audio. Due to the limitation of the bandwidth for 3GPP, only 176x144 video solution will be supported for cell phone viewing. Select the “Configure for mobile viewing” option will change the range of other related video settings.

For Best Real-time Video Images

To achieve good real-time visual effect, the network bandwidth should be large enough to allow a transmission rate of greater than 20 image frames per second. If the broadband network is over 1 Mbps, set the “Fix bit rate” to 1000Kbps or 1200Kbps, and set “Fix quality” at the highest quality. The maximum frame rate is 30. If your network bandwidth is more than 512Kbps, you can fix the bit rate according to your bandwidth and set the maximum frame rate to 30 fps. If the images vary dramatically in your environment, you may want to slow the maximum frame rate down to 20 fps in order to lower the rate of data transmission. This allows for better video quality and the human eyes cannot readily detect the differences between those of 20, 25, or 30 frames per second. If your network bandwidth is below 512 Kbps, set the “Fix bit rate” according to your bandwidth and try to get the best performance by fine-tuning with the “Maximum frame rate”. In a slow network, greater frame rate results in blur images. Another work-around is to choose “160x120” in the “Size” option for better images. Video quality performance will vary somewhat due to the number of users viewing on the network; even when the parameters have initially been finely tuned. Performance will also suffer due to poor connectivity because of the network’s burst constraint.

Only Quality Images Will Do

To have the best video quality, you should set “Fix quality” at “Detailed” or “Excellent” and adjust the “Maximum frame rate” to match your network’s bandwidth. If your network is slow and you receive “broken” pictures, go to the TCP protocol in “Connection type” and choose a more appropriate mode of transmission. The images may suffer a time delay due to a slower connection. The delay will also increase with added number of users.

Somewhere Between Real-time and Clear Images

If you have a broadband network, set “Fix quality” at ”Normal” or better, rather than setting “Fix bit rate”. You can also fix the bandwidth according to your actual network

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Vivotek IP7137 manual For Best Real-time Video Images