Cisco D9054 Installation And Operation Manual page 64

Video Menu,
Continued
H.264, GOP, Dynamic GOP
Parameters:
Description:
H.264, GOP, GOP Length
Parameters:
Description:
H.264, GOP, B Pictures
Parameters:
Description:
H.254, Chroma
Parameters:
Description:
H.264, Rate Mode
Parameters:
Description:
4-10
Enable, Disable.
Dynamic GOP should always be enabled for best video quality.
Dynamic GOP adds to end-to-end delay. If lower end-to-end delay
is more important than video quality, then Dynamic GOP should be
turned off (disabled).
When Dynamic GOP is on (the default is off), the encoder selects
between two hierarchical GOP structures, one with 3 B-pictures and
the other with 15 B-pictures. The selection is automatically based on
video content (scene's spatio-temporal complexity).
When using Dynamic GOP, the GOP Length must be a multiple of
16 (i.e., 16, 32, 48, etc).
A figure in the range from 1 to 255.
The GOP length and the number of B-pictures influences the picture
quality and delay.
0, 1, 2 or 3.
The GOP length and the number of B-pictures influences the picture
quality and delay.
The following table shows example settings and their meaning:
GOP Length
1
2
4
12
4:2:0.
You typically use 4:2:0 in distribution applications.
Variable, Fixed, Statmux.
Fixed is used for constant bit rate support. Variable (Capped VBR)
is constrained to a maximum rate whereby Statmux allows you set
video bit rate (i.e., minimum and maximum) which the encoder can
operate within.
D9054 HDTV Encoder Intstallation and Operation Guide
B Pictures Meaning
0 I only
1 IB
0 IPPP
2 IBBPBBPBBPBB
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