AC-3

High Efficient Algorithm of the Bit Allocation in AC-3 Encoder

AC-3编码器中的高效比特分配算法

Transform Coding Algorithm of AC-3 Digital Audio Compression

AC-3数字音频压缩中的变换编码算法

On the Function and Principium of AC-3 System

AC-3系统功能及原理浅析

This algorithm can greatly enhance both the accuracy and efficiency of the bit allocation in AC-3 encoder .

使得AC-3编码器比特分配的精度和效率均有明显提升。

Multichannel audio coding algorithm ( AC-3 )

多声道音频编码算法（AC-3）

728 . Secondly , the representative techniques of multi-channel audio codec , including MPEG AAC , Dolby AC-3 and DTS etc.

本论文对以MPEGAAC、DolbyAC-3、DTS为代表的多通道音频压缩编解码技术进行了研究。

At first , AC-3 encoder core arithmetic modules are presented in detail , including input filter , transient detection , MDCT , exponents encoding , and bit allocation .

论文详细研究了AC-3编码器核心算法模块：输入滤波、暂稳态判决、MDCT、指数编码、比特分配。

The research on the multi-channel audio codec and the fixed-point implementation methods ; 3 . The system design of the virtual reproduction of AC-3 5.1 channel surround sound by loudspeaker .

多通道音频压缩编解码算法及定点化：AC-3的5.1通路虚拟环绕声系统实现。

Digital audio compression standard AC-3 algorithm has been widely utilized in various fields , such as DVD and HDTV , and is regarded as one or the key techniques for home theatre .

数字音频压缩标准AC-3算法已在广泛领域得到应用，如DVD，HDTV等，是发展家庭影院的主要技术之一。

As audio compression standard of ATSC-HDTV , Dolby AC-3 is a high-quality , low-complexity multichannel audio coder which is used for more and more applications .

作为ATSC-HDTV系统的声音制式标准，杜比AC-3是一种高质量、低复杂度的多声道声音编码压缩技术，被越来越多的应用到各种场合。

The results showed that medical wild rice ( Pc ) and the hybrid Ac-1 and Ac-3 had the strong-resistance to rice leaf roller , which could be used in rice insect-resistant breeding .

结果表明：药用野生稻亲本Pc和种间杂交后代品系Ac鄄1、Ac鄄3对稻纵卷叶螟表现较高抗虫性，可为选育抗虫品种提供参考。

Evaluation results show that by adding the hardware accelerators into the audio DSP core , the ratio of performance to cost is almost increased three times when the AC-3 audio is decoded by the proposed audio DSP core .

面向AC-3解码对音频DSP核的性价比评估表明：为音频DSP核增添硬件加速模块后，其性价比提高了近3倍。

The algorithm and realtime hardware implement complexity of MPEG / Audio , Dolby AC-2 , and AC-3 are introduced . The result of the MPEG / Audio multichannel subject listening tests are introduced also .

介绍MPEG声音编码、DolbyAC－2和AC－3的算法、实时实现的复杂度以及多声道主观测试结果。

The digital audio standards being widely applied currently include MPEG-1 , MPEG-2 , Dolby AC-3 and DTS . All the standards ' intellectual properties are belonging to foreign enterprises . It takes high patents fees when our country uses these technologies .

目前广泛应用的数字音频标准包括MPEG-1、MPEG-2、杜比AC-3、DTS等，而这些标准的知识产权归属于国外企业，那么我国在使用这些技术时就必须向其他国家交纳高额的专利费。

Currently , this encoder can response to the external UART serial port interrupt to implement the encoding standard switching , and sample PCM in real time , accomplish AC-3 encoding algorithm without delay , transmit the encoded stream through S / PDIF interface .

目前，该编码器能够响应外部UART串口的中断请求来实现编码标准的切换，并能够实时采集数据，实时完成AC-3编码算法，通过S/PDIF接口实时输出编码码流。

In order to realize real-time AC-3 decoding , optimized decoding algorithms such as the multi-decomposition IMDCT algorithm and Goldschmidt divider algorithm are adopted . The IMDCT hardware accelerator and bit - parsing module etc. are added into the audio DSP core .

为了实现5.1声道的AC-3的实时解码，采用了多重分解的IMDCT迭代算法、Goldschmidt除法算法等优化算法，并为音频DSP核设计了IMDCT硬件加速器、码流分解模块等硬件加速模块。