Game Development Reference
In-Depth Information
Fig. 8.9
G/GB picture signalization
Fig. 8.10
S-picture signalization
each random access point, the S-picture can obtain the G/GB stream from system,
then the S-picture can be decoded. Moreover, related with the reference picture
management, an improved mechanism is designed to deal with the MBG so as to
support a no-delay, no-frame-drop, and real-time encoding.
8.4.2 Modeled Background Picture-Based Coding
For surveillance video coding, in AVS and AVS2, G-picture can be either selected
from input pictures or one picture generated by background picture modeling, called
modeled background picture (MBG) to predict its following two pictures and the
S-pictures. To support this, more tools are developed to utilize MBG for better inter-
prediction.
Firstly, the segment-and-weight based running average (SWRA) for background
modeling is future improved in AVS2W by assigning a larger weight on the fre-
quent values in the averaging process. SWRA divides the pixels at a position
in the training frames into temporal segments with their own mean values and
weights. And then, it calculates the running and weighted average result on the
mean values of the segments. In the process, pixels in the same segment have the
same background/foreground property and the longer segments have larger weights.
Experimental results show that SWRA can achieve good performance yet without
