GE Legend IP, Руководство пользователя

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Chapter 5
Advanced programming
57
Video resolution, bit rate, and frame rate are determined by the quality setting you choose. The greyed
out drop down boxes are there to tell you what the settings are for each quality setting, and they are not
changeable by the user.
When viewing video over a network, a lower frame rate translates into what appears to be higher
latency. For example, at 30fps, you see a new image every 30th of a second. At 5fps, you see a new
frame every 5th of a second, or six times as long compared to 30fps. This delay in new images can
mean difficulty controlling the unit because the screen updates at a slower rate.
Variable bit rate. You can choose a percentage that will allow the bit rate to vary by that amount based on
the complexity of the video being transmitted.
Preset. This allows you to choose the level of latency you prefer. If you choose low latency, the image
quality will be slightly reduced to decrease latency. If you choose normal, latency is balance with the
quality of the image.
D1 medium-low 7fps 600
D1 low 5fps 300
D1 very-low 3fps 150
2CIF full 30fps 1500
2CIF high 15fps 600
2CIF medium 10fps 450
2CIF medium-low 7fps 300
2CIF low 5fps 150
CIF full 30 fps 600
CIF high 15fps 300
CIF medium 10fps 200
CIF medium-low 7fps 150
Table 8. Quality settings and data rates
Quality setting Bandwidth requirements (kbps)