Comrex LiveShot Portable, Manual

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2 Low Latency - Latency is considered to be an overriding factor over quality in this
mode. Use only in environments where the lowest possible latency is important.
For most users, the amount of latency reduced in this mode is a poor tradeoff for
quality.
3 Constrained Bitrate - This mode limits the “burstiness” of the encoder to 1.5x the
target bitrate over a one second window. It’s useful for networks that perform
poorly when bursty data is applied.
Scene Complexity Detection - In an effort to avoid artifacts when sending video with many constant
scene changes (like edited video), LiveShot can reduce the overall quality slightly in order to better
compensate for these changes. Normally disabled.
Digital Noise Reduction (DNR) - At low bitrates, it can sometimes be helpful to apply a filter to “ soften ”
the video image. This can be perceived as the image being “ cleaner ” with less “ digital noise ”. This
option is available but off by default.
GOP Structure - This option determines the number of B-frames sent by the H.264 encoder. Use of
B frames can increase performance in instances of high motion and high detail, but increases delay
because a buffer must be added to the process. Default is not to use B frames, but if your video quality
is critical and delay is not a concern, adding one, two or three B frame sequences to the encoder can
improve the image.
Keyframe Interval - In H.264 video coding, reference frames are sent periodically to reset the
predictions made by the encoder algorithm. This results in most errors being corrected, and overall
artifacts reduced when this “
Keyframe ” is processed. This option determines how often the keyframe
is sent. Default is 1 second. Lowering this can provide error resilience at the cost of quality and
bandwidth. Raising it can lower bandwidth but reduce error resilience. When
Intra-refresh mode is
enabled, this will affect the cadence of the “ rolling bar ” artifact.
Buffer Parameters - These options are common for all types of streams, so they are treated in their
own separate section below.
Stream Optional - This option determines whether a connection will fail in the absence of a source
for this particular stream. For example, if a video input is left unconnected, but a stream is defined to
use it, the system can be set to fail or complete the connection anyway. For bidirectional streams, it’s
possible to set one or the other direction to
optional individually.