2. Product information
6.
Auto pro
fi
le
By default, the NGS-D320 encoder pro
fi
le is set to “auto”.
In this option, the device will automatically select a pro
fi
le based on the input resolution it detects.
The table shows the auto-selected pro
fi
le:
Resolution
Pro
fi
le
<= 1920x1200
main_8m_2mp_60
> 1920x1200 and <= 2560x1600
high_12m_4mp_30
> 2560x1600
high_12m_8mp_15
7.
GDR pro
fi
le
GDR stands for “Gradual Decoder Refresh”. This is a pro
fi
le that does not generate I-frames, in order
to optimize bandwidth & latency.
The main drawbacks are that not all H.264 decoders can handle GDR pro
fi
les and that switching time
at the decoder could increase, as there is no I-frame in the stream to sync switching to.
If the NGS-D320 encoder is used with any other H.264 decoder, you can select a GDR pro
fi
le and
attempt to decode it, but if the decoder behavior is unreliable, it is recommended to select a non GDR
pro
fi
le.
The NGS-D320 decoder can handle GDR pro
fi
les, and in an NGS-D320 encoder/NGS-D320 decoder
setup, we recommend to con
fi
gure the encoder to a GDR pro
fi
le, to achieve optimal latency perfor-
mance.
The NGS-D320 supports GDR for a number of H.264 encoder pro
fi
les. Refer to "Settings", page 32
on how to con
fi
gure.
8.
Source downscaling
The selected pro
fi
le may result in downscaling of the input source resolution to the maximum resolution
supported by this pro
fi
le.
The below table shows an example:
Input
Pro
fi
le
Stream out
main_4m_
2mp
_60
H.264 stream 60Hz,
1920x1200
main_4m_4mp_
30
H.264 stream
30Hz
, 2560x1600
2560x1600p60
base_512_
1mp
_60
H.264 stream 60Hz,
1280x800
Pro
fi
le naming: The gdr extension only applies to a limited number of pro
fi
les. See also
the explanation on the GDR pro
fi
le.
Decoding
When an NGS-D320 is setup to encode H.264 streams, these streams can be decoded either in hardware
(e.g. on another NGS-D320) or in software (on a standard PC).
1.
Hardware
The NGS-D320 supports H.264 hardware decoding.
The Lite and Pro model limitations apply similar to decoding as to encoding.
The device can not just decode
any
H.264 stream on the network, it can only decode H.264 streams
generated by another NGS-D320.
Do not attempt to decode H.264 streams from other sources, as this could lead to unreliable behavior,
e.g. from artifacts in the image, to no image at all.
For setting up hardware decoding, refer to "Decoder settings", page 38.
2.
Software
The NGS-D320 video and audio streams can be software decoded on a standard PC using applica-
tions like VLC, Quicktime, Media Player, …
Performance of the decoding is dependent on the combination of the H.264 stream pro
fi
le and the PC
speci
fi
cations.
14
K5903129 NGS-D320 29/09/2016
