Security-Center TV7203, Руководство по установке

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Administrator settings
Configuration / video
Best performance is produced by the maximum frame rate with best video quality and minimum network
bandwidth. The three factors “Max frame rate”, “Constant bit rate” and “Fixed quality” on the video
configuration page are interrelated.
Mobile access to the CMOS network camera
Many modern mobile telephones support access to MPEG4 videostream and GSM-AMR audio data. Due to
restricted bandwidth, only a maximum resolution of 176x144 pixels is supported. You should therefore select
“Configuration for mobile access”, and all necessary parameters are adjusted accordingly.
For high frame rates
To obtain a good visual realtime effect (more than 20 frames/s), the network bandwidth must be sufficiently
large. If the network bandwidth is higher than 1 Mbps, the value for the “Constant bit rate” must be set to
1000Kbps or 1200Kbps and the “Fixed quality” to the highest quality. In the PAL system, the maximum frame
rate is 25, and in the NTSC system, 30 frames per second. If your network bandwidth is more than 384Kbps,
you can fix the bit rate according to your bandwidth and the maximum frame rate to 25 or 30 fps (frames
per second). If the pictures in your environment are changed drastically, you can reduce the maximum frame
rate to 20 frames per second to set the data transmission rate lower. This gives you a better video quality,
and the human eye cannot distinguish between 20, 25 and 30 frames per second. If the network bandwidth
is less than 384 Kbps, adjust the “Constant bit rate” according to the bandwidth and try to get the best
performance by fine-tuning the “Max frame rate”. In a “slow” network, a high frame rate results in unclear,
distorted images. Another way to improve quality is to select “160x120” in the “Size” option, or “320x240”
for a larger view of the pictures. Video quality also depends on the number of users in the network.
Performance can also be affected by a bad connection and by a restriction of the network burst.