Axis Communications 221 - Manual (Page 54)

54 AXIS 221 - Technical Specifications
General performance considerations
When setting up your system, it is important to consider how various settings and
situations will affect performance. Some factors affect the amount of bandwidth (the bit
rate) required, others can affect the frame rate, and some will affect both. If the load on the
CPU reaches its maximum, this will also affect the frame rate.
The following factors are among the most important to consider:
• High image resolutions and/or lower compression levels result in larger images.
Bandwidth affected.
• Access by large numbers of Motion JPEG and/or unicast MPEG-4 clients. Band-
width affected.
• Simultaneous viewing of different streams (resolution, compression, etc.) by dif-
ferent clients. Frame rate and bandwidth affected.
• Accessing both Motion JPEG and MPEG-4 video streams simultaneously. Frame
rate and bandwidth affected.
• Heavy usage of event settings affects the camera’s CPU load. Frame rate affected.
• Enabled motion detection. Frame rate and bandwidth affected.
• Heavy network utilization due to poor infrastructure. Bandwidth affected
• Viewing on poorly performing client PC’s lowers perceived performance. Frame
rate affected.
Optimizing your system
To see the bandwidth and frame rate currenty required by the video stream, the AXIS 221
provides a tool that can be used to display these values directly in the video image.
To do this, special format strings are added as part
of a text overlay. Simply add #r (average frame
rate in fps) and/or #b (average bandwidth in kbps)
to the overlay.
For detailed instructions, please see the online
help for Video & Image > Overlay Settings, and
the help for File Naming & Date/Time Formats.
Important!
•The figures displayed here are the values as delivered by the camera. If other restrictions are
currently in force, (e.g. bandwidth limitation) these values might not correspond to those actu-
ally received by the client.
•For Motion JPEG, these values will only be accurate as long as no frame rate limit has been
specified.