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AXIS 247S - Technical Specifications

Frame rates - MPEG-4

The following test results show the frame rates in frames/second (fps) for MPEG-4 streams from the Video

Server. Note that these values are guidelines only - actual values may vary.

The MPEG-4 test conditions:

• Compression level = 50%

• Video Object Type = Advanced Simple

• GOV structure = IP*

*Note that setting the GOV structure to use “I-frames only” will increase the frame rate.

Bandwidth

As there are many factors affecting bandwidth, it is very difficult to predict the required amounts. The settings

that affect bandwidth are:

• the image resolution

• the image compression

•the frame rate

• the MPEG-4 object type

• the MPEG-4 GOV structure

• the analog cameras connected to the Video Server

• the audio settings

There are also factors in the monitored scene that will affect the bandwidth. These are:

• the amount of motion

• the image’s complexity

• the lighting conditions.

For MPEG-4, if there is only limited bandwidth available, and if this is more important than the image quality,

using a constant bit rate (CBR) is recommended. Use a variable bit rate (VBR) if the image quality needs to be

maintained at a higher level. If supported on the network, consider also using MPEG-4 multicasting, as the

bandwidth consumption will be much lower.

Resolution fps (NTSC/PAL)

4CIF 27/23

VGA 30/25

2CIF 30/25

CIF 30/25

QVGA 30/25

QCIF 30/25

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Axis 247S Manuel d'utilisateur Page 40