VBrick dme, Admin Manual

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Output Stream Configuration
DME Admin Guide 131
Seconds per Segment The number of seconds for which a media segment is created. Range
1–600. Default = 8. By increasing this number you will increase the
initial time it takes to play the HLS stream. Since a separate HTTP
access is required for each segment, Performance is optimized by
keeping this number larger. Since a separate HTTP access is required
for each segment, performance is improved by keeping this number
larger. For best results, this number should always be a multiple of
the IDR Frame Interval on the encoder. For example, if the IDR
Frame Interval is 4, this value should be 8, 12, 16 and so forth.
Latency Tuning for HLS/HDS
Latency is a common concern when delivering live content across
HLS or HDS. Latency can be tuned up or down and will impact
server load.
The Minimum Segment Length (MSL) field, as defined above, has a
big impact on latency. The system needs 3 segments to build a
playlist (even if the playlist length is greater than 3). Once that
playlist is created, players can retrieve it and begin playing. Therefore,
with the current default of an 8 second segment length, it takes 24
seconds before a playlist is created. This introduces 24 seconds of
latency. Lowering the MSL reduces latency by reducing the time to
generate the playlist; however, it creates a larger resource need on the
server. Smaller segments mean an increased number of HTTP
requests from players for more segments and playlists. It is also
important to reiterate, as noted above, if you reduce your MSL to
make sure that it is a multiple of the IDR Frame Interval from the
encoder.
Automatic Detection Automatic Detection will evaluate the stream and provide optimized
Segment Size. For example, if you set your encode to have 2 seconds
between keyframes (note: this is the recommended setting), then by
selecting this option the DME will automatically create optimized
HLS segments and reduce the HLS introduced latency.
Enable Enable or disable the stream. Note that if HLS is streaming and is
then disabled, it may take several minutes for HLS to mark that input
stream as disconnected / not found.
Status Disabled | Waiting | Active
URL This will display the URL for the master playlist. Use this URL for
testing and/or distributing to viewers.
Field Description