入式平台内部的硬核资源，采用开源的Mad函数库对音频ES数据流进行解码，在ALSA函数库和FIMC函数接口的支持下，将解码成功的音频帧和视频帧分别传送至音视频播放设备，以此实现音视频的解码与同步。利用性能测试的方法对系统的解码与同步进行验证，测试结果表明，该系统通过对音视频帧进行同步控制，可实现同步播放音频与视频，最终使音视频PTS数据之间的时间差值趋于稳定状态，有利于提升观众在视觉和听觉方面的感受。     

通用音频解码器验证系统设计与实现

设计并实现了一个基于FPGA的音频解码器验证系统.同传统的验证系统相比,系统不仅具有很强的通用性,还具有良好的可扩展性和强大的图形化显示功能,可以很方便地对各种音频解码器进行片上验证.该系统的实现缩短了音频解码器的片上验证周期,有助于研究人员提高工作效率,具有很大的实用价值.     

基于BREW平台的H.264解码器的实现

介绍了H.264解码器在BREW平台上的实现方法,重点讨论了代码移植、优化和ARM编译过程中遇到的各种问题和相应的处理方法.并根据无线网络误码率高、误码常常造成播放中断等问题,实现了一种H.264解码器端的误码处理机制,使得解码应用程序的稳定性大大提高.在LG C910手机(ARM 9处理器)上的测试结果表明,对于QCIF格式的视频,在同时实现视频解码、显示以及QCP格式(QUALCOMM PureVoice)音频解码、播放等功能的情况下,优化后的H.264解码器仍可以达到9帧/s左右的解码和播放速度,满足了移动终端上的实时处理需求.     

音视频流实时分离及同步播放系统设计与实现

通过音频与视频解码器和相关的音视频流方案实现上位机与下位机音视频流数据的编码解码及重新合成,并给出了音视频在播放过程中实现同步校正的方法,实现了在有高音质外放设备情况下的上下位机播放的准确同步。系统在Android平台上已获得实现,所使用的音视频实时分离及同步播放方法能成功实现智能终端视频播放和高音质外放音频播放的准确同步,并在上位机成功合成新的音视频文件。     

基于FPGA的视频解码芯片验证平台设计

随着视频编解码算法复杂度的增加,视频处理器设计的难度和成本也大幅度增加.针对视频解码器芯片的仿真和验证要求,文章提出了视频解码芯片的验证框架.基于VirtexE系列的FPGA芯片设计实现了视频解码器的验证平台.并对视频解码器的FPGA的验证问题进行了分析.     

H.264的FPGA解码器中去块效应滤波器设计

介绍了H．264的FPGA解码芯片系统中去块效应滤波系统模块的设计结构,分析了该系统设计原理。介绍了详细的FPGA去块效应模块实现方案,使得整个系统能够满足解码器实时显示的要求。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.