Currently , the demands of video communication on low bit - rate channels ( 10kb / s ~ 60kb / s ) , such as wireless channel and telephone network , are becoming more and more comprehensive 目前，针对低速率信道( 10kb / s 60kb / s )如无线通道和电话线上的视频通讯的应用需求越来越广泛。
A fpga is used as the controller , performing the necessary processing such as eliminating the head of the encoded data frame , storing the speech data into fifo and transmitting it 控制芯片采用fpga ，完成复位、分频及对已编码帧数据进行去帧头、在fifo中暂存等处理并以低速率发送。
Pitch detection is one of the most important tasks in low - rate speech coding field . the accuracy of pitch detection will affect the performance of the whole codec 基音检测是低速率语音编码领域的一个非常重要的问题,准确检测语音信号的基音周期非常关键,它直接影响到整个声码器的性能。
Many research institutes around the world are focusing on and developing wi speech coding algorithm , expecting to give a communication quality of synthesized speech at 2kb / s or even below 目前国际上许多研究机构正在集中研究和开发该算法,期望在2kb / s或更低速率产生通信质量的重建语音。
The system includes a digital video codec / decodec chip adv611 based on wavelet - transform , a saa7111 chip and a dsp chip tms320vc5402 controlling the systems 该系统以tms320vc5402为主控芯片，选用小波压缩芯片adv611和图像处理芯片saa7111设计了硬件电路，较好地实现了视频信号低速率传输的问题。
In this paper , the background knowledge of speech coding , the theory and development is firstly introduced , then g . 729 standard and appendix a is analyzed systematically 本论文在介绍了低速率语音编码技术的背景知识后，系统地阐述了g 729语音编码标准及其附录a ，着重从原理上分析了算法中的关键技术。
At low bit - rates , because of limitation of the budget bits , we can make the quality of regions absorbing eye focus higher than other regions by adjusting bit - allocation 在低速率编码条件下，由于总的允许分配比特数量有限，通过调整位分配过程，可以使得某些人眼感兴趣的区域的图像恢复质量高于其它区域。
Recently , low bit - rate speech coding has developed greatly . the research on low bit - rate coder at 4kb / s and below with communication quality has become one of the most attention at present 近年来低速率语音编码得到了巨大的发展,目前,在4kb / s以下速率实现具有通信质量的编码器已成为当今语音编码领域的一大研究热点。
Waveform interpolation speech coding is one of the most potential low - rate speech coding algorithms in recent years . with high performance , wi technique has been widely concerned 波形内插( waveforminterpolation , wi )语音编码是近年来发展起来的一种非常有潜力的低速率语音编码算法,因其良好的性能,受到了研究人员的广泛关注。
The g729a , a new issued speech compressed coding standard at 8kbit / s , is one of the optional coding standards of h . 323 , which is multimedia meeting system standard based on ip network 729a是国际电信联盟新颁布的编码速率为8kb s的低速率语音压缩编码标准，它是基于ip网络的多媒体会议系统标准h 323可选的语音压缩编码标准之一。
