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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