通信及電子信息工程專業(yè)英語第8單元

1、Unit 8 MultimediaMultimediaUnit 8 Multimediav The word multimedia is being used to describe a mixture of hardware .software and applications, with a consequent confusion in peoples minds as to what it is. it is a confusion situation that could lead to a missed opportunity for industry to develop a n

2、ew marketplace. The term multimedia literally means many forms of communication and in a sense we have always been immersed in a multimedia environment because we are being that respond to sound , light, touch, and ideas. This is essentially an interactive environment.v “多媒體多媒體”這個詞正在被用于描述混合的硬件，軟件和應用

3、這個詞正在被用于描述混合的硬件，軟件和應用程序，伴隨著人們心中隨之而來的混亂。這是一個混亂的程序，伴隨著人們心中隨之而來的混亂。這是一個混亂的局面，它可能導致錯過一個工業(yè)發(fā)展新市場的機會。多媒局面，它可能導致錯過一個工業(yè)發(fā)展新市場的機會。多媒體這一術語字面上的意味著許多形式的交流，就某種意義體這一術語字面上的意味著許多形式的交流，就某種意義來說我們一直浸泡在多媒體的環(huán)境里。因為我們正在回應來說我們一直浸泡在多媒體的環(huán)境里。因為我們正在回應聲，光，觸摸和想法。這實質(zhì)是一個互動的環(huán)境。聲，光，觸摸和想法。這實質(zhì)是一個互動的環(huán)境。 Unit 8 Multimediav In the modern p

4、resentation of multimedia we now have the technology that can begin to move towards an ability ,already held by the human being ,in that by using computer technology, such as CD-ROM, not only can we bring together audio and visual images but also be interactive with other computer users.v 在現(xiàn)在多媒體介紹中，

5、我們現(xiàn)在有技術可以開始面向能力。在現(xiàn)在多媒體介紹中，我們現(xiàn)在有技術可以開始面向能力。它已經(jīng)通過人類舉行，利用計算機技術。如光驅(qū)，不僅能它已經(jīng)通過人類舉行，利用計算機技術。如光驅(qū)，不僅能為我們帶來共同的音頻和視覺圖像組合在一起。而且也與為我們帶來共同的音頻和視覺圖像組合在一起。而且也與其他的電腦用戶互動。其他的電腦用戶互動。 Unit 8 Multimediav Perhaps the biggest reason for the explosion of multimedia offerings is the enormous advances in personal desk top com

6、puter , This computer advance would appear to bring multimedia facilities within the reach of the majority of homes for about US$1 600; this system might consist of a 486 processor with 4Mbytes of RAM and 340 Mbytes of hard disc storage ,with a colour monitor ,CD-ROM, sound system ,language and lear

7、ning systems and Windows and Lotus Applications .This sort of specification is aimed at the personal ,home computer market and is probably more for games and education.v 也許最大的原因是多媒體產(chǎn)品爆炸是個人臺式電腦的巨大進步。這臺電也許最大的原因是多媒體產(chǎn)品爆炸是個人臺式電腦的巨大進步。這臺電腦事先似乎使多媒體設施達到大多數(shù)家庭的大約腦事先似乎使多媒體設施達到大多數(shù)家庭的大約1600美元。這個系統(tǒng)美元。這個系統(tǒng)可能包括一個可能

8、包括一個486處理器的處理器的4M內(nèi)存和內(nèi)存和340M的硬盤存儲，彩色顯示器，的硬盤存儲，彩色顯示器，光驅(qū)，音響系統(tǒng)，語言學習系統(tǒng)，光驅(qū)，音響系統(tǒng)，語言學習系統(tǒng)，Windows 和和 Lotus應用。這種規(guī)應用。這種規(guī)范是針對個人，家用電腦市場。更多的可能是為了教育和游戲。范是針對個人，家用電腦市場。更多的可能是為了教育和游戲。 Unit 8 Multimediav The first element associated with multimedia is perhaps the CD-ROM, now considered a mature technology. The CD-ROM

9、is used to store data that represents visual imagery and current units can store up to 650 Mbytes of data. The standards of multimedia can be found in what is known as the ITU White Book, which brings together various standards for CD-ROM and video compression and it is essential that these two area

10、s of standards are taken together.v第一個相關多媒體的元素可能是光驅(qū)，現(xiàn)在被認為是第一個相關多媒體的元素可能是光驅(qū)，現(xiàn)在被認為是一個成熟的技術。光驅(qū)被用來存儲代表視覺圖像和當一個成熟的技術。光驅(qū)被用來存儲代表視覺圖像和當前單元可以最多存儲前單元可以最多存儲650M字節(jié)的數(shù)據(jù)。多媒體標準字節(jié)的數(shù)據(jù)。多媒體標準可以被發(fā)現(xiàn)，從被稱為國際電信聯(lián)盟的白皮書中。它可以被發(fā)現(xiàn)，從被稱為國際電信聯(lián)盟的白皮書中。它匯集了各種光驅(qū)和視頻壓縮的標準。它至關重要的是匯集了各種光驅(qū)和視頻壓縮的標準。它至關重要的是這兩個地區(qū)的標準聯(lián)系起來。這兩個地區(qū)的標準聯(lián)系起來。 Unit 8 Mul

11、timediav A crucial element in the provision of multimedia is the use of compressed video .Without compression the amount of storage that would have to be provided by the CD-ROM would be immense, or you would only be able to store 15 seconds of a full motion picture. If compression is applied to the

12、motion pictures experts group(MPEG-1) standard, then a 650 Mbytes CD-ROM can hold either 72 minutes of video, or 19 hours of audio, or 7 000 still photographs.v 提供的多媒體中一個關鍵的因素是壓縮視頻的使用提供的多媒體中一個關鍵的因素是壓縮視頻的使用.無壓縮無壓縮存儲的不得不提供巨大的光盤，否則你只可以存儲一個存儲的不得不提供巨大的光盤，否則你只可以存儲一個15秒的完整電影。如果壓縮應用于運動圖像專家組秒的完整電影。如果壓縮應用于運動圖

13、像專家組（MPEG-1）標準。然后）標準。然后650MB的光盤可以容納的光盤可以容納72分分鐘的視頻，或鐘的視頻，或19小時的音頻，或小時的音頻，或7000 張靜態(tài)照片。張靜態(tài)照片。Unit 8 Multimediav The standards for moving pictures are set by MPEG as international standards. The two levels are MPEG-1, which sets the provision of consumer quality of video and audio and MPEG-2,which sets

14、 the higher standards for professional, broadcast images and also looks to define high definition television.v 移動圖片的標準是由移動圖片的標準是由MPEG設定作為國際標準。兩個層次設定作為國際標準。兩個層次的是的是MPEG-1，它設定消費者提供質(zhì)量的音頻和視頻。，它設定消費者提供質(zhì)量的音頻和視頻。MPEG-2設置了高標準的專業(yè)，廣播圖像，也定義了高清設置了高標準的專業(yè)，廣播圖像，也定義了高清晰的電視。晰的電視。 Unit 8 Multimediav MPEG-2 looks at m

15、ore than pictures, it looks at the associated sound, storage methods, bit rates needed, coding algorithms, etc. Modern encoders are not only used in the CD-ROM area, but also as a means of transmitting signals, they use a number of digital signal processor to form a vision encoder.v MPEG-2的清晰度看起來更多于

16、圖片。它看來相關聯(lián)的聲的清晰度看起來更多于圖片。它看來相關聯(lián)的聲音，存儲方法，比特率需求，編碼算法等?，F(xiàn)代的編碼器音，存儲方法，比特率需求，編碼算法等?，F(xiàn)代的編碼器不僅使用在光盤地區(qū)，而且還作為一種工具傳輸信號，他不僅使用在光盤地區(qū)，而且還作為一種工具傳輸信號，他們使用的許多數(shù)字信號處理器形成了視覺編碼器。們使用的許多數(shù)字信號處理器形成了視覺編碼器。v Unit 8 Multimediav he problem for the CD-ROM industry is that although they know what the data rate will be if the picture

17、 signal is encoded, they have different ways of putting the data onto a disc. As standards evolve this problem may be disappear, but in the meantime anyone looking to upgrade their multimedia systems has to look not only at the MPEG encoder but also at the PC, which must be at least a 486 standard w

18、ith a clock speed of at least 25 MHz, because anything to a lower standard will give an inferior performance regardless of where the data is stored.v 光盤行業(yè)的問題是雖然他們知道數(shù)據(jù)傳輸速率將像圖片信號編碼他們有不光盤行業(yè)的問題是雖然他們知道數(shù)據(jù)傳輸速率將像圖片信號編碼他們有不同的方式把數(shù)據(jù)刻錄到光盤。作為標準的演變，這一問題可能消失。但在同的方式把數(shù)據(jù)刻錄到光盤。作為標準的演變，這一問題可能消失。但在此期間，尋找提升它們多媒體系統(tǒng)已不單看此期間

19、，尋找提升它們多媒體系統(tǒng)已不單看MPEG的編碼器，而且在個的編碼器，而且在個人電腦。其中必須至少有一個人電腦。其中必須至少有一個486標準的時鐘速率至少標準的時鐘速率至少25兆赫茲。因為兆赫茲。因為任何一個較低的標準會給一個弱質(zhì)的性能，無論數(shù)據(jù)存儲在什么地方。任何一個較低的標準會給一個弱質(zhì)的性能，無論數(shù)據(jù)存儲在什么地方。 Unit 8 Multimediav If we consider the business area of multimedia applications, the provision of video is crucial and that video informati

20、on must come to user in real time and therefore be processed in real time. This means that any system must conform to the CCITT MPEG-2 standard. The technology to do this has moved on tremendously in the last few years due to the need to reduce the cost of transmitting data over the network. The enc

21、oders and decoders for video are now manufactured with a minimum of integrated circuits.v 如果我們考慮多媒體應用的業(yè)務領域，提供的視頻是至關如果我們考慮多媒體應用的業(yè)務領域，提供的視頻是至關重要的。視頻信息必須實時面向用戶。因而處理是實時的。重要的。視頻信息必須實時面向用戶。因而處理是實時的。這意味著任何系統(tǒng)必須符合這意味著任何系統(tǒng)必須符合CCITT（國際電話電報咨詢委（國際電話電報咨詢委員會）的員會）的MPEG-2標準。這樣的技術已經(jīng)在過去的幾年由標準。這樣的技術已經(jīng)在過去的幾年由于需要降低通過網(wǎng)絡來傳

22、輸數(shù)據(jù)成本。視頻的編碼器和譯于需要降低通過網(wǎng)絡來傳輸數(shù)據(jù)成本。視頻的編碼器和譯碼器碼器 是現(xiàn)在最低集成的電路制造。是現(xiàn)在最低集成的電路制造。 Unit 8 Multimediav What then are the problems for the designer? The individual elements of multimedia are already handled by a standard 486 personal computer, such things as audio, graphics and text, but the major challenge is in

23、 real time video, for this is the major business requirement and a necessityif multimedia systems are to become standard items for the desktop. v 然后然后什么是設計師的問題？個人多媒體元素已經(jīng)由一個標準的什么是設計師的問題？個人多媒體元素已經(jīng)由一個標準的486個人的電腦處理，諸如音頻，圖形和文字。但主要的挑戰(zhàn)是實時的視個人的電腦處理，諸如音頻，圖形和文字。但主要的挑戰(zhàn)是實時的視頻。這是主要的業(yè)務需求和必要多媒體系統(tǒng)成為臺式機的標準項目。頻。這是主要的

24、業(yè)務需求和必要多媒體系統(tǒng)成為臺式機的標準項目。Unit 8 Multimediav This real time processing requires a vast amount of data storage and this is a function of the amount of information contained in a colour picture, for instance a normal 640480 pixel colour picture requires well over 1 Mbyte of storage to give the required q

25、uality, though for full motion video this is increased up to 100 Mbytes of data.v 這種實時處理需要大量的數(shù)據(jù)存儲。這是一個功能包含大這種實時處理需要大量的數(shù)據(jù)存儲。這是一個功能包含大量信息的彩色圖片。例如一個正常的量信息的彩色圖片。例如一個正常的640*480像素的彩像素的彩色圖片需要超過色圖片需要超過1MB的存儲提供所需要的質(zhì)量。雖然全的存儲提供所需要的質(zhì)量。雖然全動態(tài)視頻，這是增加到動態(tài)視頻，這是增加到100MB的數(shù)據(jù)。的數(shù)據(jù)。 Unit 8 Multimediav The spread of multime

26、dia users is not just a function of technology, and it is certainly not an stoppable process. The key to its take-up is in the successful selling of video and television services, which are often gathered under the general title of video-on-demand (VOD) interactive services. A typical VOD architectu

27、re takes trunk and access networks into account. The video server is the key to on-demand services. The video server will store a large number of programs that can be instantly accessed by a large number of individual subscribers, it is stored in a compressed form to save space5.v 多媒體用戶的傳播不僅僅是技術的功能，這肯定不是一個阻斷過程。它的多媒體用戶的傳播不僅僅是技術的功能，這肯定不是一個阻斷過程。它的采取行動的關鍵是成功的視頻和電視服務的銷售。這是經(jīng)常聚集在主標題采取行動的關鍵是成功的視頻和電視服務的銷售。這是經(jīng)常聚集在主標題下的視頻的需求（視頻點播）互動服務。一個典型的視頻點播架構(gòu)需要考下的視頻的需求（視頻點播