W O W Z A N D V R 4 U S E R ' S G U I D E
Copyright © 2007
–2015 Wowza Media Systems™, LLC. All rights reserved.
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Configuration notes
Align audio and video
Wowza nDVR expects incoming audio and video to be aligned. It relies on timecode
information to create chunks where video key frames occur. If audio and video become
unaligned, nDVR tries to compensate for this problem, but it can't always resolve it.
Alignment issues start before nDVR starts recording. They begin in the encoding process or
originate as an issue with the live source. Typically, you can modify the encoder settings to
address the issue. You should fix audio and video alignment issues upstream from the
Wowza Streaming Engine server.
If alignment issues are pronounced, nDVR discards chunks and unexpected behavior can
occur in time-based custom configurations. nDVR will log messages to alert you to alignment
issues while recording. If the alignment problem can't be fixed at the source or encoder, you
can use the
dvrPacketSortTime
property to add a packet sorter before the audio and video
packets get to nDVR. Note that this property adds additional latency equal to its value. For
more information about this and other properties, see
How to do advanced configuration for
Wowza nDVR
.
Configure live stream repeater (origin/edge)
Wowza nDVR supports origin/edge configuration. For more information, see
How to set up
live stream repeater for use with Wowza nDVR (origin/edge)
.
Optimize for performance
Wowza nDVR performance is dependent on disk I/O; therefore, a fast disk is critical for best
performance.
Customize recordings
How to customize your recording, how to enable Wowza nDVR, and the required Wowza
nDVR configuration are described in
How to set-up and run Wowza nDVR for live streaming
.
Properties for advanced configuration are described in
How to do advanced configuration for
Wowza nDVR
.
We recommend that you start with the default
append
archive strategy and test with your
live stream before making advanced customizations.
Summary of Contents for nDVR
Page 1: ...Wowza nDVR User s Guide ...