Version: 20210708
9
The total streaming capacity is obtained by adding the load of all unique streams. Only unique streams are counted
for as requesting twice the same video stream (same resolution, frame rate, encoding type, compression, etc.) from
a camera does not require separate encoding and as such does not increase the computational requirements.
P
CPU
= Σ unique P
stream
Araani fire detection analytics requires a stream of 1920 x 1080 at 12 frames per second, thus:
P
Araani
= 1920 x 1080 x 12 = 24,9 mps
This stream should be considered when calculating the total load.
The streaming load is practically independent of the encoding type (H264 versus H265).
The maximum capacity for a camera depends on the type of processor. Currently, two generations of processor are
common in the Axis offering, named ARTPEC-6 and ARTPEC-7. These are the limits for both processor types:
•
ARTPEC-6 maximum total streaming capacity = approximately 310 mps.
•
ARTPEC-7 maximum total streaming capacity = approximately 367 mps.
In case of doubt, contact your supplier to know what processor type is used in your cameras.
As video stream compression is occurring in a dedicated part of the CPU, these limits are practically independent of
other processor activities such as image optimization, mirroring or ACAP-based analytics.
For proper functioning of Araani fire detection analytics, make sure the total stream demand - including the required
analytics stream - does not exceed this limit and preferably add some margin. If that limit is exceeded, the camera
will lower the frame rate on ALL streams and as a result, Araani analytics will no longer work.
Example
: A 4K CCTV system requires one high resolution stream for visualization and one HD resolution stream for
recording.
Stream role
Resolution
P
stream
Visualization
3840 x 2160 @ 25 fps
207,4 mps
Recording
1920 x 1080 @ 25 fps
51,8 mps
Araani analytics
1920 x 1080 @ 12 fps
24,9 mps
Total
284,1 mps
The total load in this example is well below the limit of both processor types, so this will work fine. Adding another
HD recording stream with different settings for example would exceed the maximum performance of an ARTPEC-6
based camera and analytics will fail to run on such combination.
LENS REQUIREMENTS
Selection of the lens depends on:
•
Field of view to cover. Most lenses today are multifocal, allowing adaptation at installation time to fit the
environment. Online lens calculators can help to select the proper focal range.
•
Area of risk.
•
Light conditions: day / night / seasons.
•
Light stability / light changes.
•
Uniformity of illumination.
•
Interchangeable lens.
•
Etc.
Consult with your camera supplier for proper selection of the lens type and specifications.
