VCS VIP 1000, User Manual

Page: 42 / 118

Configuring the Transmitter Chapter 6
42 VIP 10 / VIP 1000
Select the structure for the GOP. You can choose between:
]
I
I-frames only
]
IP
an I-frame followed by several P-frames
]
IPB
an I-frame followed by several substructure sequences, each consisting of a
P-frame and a B-frame
]
IPBB
an I-Frame followed by several substructure sequences, each consisting of a
P-frame and two B-frames
GOP length:
Enter the image interval between I-frames here. The value will depend on the
GOP structure selected. It must always be a multiple of the P- frames and B-
frames in the GOP structure.
In the context of the GOP structure IPB , a length of 4 means that an I-frame is
followed by a total of four other frames, which are alternately P- and B-frames.
The resultant image structure is: IPBPBIPBPBIPBPB …
The GOP structure IP can have any GOP length. The IPB structure must have a
GOP length that is a multiple of two. The IPBB structure has length that is a
multiple of three. The GOP structure I requires no GOP length.
Video stream type:
You can choose between the types VES (Video Elementary Stream) and PRG
(Program Stream). Select PRG if audio is to be transmitted together with the
video images. Audio signals require an additional bandwidth of about 256 kBit/s.
Note
Choosing VES results in no encoding of audio data.