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374 17 Denoising in Communications
Figure 17.3 Cactus overview.
At the sender, a video sequence is first divided into group of pictures (GOP).
Commonly used GOP sizes vary from 4, 8, 16 to 32 depending on the application
requirements. We select GOP size equaling to 8 in our system. Each GOP is first de-
correlated in the temporal axis via motion-compensated temporal filtering (MCTF).
The motion information, including mode and motion vector, needs to be faithfully
received by every receiver, so they are entropy coded and transmitted using a robust
digital scheme. We adopt the combination of 1/2-rate channel coding and binary
phase shift keying (BPSK) ...