Z3 Technology Z3-DM368-RPS, Руководство пользователя

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CONFIDENTIAL DOC-USR-0049-03
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7.11 Adjusting for Latency and Quality
For latency, the key parameter to work with is Video Burst Size.
Video Burst Size defines the number of milliseconds of buffering the encoder has to work with. The
higher this value, the more buffers it has to work with and the more time it has to “smooth things out”
for challenging content. However, a higher value also causes latency to increase accordingly. To
minimize latency, this value should be set to the lowest possible value. The lowest value Z3
recommends is 150.
Figure 18
shows the suggested values for Video Burst Size and B-frame Interval for 3 common use cases:
Video Burst Size
Case 1: Highest Quality, Highest Latency 2000
Case 2: Good Quality, Standard Latency 1000
Case 3: Normal Quality, Lowest Latency 150
RTP offers lower latency than UDP, so for the lowest latency you should use RTP.
If you are streaming to VLC, you can reduce latency on the decode side by adjusting the network caching
value. By default, this is set to 1000ms. You can lower this to as low as 200ms. To do this, go to the
following:
VLC
→
Tools
→
Preferences
→
Show Settings (ALL)
→
Input / Codecs
→
Network caching (ms)
Figure 18 Tuning for Various Use Cases