1、毕业设计（论文）外文资料 江西理工大学应用科学学院 毕业设计 (论文 )外文资料翻译 系 别： 信息 专 业： 电子信息工程 班 级： 081 姓 名： 李宏成 学 号： 08060308116 附 件： 1.外文资料翻译译文； 2 外文原文 指导教师评语： 签名： 年 月 日 毕业设计（论文）外文资料 1 Dolby laboratory on Dolby Author: Tiger Multichannel perceptual coding Dolby AC-3is a kind of efficiency, quality and functional aspects with unp
2、recedented effect perceptual digital audio coding technology. From the beginning of 1992, it has been for the cinema provide multichannel digital audio system and achieved in 1994into the two channel I BS application. It in the cassette and disc type family television system for transmitting multich
3、annel digital sound function has been to the consumer electronics industry with very excited. In the United States, high definition television ( HDTV ) broadcasting the selected Dolby digital surround sound transmission, estimated that in 1996will be put into a test screening. Many have been announc
4、ed and the potential applications of the technology of test shows, Dolby AC-3decoder has a beautifully versatility. AC-3 is not a single machine system, but a kind of use can make such as bit rate and number of channels such parameters to adapt to different special application flexible procedures fo
5、r the treatment of familial. Various types of all decoder in order to work on the same principle as the foundation, and designed to take full account of the future need for compatibility and adaptability. Important is, Dolby AC-3will be high quality sound and excellent digital efficiency is very per
6、fect combination. Because of the Dolby Laboratory for more than 20 years focus on human auditory research, in the development of signal processing field has accumulated rich experience, so, although AC-3than in the CD disk to the last channel lower bit rate to create a multi-channel surround sound,
7、however, it makes the sound quality fully meet the listener expectations. Audio : past present and future In 30, the famous Baer Laboratories began using the three channel stereo sound. In 50, when the stereo into public movie, it uses the channel in four above, sometimes reaching over seven channel
8、s. A few years later, the stereo into families, since all of the phonograph records only with dual channel matching, so the family leave acoustic device only by dual channel playback, the technical limitations, can not the listener will generally two-channel stereo as the home audio selection criter
9、ia. But the film makers have channel 1( left, right, center ) and surround channel2as a compelling vivid sound minimum requirements. This can be from 70 time end, eighty time period the film industry widely adopted Dolby stereo to record film confirmed, Dolby stereo is the principle, let four channe
10、l matrix coding input two optical sound track, then an appropriate audio processor will restore it into four channels matrix coding reproduction. When Dolby stereo film is converted into audio signals, four channel coding retained the dubbing integrity, from 80 time begin first, Dolby surround has m
11、ade multiple channel decoding into family time, today, tens of thousands of home audio systems are equipped with Dolby surround sound system, in fact, multi-channel surround sound system sales has been far 毕业设计（论文）外文资料 2 beyond the two-channel stereo system sales, at present, Dolby surround sound ha
12、s been widely used in film, TV and music on CD recording studio, and its accompanying family Dolby surround systems on the market rapid development. With multi-channel audio in consumer electronics in the field of rapid growth, a more advanced technology was born, the technology is born there is not
13、hing comparable to this, it has simulated realistic sound effects, and can satisfy various listening conditions and high demand cannot imagine adaptability, this is Dolby AC-3decoding technology Dolby AC-3 decoder, the successful development and application, is the worlds electro-acoustic industry a
14、 major achievement. Dolby AC-3 In 1987, high-definition television channel in the United States has officially become the standard process, its audio track is used for the first time in the four channel matrix encoding conversion for transmission of digital code stereo. However, by 1990, in order to
15、 avoid audio matrix are affected, four mono or stereo combined configuration as the optimal configuration. Due to time technical limitations, such an arrangement would have to increase by at least a bit rate. It is in this context, Dolby AC-3was born. It has the advantage of only two independent ste
16、reo more code rates can realize multi-channel audio code. Dolby advanced to the transmission of the code technology, such as Dolby AC-2 decoder for Dolby AC-3s successful development paved the way, but the complexity of multichannel code also need further research, including a new type of bit alloca
17、tion technique. The Dolby laboratory is established by Rui Milton Dolby. Dr. Dolby was born in 1933 in the United States Portland Oregon City, grew up in the San Francisco Bay area. At the age of 16 he was still in high school, in Ampex company works. The company is the United States s first product
18、ion of magnetic tape recording equipment manufacturers. Later, he is responsible for the development of the company developed the worlds first practical VCR portion of an electronic circuit. In 1957 Dolby graduated from Stanford University, University of Cambridge, Marshall won the British provided
19、scholarships, study of L-band X light. In 1961 he received a doctors degree in physics. In 1963, he accepted the UN appointed to India as a two-year consultant. As an amateur recording enthusiasts, Dr. Dolby over the years to recognize on the tape recording audio or video signal when background nois
20、e on the recording quality damage. While in India he began thinking seriously about a noise reduction without compromising the recording quality approach. His exploration of these became the Dolby A B noise reduction and noise reduction, noise reduction system based on C. In 1965, returning to Engla
21、nd, in London he established his own laboratory in order to carry out in India he thought scheme. Set up in 1968 to the Dolby lab named company. Although the company was founded10 years ago, the work of the centre in the UK, but it has been an American company. After 1976, the companys main work mov
22、ed to San francisco. In 1965, the first Dolby A type noise reducer ( A representing audio Audio ) production out of. The design of the system for a variety of audio noise reduction application, especially can solve the studio recording tape when the tape recorder generated noise. Until 1966, there have been
