ADS Technologies USBAV-708 INSTANT VIDEOMPX, User Manual

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type <Frame_type>
Frame_type is the type of each frame and can be one of ‘I’,’P’ or ‘B’,
representing intra-frame, predicted frame or bi-directional frame
respectively.
total_bits <Value>
Value is the total number of bits used by the encoder to encode the
frame.
motion_complexity <Value>
Value is a floating point number proportional to the number of bits
required to encode all motion data in the frame.
This will be zero only for intra-frames.
texture_complexity <Value>
Value is a floating point number proportional to the number of bits
required to encode the texture in the frame.
For intra-frames the value is associated with the bits required to
encode the image. For predicted and bi-directional frames the value
is associated with the bits required to encode the residual (difference
between source and motion-compensated frames).
modulation <Value>
Value is a floating point number representing the modulation value
set by the EKG application between passes.
Modulation acts as a co-efficient to the frame quantizer selected by
the rate control algorithm. By raising the modulation value for a frame
above one the quantizer will be increased resulting in lower quality
for that frame. Conversely, lowering the value below one will cause
the quantizer to be reduced thus raising the quality for the frame.
As an example, if the rate control were to determine quantizer 2
should be used but the modulation for the frame was 1.5 the result
would be a quantizer of 2 x 1.5 = 3.
Modulation should not be confused with the
Bitrate modulation option
in the encoder configuration dialogue which is not directly related.