Cobalt Digital COMPASS 9223 Dual-Channel 3G_HD_SD MPEG-4 Encoder - Manual (Page 48)

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9223-OM (V2.0)
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Server Location: Select Local to use the local server in the device itself.
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Segment (sec): Number of seconds per segment. This defines the approximate size (in
seconds) for the above bitstream encoded files. The valid range is from 1 to 20 seconds.
Note that the clients will experience latency approximately equal to the segment size
times the number of segments. Given the limited amount of memory storage in the local
encoder server, at higher bit rates the segment size will be limited. The 9223 has
20 Mbytes of storage per encoder.
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Number of Segments: This defines the number of bitstream segments advertised in the
playlist. The minimum number, as per the HLS specification, is 3. Some set-top boxes
require 4 segments. Apple devices (iPads, iPods, etc.) work well with 3 segments.
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Program Name: This program name is placed in the playlist file. Whether or not it is
shown depends on the client. This is an optional parameter. If entered, it will be shown
as part of the encoder link in the web page generated by the 9223.
In local server mode, the access URLs for the content are:
http://xxx.xxx.xxx.xxx/HLS/encoder1.m3u8
http://xxx.xxx.xxx.xxx/HLS/encoder2.m3u8
where xxx.xxx.xxx.xxx is the IP Address of the 9223 Ethernet port. In the 9223, HLS
streams are available through both streaming Ethernet ports. In the 9223-SA version, in addition
to the streaming Ethernet ports, HLS content can also be accessed from the control port. Also
note that if you use a browser to go to the encoder IP address (i.e., just go to
http://xxx.xxx.xxx.xxx ), there will be a link for the HLS page.
HLS Implementation Notes
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When HTTP Live Streaming is selected, the GOP Mode control is set to Closed GOP
and is not selectable. This is done to ensure that each segment is self-contained.
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The maximum video bit rate allowed in HLS mode is 15 Mb/s.
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The maximum aggregate performance of the built-in HLS server in the 9223 is between
20 and 30 Mb/s (total bit rate to all clients), and is somewhat dependent on network
conditions. The built-in server is intended to serve only a small handful of clients and