Advances in Visual Data Compression and Communication

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Part II

Scalable Video Coding

This part studies scalable video coding (SVC). The fundamental problem with

SVC is closely related to motion compensation. As we have discussed in Chapter 2,

every input picture will subtract a predictive picture in motion compensation. The

predictive picture must be exactly the same at the encoder and decoder. If there are

some differences between the predictive pictures used in the encoder and the decoder,

the differences in different pictures will be accumulated and thus the quality of de-

coded pictures will continuously drop, which is known as drifting error. In SVC, it is

hard to keep the predictive picture the same in both the encoder and decoder because

part of the compressed data may be dropped during