期刊文献+
共找到270篇文章
< 1 2 14 >
每页显示 20 50 100
System-on-a-Chip (SoC) Based Hardware Acceleration for Video Codec
1
作者 Xinwei Niu Jeffrey Fan 《Optics and Photonics Journal》 2013年第2期112-117,共6页
Nowadays, from home monitoring to large airport security, a lot of digital video surveillance systems have been used. Digital surveillance system usually requires streaming video processing abilities. As an advanced v... Nowadays, from home monitoring to large airport security, a lot of digital video surveillance systems have been used. Digital surveillance system usually requires streaming video processing abilities. As an advanced video coding method, H.264 is introduced to reduce the large video data dramatically (usually by 70X or more). However, computational overhead occurs when coding and decoding H.264 video. In this paper, a System-on-a-Chip (SoC) based hardware acceleration solution for video codec is proposed, which can also be used for other software applications. The characteristics of the video codec are analyzed by using the profiling tool. The Hadamard function, which is the bottleneck of H.264, is identified not only by execution time but also another two attributes, such as cycle per loop and loop round. The Co-processor approach is applied to accelerate the Hadamard function by transforming it to hardware. Performance improvement, resource costs and energy consumption are compared and analyzed. Experimental results indicate that 76.5% energy deduction and 8.09X speedup can be reached after balancing these three key factors. 展开更多
关键词 SOC Software PROFILING HARDWARE ACCELERATION Video codec
在线阅读 下载PDF
基于X⁃codec探究不同特征下的语音生成效果
2
作者 何应来 《信息记录材料》 2025年第5期160-163,244,共5页
为探究X⁃codec对大语言模型音频生成性能的影响,本研究基于LibriSpeech数据集分析语料特征(时长、音色)对基于X⁃codec的大语言模型(large language model,LLM)在音频生成任务中的表现。相似性目标(similarity objective,Sim⁃O)得分和全... 为探究X⁃codec对大语言模型音频生成性能的影响,本研究基于LibriSpeech数据集分析语料特征(时长、音色)对基于X⁃codec的大语言模型(large language model,LLM)在音频生成任务中的表现。相似性目标(similarity objective,Sim⁃O)得分和全体平均意见得分(user test mean opinion score,UTMOS)指标测定结果表明:当语料时长超过10 s(即长语料)且音色为男声时,Sim⁃O得分和UTMOS在算术平均数上均显著高于相应特征分类中的其他组,同时在标准差上均显著低于相应特征分类中的其他组。因此,男声的长语料更有可能使应用了X⁃codec的LLM性能达到最佳状态。本研究结果可为优化音频编解码器设计提供理论支持。 展开更多
关键词 X⁃codec 大语言模型 相似性目标 全体平均意见得分
在线阅读 下载PDF
Quantum color image encryption: Dual scrambling scheme based on DNA codec and quantum Arnold transform
3
作者 Tao Cheng Run-Sheng Zhao +2 位作者 Shuang Wang Kehan Wang Hong-Yang Ma 《Chinese Physics B》 2025年第1期235-244,共10页
In the field of Internet, an image is of great significance to information transmission. Meanwhile, how to ensure and improve its security has become the focus of international research. We combine DNA codec with quan... In the field of Internet, an image is of great significance to information transmission. Meanwhile, how to ensure and improve its security has become the focus of international research. We combine DNA codec with quantum Arnold transform(QAr T) to propose a new double encryption algorithm for quantum color images to improve the security and robustness of image encryption. First, we utilize the biological characteristics of DNA codecs to perform encoding and decoding operations on pixel color information in quantum color images, and achieve pixel-level diffusion. Second, we use QAr T to scramble the position information of quantum images and use the operated image as the key matrix for quantum XOR operations. All quantum operations in this paper are reversible, so the decryption operation of the ciphertext image can be realized by the reverse operation of the encryption process. We conduct simulation experiments on encryption and decryption using three color images of “Monkey”, “Flower”, and “House”. The experimental results show that the peak value and correlation of the encrypted images on the histogram have good similarity, and the average normalized pixel change rate(NPCR) of RGB three-channel is 99.61%, the average uniform average change intensity(UACI) is 33.41%,and the average information entropy is about 7.9992. In addition, the robustness of the proposed algorithm is verified by the simulation of noise interference in the actual scenario. 展开更多
关键词 DNA codec quantum Arnold transform quantum image encryption algorithm
原文传递
Design and Implementation of Programmable RS Codec Module in Satellite Communication Modem 被引量:3
4
作者 邹翊 王华 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期350-354,共5页
In the study and implementation of a programmable RS codec module in satellite communication modem, FPGA is used as the kernel in the implementation, while some ASICs are used as necessary assistant measures. The modu... In the study and implementation of a programmable RS codec module in satellite communication modem, FPGA is used as the kernel in the implementation, while some ASICs are used as necessary assistant measures. The module includes the RS codec unit, the interleaver and deinterleaver unit, the scrambler and descrambler unit and the frame synchronization unit. The module is realized successfully and it can be programmed on-line to meet the requirements of IESS 308/309/310 including many specifications about different service types and data rates. With the implementation combining FPGA with ASICs, size of the circuit is much reduced, its flexibility dramatically increased, and its stability further strengthened. Furthermore, the module is based on the software radio concept and can be easily integrated into the whole satellite communication modem. 展开更多
关键词 RS codec INTERLEAVER FPGA software radio
在线阅读 下载PDF
TLV320AIC23 CODEC与DSP的接口应用 被引量:4
5
作者 计丹 黄光明 雷环利 《电声技术》 北大核心 2002年第10期39-42,共4页
关键词 TLV320AIC23 codec DSP 接口 数字编解码器 数字信号处理器 MPEG
在线阅读 下载PDF
Windows环境下用软件CODEC实现数字视频实时通信 被引量:1
6
作者 陈宁 谈大龙 王庆鹏 《计算机工程》 CAS CSCD 北大核心 2001年第9期144-146,共3页
讨论了Windows环境下利用软件编解码器实现视频压缩的方法和技巧,结合视频捕获和视频传输,以网络环境下机器人遥操作的实际应用为背景,给出了数字视频实时通信的编程实例。
关键词 软件编解码 数字视频实时通信 WINDOWS codec 视频捕获 视频传输
在线阅读 下载PDF
TNS320VC5402与AC’97 Codec的接口设计 被引量:1
7
作者 万静华 丁亚军 《单片机与嵌入式系统应用》 2002年第7期47-49,共3页
首先介绍性价比极高的TMS320VC5402与流行的音频编解码AC’97 Codec的接口设计的相关资料,然后从硬件电路和软件部分进行详细的分析。
关键词 TMS320VC5402 AC'97codec 接口 设计
在线阅读 下载PDF
Windows环境下基于软件CODEC的实时视频压缩解压缩技术 被引量:2
8
作者 刘军 叶晓东 周耀华 《计算机工程》 EI CAS CSCD 北大核心 2000年第8期151-153,共3页
讨论了Windows环境下利用软件压缩解压缩器进行实时视频处理的VCM接口技术,并给出了相应的编程实例,同时结合一个局域网视频实时传输系统对软件CODEC技术在多媒体系统中的应用作了一定的探讨.
关键词 软件压缩解压缩器 多媒体系统 codec WINDOWS
在线阅读 下载PDF
SpaceWire CODEC的容错设计和实现 被引量:2
9
作者 程照强 刘淑芬 《空间控制技术与应用》 2012年第3期52-57,共6页
对SpaceWire CODEC进行容错设计是提高其可靠性的重要途径.分析SpaceWire协议的容错性能,介绍SpaceWire CODEC的容错设计方法,通过故障汇入和仿真验证了容错设计的有效性.
关键词 SPACEWIRE codec 容错设计 Hsiao编码 状态机 空时三模冗余
在线阅读 下载PDF
DM6446的Codec Engine原理及应用 被引量:1
10
作者 白桦 杜宇 《黑龙江科技信息》 2009年第5期60-60,共1页
DM6446在一个芯片上集合了ARM内核和DSP内核,为了良好的进行双核交互,可以运用Codec Engine(编解码引擎)软件模块。Codec Engine软件模块可以隐藏复杂的DSP配置和硬件细节,不必修改应用代码就可以实现编解码器的转换,并可以使用第三方... DM6446在一个芯片上集合了ARM内核和DSP内核,为了良好的进行双核交互,可以运用Codec Engine(编解码引擎)软件模块。Codec Engine软件模块可以隐藏复杂的DSP配置和硬件细节,不必修改应用代码就可以实现编解码器的转换,并可以使用第三方提供的Codec,缩短了应用开发的周期。 展开更多
关键词 DM6446 达芬奇 codec ENGINE 编解码引擎
在线阅读 下载PDF
SpaceWire Codec接收端FPGA时序设计 被引量:2
11
作者 唐萍 李慧军 《微计算机信息》 2009年第2期178-179,198,共3页
SpaceWire是一种面向空间应用的数据总线网络,它支持高速、点对点、全双工的串行总线传输。本文实现了基于FPGA的SpaceWire Codec接收端实现过程中时钟的恢复,复位信号的处理,DS信号的检测和处理,介绍了多时钟域的设计方法。
关键词 FPGA SPACEWIRE codec 复位 DS解码 多时钟域设计
在线阅读 下载PDF
C5400系列DSP与AC97 Codec的接口 被引量:1
12
作者 应俊 徐盛 陈健 《电子设计应用》 2003年第8期89-91,104,共4页
本文分析了利用TI公司的C5400系列DSP控制满足AC97标准的音频编解码器,在详细分析DSP片上外设McBSP和DMA特点的基础上,提出了一种非常灵活的接口实现方案。
关键词 C5400系列DSP AC97codec 接口 声卡 音频编解码器
在线阅读 下载PDF
一款音频CODEC芯片的设计与实现
13
作者 倪新永 庄圣贤 舒鑫东 《电子技术应用》 北大核心 2009年第3期52-54,共3页
设计了一种可用于语音信号处理的CODEC芯片,讨论了滤波器组的多级实现。设计中充分利用顺序执行、左右声道共享电路、时分复用等思想优化了电路面积。该芯片设计采用Silterra18标准CMOS工艺流片成功,通过测试完全达到了设计要求。
关键词 音频codec 抽取滤波器 多级实现
在线阅读 下载PDF
New Channel-Aware Modes for VoIP in 3GPP EVS Codec 被引量:1
14
作者 Shenghui Zhao Chongling Rao 《Journal of Beijing Institute of Technology》 EI CAS 2019年第3期491-496,共6页
Aiming at improving rate flexibility of the enhanced voice services (EVS) channel-aware mode for various VoIP applications, two new bit-rate channel-aware modes are proposed in this paper in addition to the existing 1... Aiming at improving rate flexibility of the enhanced voice services (EVS) channel-aware mode for various VoIP applications, two new bit-rate channel-aware modes are proposed in this paper in addition to the existing 13.2 kbit/s mode. Channel-aware mode uses forward error correction by transmitting re-encoded information redundantly for use when the original information is lost or discarded due to late arrival to the receiver. The primary frame bit rate is reduced for the redundant accommodation. A modified quantization scheme is proposed for core encoding regarding the quality degradation. Partial redundant coding is a simplification of that in the existing 13.2 kbit/s channel-aware mode due to the bit constraint. The objective evaluation results of PESQ show that the additional channel-aware modes achieve similar performance in improving the error robustness against missing packets as that of the existing 13.2 kbit/s mode. Multiple bit-rate modes can be dynamically selected in the communication system for more voice services in different bandwidths. On the other hand, optimal allocation based on real-time feedback can adapt to the rapidly-changing network environment as well as possible. 展开更多
关键词 channel-aware MODES 3GPP EVS codec REDUNDANCY error robustness
在线阅读 下载PDF
Codec Negotiation Technologies for 3G 被引量:1
15
作者 Chen Yi 1,2Gao Jie 2Yu Li 2(1. Network Division of ZTE Corporation, Nanjing 210012, China 2. Electronics and Information Department, Huazhong University of Science and Technology, Wuhan 430074, China) 《ZTE Communications》 2007年第1期32-36,共5页
The different formats of codec stream carried in the radio access network and the core network make the double speech encoding/decoding necessary, which degrades the speech quality. Accordingly, codec negotiation tech... The different formats of codec stream carried in the radio access network and the core network make the double speech encoding/decoding necessary, which degrades the speech quality. Accordingly, codec negotiation technologies are necessary for unifying encoding/ decoding in the whole process. Transcoder Free Operation (TrFO), Tandem Free Operation (TFO), and network quality deciding technology are the leading codec negotiation technologies. The TrFO is a mechanism for optimum selection during the establishment of a call. It tries to establish connection between User Equipment (UE) without Transcoder (TC). Its successful fulfillment enables the efficient utilization of bandwidth. The TFO, a standby technology of TrFO, is the negotiation technology of an in-band codec. With it, the user codec stream is free from the compression and decompression by the voice codec, and the quality of voice can accordingly be improved. The network-quantity deciding technology adopts G.711 or G.729 flexibly according to the number of accessed calls. This allows the access of new calls while won’t increase the load of network too much. 展开更多
关键词 TRFO Free TFO codec Negotiation Technologies for 3G MGW
在线阅读 下载PDF
Design and Implementation of Remotely Controlled Vehicle Anti-Theft System via GSM Network 被引量:1
16
作者 T. T. Oladimeji P. O. Oshevire +1 位作者 O. O. Omitola O. E. Adedokun 《Wireless Sensor Network》 2013年第8期151-157,共7页
The purpose of this paper is to build a secured and reliable vehicle anti-theft system which will have the ability to access the vehicle subsystems from a remote location where there is GSM network. And also, the desi... The purpose of this paper is to build a secured and reliable vehicle anti-theft system which will have the ability to access the vehicle subsystems from a remote location where there is GSM network. And also, the design method involves the interfacing of GSM/GPRS modem module with the vehicle ignition subsystem, and the test result shows that it performs some control actions on the vehicle subsystems from a mobile phone, having taken the advantage of the wide coverage area of some GSM networks. Hence the topic is “Remotely Controlled Vehicle Anti-theft System via GSM Network”. 展开更多
关键词 codec—Coder and DECODER GSM—Global system for Mobile Telecommunication GPRS—General Packet Radio SERVICE MODEM—Modulator and DEMODULATOR SMS—Short MESSAGING SERVICE
暂未订购
Cirrus Logic推出集成D类扬声器驱动的高性能音频CODEC 被引量:2
17
《电子与电脑》 2007年第1期65-65,共1页
CimusLoglc公司推出24位立体声CODEC.拓展其用于便携式应用的低功耗音频转换器集成电路系列。借助其高度集成和高性能的音频输出.CS42L52可通过减少大量外部元件而节省整体系统成本。通过为外部扬声器提供每通道1W的高效D类放大.或... CimusLoglc公司推出24位立体声CODEC.拓展其用于便携式应用的低功耗音频转换器集成电路系列。借助其高度集成和高性能的音频输出.CS42L52可通过减少大量外部元件而节省整体系统成本。通过为外部扬声器提供每通道1W的高效D类放大.或每通道44mW的足够功率来驱动立体声耳机,该便携式音频CODEC也具备可利用单电源来运行其内核的灵活性.并可将D类放大器直接连接到电池电源以获得更有效的运行。这些灵活功能组合使CS42L52成为便携式消费电子应用理想的音频CODEC。这些应用包括便携式媒体播放器、游戏设备、MP3播放器附件.IC录音机、数码相机和便携式录像机等。 展开更多
关键词 CIRRUSLOGIC codec 音频转换器 D类放大器 集成电路 扬声器 性能 便携式媒体播放器
在线阅读 下载PDF
Hardware Implementation and System Control Strategy of Videoconference System Based on Rec. H. 261
18
作者 闫安 《High Technology Letters》 EI CAS 1995年第2期73-77,共5页
The design and realization of a videoconference system based on international recommendation are introduced in this paper, and the hardware implementation of video codec based on ITU-T H. 261 is briefly discussed. Fur... The design and realization of a videoconference system based on international recommendation are introduced in this paper, and the hardware implementation of video codec based on ITU-T H. 261 is briefly discussed. Furthermore, the buffer control method and the adaptive control strategy for quantization are proposed, which are adaptive and robust. This system can be operated under the transmission rate ranging from 128kb/s to 2Mb/s. With these strategies for the videoconference system, the high quality image is obtained. The time delay of the system is about half a second. 展开更多
关键词 RECOMMENDATION H. 261 VIDEOCONFERENCE codec BUFFER CONTROL
在线阅读 下载PDF
欧胜推出全新高性能、低功耗CODEC系列
19
《半导体技术》 CAS CSCD 北大核心 2009年第11期1156-1156,共1页
欧胜微电子有限公司宣布推出一个全新的、创新型的低功耗编码解码器(CODEC)系列,旨在增强音频性能和延长各种便携式电池寿命。
关键词 音频性能 codec系列 低功耗 编码解码器 电池寿命 微电子 创新型 便携式
在线阅读 下载PDF
Implementation of ITU-T G.729 Speech Codec in IP Telephony Gateway
20
作者 HUANG Yong feng,ZHANG Jiang ling National Storage System Lab, School of Computer, Huazhong University of Science & Technology, Wuhan 430074,China 《Wuhan University Journal of Natural Sciences》 CAS 2000年第2期159-163,共5页
ITU-T G. 729 is the primarily recommended speech codec by H. 323 standard. This paper describes how to implement G. 729 codec in IP telephony gateway, and goes deep into the programming skills on TMS320C6201 DSP and o... ITU-T G. 729 is the primarily recommended speech codec by H. 323 standard. This paper describes how to implement G. 729 codec in IP telephony gateway, and goes deep into the programming skills on TMS320C6201 DSP and optimizing methods of program code to reduce the speech processing delay time of G. 729 codec. Due to adopting these optimizing methods and programming skills, we have implemented a high-speed speech codec that can process concurrently 20 voice channels with single TMS320C6201 chip in IP telephony gateway. Finally, the paper analyzes the performance results of ITU-T G. 729 codec based on TMS320C6201. 展开更多
关键词 Key words ITU T G. 729 IP telephony gateway speech codec
在线阅读 下载PDF
上一页 1 2 14 下一页 到第
使用帮助 返回顶部