Axis Communications 241S Manuel D’Utilisation

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AXIS 241S/241Q - 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 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 currently required by the video stream, the AXIS 
241S/241Q 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) 
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 server. If other restrictions are 
 
currently in force, (e.g. bandwidth limitation) these values might not correspond to those 
 
actually received by the client.
•For Motion JPEG, these values will only be accurate as long as no frame rate limit has been 
specified.