epiphan Networked VGA Grid, User Manual

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Networked VGA Grid User Guide Configure encoding (HD Encoder channels)
factors, for example:
l
overall system load affects the ability for the device to process
pixels;
l
available network bandwidth;
l
the source and stream frame size (resolution);
l
the type of motion that is captured; and
l
number of users accessing the stream.
When adjusting the frame rate, you may need to try different values to
achieve the best outcome. The following table provides the performance
expectations when typical settings are used.
Table 27 Performance expectations
Setting H.264 MPEG
Resolution 1920×1200 1920×1080
Video encoding
preset: Quality
25-26 fps 13 fps
Video Encoding
preset: Speed
27-28 fps 17-18 fps
Bitrate
In general, higher bitrate mean higher image quality in the stream, at the
cost of higher bandwidth needed to transmit it.
For comparison against something you are likely familiar with, an HD Blu-
ray video is typically in the range of 20 mbps, standard-definition DVD is
usually 6 mbps.
If you don't know what value to use, a good place to start is 5000 kbps
(slightly less than a typical DVD). Test to see how this works for your
viewers and adjust.
Configure audio codec
If your VGA Grid HD Encoder has an attached audio source your stream will by default use the AAC audio
codec at 48 kHz. You can modify this setting to best match your streaming or post-processing needs.
To configure your stream's audio codec complete these steps in the VGA Grid's Admin panel:
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