Operation Manual

Niagara 9100 Series User Guide
ViewCast 207
Setting
Explanation
number to smooth out low bit rate video encodes. In general,
values lower than -3 and higher than 3 are usually not used,
but could be if so desired.
LookaheadFrames
This value is the amount of frames the encoder keeps in its
buffers to perform various calculations. The higher this value,
the better the quality and the closer to a constant bit rate the
encoded video will be; however the CPU load is higher and
the latency from the source through the encoder is also
higher. Setting this to 0, depending on the encoder, will
provide the lowest latency possible.
NoiseReduction
This value performs adaptive noise reduction, estimates film
noise based on the value and attempts to remove the noise
by dropping small details before quantization (100 to 1000 for
de-noising). As a result, using Noise Reduction can make the
encoded video look smoother, but with much less detail.
QuantizerMax
This value sets the maximum for the quantizer. The range is 1
to 51 with 51 being the highest and least complex quantizer
available. The value 51 provides the most encoding, thus
making the picture quality farthest away from the original.
However, lowering this value increases CPU load, in some
cases considerably. Also, this value affects the bit rate with 51
keeping closer to a constant bit rate, while lower values cause
the bit rate to vary.
QuantizerMin
This value sets the minimum quantizer ever used in the
encoder. The lower the quantizer, the closer the encoded
video is to the original. For most video, any value below 10
appears almost the same as the original video.
ReferenceFrames
This value is the number of previous frames each P-frame can
use as a reference. More reference frames increase the
quality of the encoded video but increases the CPU load. Each
increase, however has reduced benefit and takes longer to
encode.
SceneChangeDetectThreshold
Higher values of this setting cause the encoder to detect
more scene changes. For example, a fast action movie that
has many scenes can have this value set lower than a
newscast, but the newscast video quality may suffer a bit at
the same value. 60 is a good default for most applications. 0
turns off scene change detection, but this is not
recommended. Higher values also increase CPU usage.
TrellisRDQuantization
This value performs Trellis quantization to increase the visual
quality of the encoded video: the higher the value, the better
the qualities of the video, but the higher the CPU load. This
value can also improve visual quality at lower bit rates.
However, settings above 0 are applicable for Main or High
Profile in the Custom Presets.