8.Features
© 2023 China Daheng Group, Inc. Beijing Image Vision Technology Branch 123
T
data
=
(
1500×8
)
10,000,000,000
⁄
=1.2us
The effective network bandwidth is:
BandW
avial
=(1464×8×(1-0.2))/(1.2us+1us)=4259Mbps
Note: Each stream packet contains 36 bytes of network header data, and a packet with the size of 1500
bytes contains only 1464 bytes of valid data.
Example 2: The packet size is 8192, the packet delay is 2000, the reserved bandwidth is 20%, and the
link speed is 10Gbps.
The time to transport a single stream packet is:
T
data
=
(
8192×8
)
10,000,000,000
⁄
=6.5us
The effective network bandwidth is:
BandW
avial
=(8156×8×(1-0.2))/(6.5us+2us)=6141Mbps
1)
The packet delay time cannot be greater than the packet timeout and the block timeout.
2)
The packet delay time should be less than the packet t 20(ms).
3)
The packet delay time should be less than the block t 20(ms).
8.5.4.
Bandwidth Reserve
The Bandwidth Reserve is used to reserve a part of bandwidth for packet retransmission and control data
transfer between the camera and the host, and can be used for multiple cameras transmission, to limit the
bandwidth allocation of each camera. For example, the network bandwidth is 10Gbps, setting the reserved
bandwidth value to 2%, then the bandwidth will be reserved to 0.2Gbps. When the maximum bandwidth
required for transmission is greater than the current bandwidth available, the camera reduces the frame
rate to ensure the stability of the transmission.
8.6.
Events
When event notification is set to “on”, the camera can generate an “event” and transmit a related event
message to the host whenever a specific situation has occurred. For MRAS-GT camera, the camera can
generate and transmit events for the following situations:
The camera has ended exposure (ExposureEnd)
An image block is discarded (BlockDiscard)
The trigger signal overflow (FrameStartOvertrigger)
The image frame block is not empty (BlockNotEmpty)
The event queue is overflow (EventOverrun)
Every event has a corresponding enable status, and in default all the events’ enable status are disable.
