Impact Of Compression; Impact Of Number Of Video Streams - American Dynamics VideoEdge Design Manual

Example of Field-of-View Comparison Between Different Resolutions

Impact of Compression

Another parameter to consider is the level of compression that is selected for the device. Each device will
support a different number of compression levels. At lower compression levels, the output will be greater in
size. To reduce the bandwidth, higher compression levels can be used, but the resulting image will be
more pixilated as less information is being retained for each frame. Selection of compression will generally
be dependent video quality. The VideoEdge NVR provides the ability to select the level of compression
that is supported by each device.

Impact of Number of Video Streams

The final impact on network traffic will be the total number of simultaneous video streams. The current
version of VideoEdge NVMS supports single streams for each device and unicast. This impact must be
split into two parts:
• Video Input: Number of streams that can be received by the VideoEdge NVR (e.g. LAN2 traffic from
IP cameras and encoders)
VideoEdge NVR can support as little as one video channel or as many as 128 video channels. The
total number of video streams supported will be directly dependent on a few key factors: server
hardware performance, storage performance, video recording mode, camera data rates (settings
for video codec, resolution, frame rate), and available network bandwidth.
• Video Output: Number of streams being sent out from the VideoEdge NVR (e.g. LAN1 traffic to
clients)
Transcoding does not occur on the VideoEdge NVR, therefore the server will reflect the incoming
video out to the number of requests being received. The total number of output streams
VideoEdge NVR can support as little as one stream or as many streams which can be sent over
the available bandwidth on the LAN1 Gigabit port.
Due to all of the possible setting combinations for each individual video device, we have taken 4CIF @ 30
fps as our baseline to confirm maximum performance on the VideoEdge NVR Bundled Server platform.
The test data compiled based on this setting supports up to 64 cameras with continuous recording on all
cameras or 32 cameras with motion detection recording on all cameras.
VideoEdge NVMS Design Guide
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