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Chapter 25 - Multimedia. Recent advances in technology have changed our use of audio and video. In the past, we listened to an audio broadcast through a radio and watched a video program broadcast through a TV. We used the telephone network to interactively communicate with another party. But times have changed. People want to use the Internet not only for text and image communications, but also for audio and video services. In this chapter, we concentrate on applications that use the Internet for audio and video services. | Chapter 25 Upon completion you will be able to: Multimedia Know the characteristics of the 3 types of services Understand the methods of digitizing and compressing. Understand jitter, translation, and mixing in real-time traffic Understand the role of RTP and RTCP in real-time traffic Understand how the Internet can be used as a telephone network Objectives TCP/IP Protocol Suite Figure 25.1 Internet audio/video TCP/IP Protocol Suite Streaming stored audio/video refers to on-demand requests for compressed audio/video files. Note: TCP/IP Protocol Suite Streaming live audio/video refers to the broadcasting of radio and TV programs through the Internet. Note: TCP/IP Protocol Suite Interactive audio/video refers to the use of the Internet for interactive audio/video applications. Note: TCP/IP Protocol Suite 25.1 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. The . | Chapter 25 Upon completion you will be able to: Multimedia Know the characteristics of the 3 types of services Understand the methods of digitizing and compressing. Understand jitter, translation, and mixing in real-time traffic Understand the role of RTP and RTCP in real-time traffic Understand how the Internet can be used as a telephone network Objectives TCP/IP Protocol Suite Figure 25.1 Internet audio/video TCP/IP Protocol Suite Streaming stored audio/video refers to on-demand requests for compressed audio/video files. Note: TCP/IP Protocol Suite Streaming live audio/video refers to the broadcasting of radio and TV programs through the Internet. Note: TCP/IP Protocol Suite Interactive audio/video refers to the use of the Internet for interactive audio/video applications. Note: TCP/IP Protocol Suite 25.1 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. The topics discussed in this section include: Digitizing Audio Digitizing Video TCP/IP Protocol Suite Compression is needed to send video over the Internet. Note: TCP/IP Protocol Suite 25.2 AUDIO AND VIDEO COMPRESSION To send audio or video over the Internet requires compression. The topics discussed in this section include: Audio Compression Video Compression TCP/IP Protocol Suite Figure 25.2 JPEG gray scale TCP/IP Protocol Suite Figure 25.3 JPEG process TCP/IP Protocol Suite Figure 25.4 Case 1: uniform gray scale TCP/IP Protocol Suite Figure 25.5 Case 2: two sections TCP/IP Protocol Suite Figure 25.6 Case 3: gradient gray scale TCP/IP Protocol Suite Figure 25.7 Reading the table TCP/IP Protocol Suite Figure 25.8 MPEG frames TCP/IP Protocol Suite Figure 25.9 MPEG frame construction TCP/IP Protocol Suite 25.3 STREAMING STORED AUDIO/VIDEO We turn our attention to a specific applications called streaming stored audio and video. We use four .
