This chapter reviews the basic elements of recent approaches to Joint Source-Channel Coding (JSCC) for wired and wireless systems alike. It presents rate-distortion definitions in addressing the need for JSCC and describes the basic components in a video compression and transmission system. It discusses the channel coding techniques that are widely used for video communications. Because of the high bandwidth of the raw video data, compression is necessary for reducing the source redundancy. With ideal lossless compression, source redundancy can be entirely removed without any quality loss. Because the minimum bit rate achieved using lossless compression is usually much higher than the available channel capacity, lossy compression is generally required for video transmission applications. The same way entropy determines the lowest possible rate for lossless compression, the rate-distortion (R-D) theory addresses the same question for lossy compression. The term "channel encoding" is used in a general way to include modulation and demodulation, power adaptation, packet scheduling, and data rate adaptation. An overview of the state-of-the-art implementations of JSCC in various network infrastructures is also presented in the chapter.
ASJC Scopus subject areas
- Computer Science(all)