From Multimedia Networking: From Theory to Practice

5.1 Evolution of Digital Video Coding

Digital video coding has gone through a long history of technological evolution (see Figure 5.2). The first practical digital video coding standard was H.261, proposed by the International Telecommunication Union (ITU-T) in 1990 [2], originally designed for transmission over ISDN lines on which data rates are multiples of 64 kbps. The coding algorithm was designed to be able to operate at a data rate between 40 kbps and 2 Mbps. The standard supports both CIF (352 288) and QCIF (176 144) video frames with the 4 : 2 : 0 chroma subsampling. Owing to the pioneering effort of H.261 design and collaborative development, all subsequent international video coding standards (MPEG-1, MPEG-2/H.262, H.263, and even H.264) have been following a similar architectural design and standardization process. The H.261 standard is part of the H.320 group of standards for audio and visual communications. It forms the heart of many early-stage digital video applications in video conferencing and video communications systems, such as studio-based and desktop video conferencing, surveillance and monitoring, telemedicine, and computer-based training. In its later revision (the so-called version 2), H.261 allows a backward-compatible scheme for sending still picture graphics with 704 576 resolution.


Figure 5.2: The evolution of digital video coding standards.

As discussed in Chapter 3, MPEG-1 is a system-level standard which defines a group of audio and video (AV) coding and compression standards agreed upon by the MPEG committee. The MPEG-1 video coding standard [3] was...

Copyright Cambridge University Press 2009 under license agreement with Books24x7

Products & Services
Digital Video Recorders
Digital video recorders record and store video camera output in digital form on disk.
Video Conferencing Equipment
Video conferencing equipment enables meeting participants at different locations to communicate via two-way video with simultaneous audio transmissions.
Video and Audio Software
Video and audio software is used to process audio and video signals. Applications can include motion analysis, security, ID systems, etc.
Teleconferencing and Webcast Services
Teleconferencing and webcast service providers host video conferencing or webinars for business presentations.
Audio Visual Services
Audio visual service providers design, integrate, and install multimedia equipment for corporate, production, and broadcasting applications.

Topics of Interest

5.2 Compression Techniques for Digital Video Coding As with image coding, the objectives of video coding are bitrate reduction in storage and transmission by the use of both statistical and...

Overview There are several standards for video conferencing, as shown in Table 10.1. Figures 10.1 through 10.3 illustrate the block diagrams of several common video conferencing systems. Table 10.1:...

5.4 MPEG-1 and MPEG-2 Video Coding The Moving Picture Experts Group (MPEG) was started in 1988 as a working group within ISO/IEC with the aim of defining standards for the digital compression of...

Chapters List Chapter 6.1: Basic Concepts and Techniques of Video Coding and the H.261 Standard Chapter 6.2: Interframe Subband/Wavelet Scalable Video Coding Chapter 6.3: Digital Video Transcoding...

with Jean Felipe Fonseca de Oliveira and Jos Ewerton Pombo de Farias 3.1 An Overview of Audio and Video Compression MPEG-1 and MPEG-2, developed by the Moving Pictures Expert Group (MPEG) within the...