Đang chuẩn bị liên kết để tải về tài liệu:
Lecture Data communications and networks: Chapter 29 - Forouzan

Chapter 29 discusses multimedia and a set of wiely-used application programs. These programs have generated new issues such as the need for new protocols in other layers to handle the specific problems related to multimedia. We briefly discuss these issues in this chapter. | Chapter 29 Multimedia Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 29. Figure 29.1 Internet audio/video 29. Streaming stored audio/video refers to on-demand requests for compressed audio/video files. Note 29. Streaming live audio/video refers to the broadcasting of radio and TV programs through the Internet. Note 29. Interactive audio/video refers to the use of the Internet for interactive audio/video applications. Note 29. 29-1 DIGITIZING AUDIO AND VIDEO Before audio or video signals can be sent on the Internet, they need to be digitized. We discuss audio and video separately. Digitizing Audio Digitizing Video Topics discussed in this section: 29. Compression is needed to send video over the Internet. Note 29. 29-2 AUDIO AND VIDEO COMPRESSION To send audio or video over the Internet requires compression. In this section, we discuss audio compression first and then video compression. Audio Compression Video Compression Topics discussed in this section: 29. Figure 29.2 JPEG gray scale 29. Figure 29.3 JPEG process 29. Figure 29.4 Case 1: uniform gray scale 29. Figure 29.5 Case 2: two sections 29. Figure 29.6 Case 3: gradient gray scale 29. Figure 29.7 Reading the table 29. Figure 29.8 MPEG frames 29. Figure 29.9 MPEG frame construction 29. 29-3 STREAMING STORED AUDIO/VIDEO Now that we have discussed digitizing and compressing audio/video, we turn our attention to specific applications. The first is streaming stored audio and video. First Approach: Using a Web Server Second Approach: Using a Web Server with a Metafile Third Approach: Using a Media Server Fourth Approach: Using a Media Server and RTSP Topics discussed in this section: 29. Figure 29.10 Using a Web server 29. Figure 29.11 Using a Web server with a metafile 29. Figure 29.12 Using a media server 29. Figure 29.13 Using a media server and RTSP 29. 29-4 STREAMING LIVE AUDIO/VIDEO | Chapter 29 Multimedia Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 29. Figure 29.1 Internet audio/video 29. Streaming stored audio/video refers to on-demand requests for compressed audio/video files. Note 29. Streaming live audio/video refers to the broadcasting of radio and TV programs through the Internet. Note 29. Interactive audio/video refers to the use of the Internet for interactive audio/video applications. Note 29. 29-1 DIGITIZING AUDIO AND VIDEO Before audio or video signals can be sent on the Internet, they need to be digitized. We discuss audio and video separately. Digitizing Audio Digitizing Video Topics discussed in this section: 29. Compression is needed to send video over the Internet. Note 29. 29-2 AUDIO AND VIDEO COMPRESSION To send audio or video over the Internet requires compression. In this section, we discuss audio compression first and then video compression. Audio Compression Video .