Grass Valley PDR v.2.2 - Manual (Page 62)

Chapter 2 Using the Profile Configuration Manager
44 Profile Family
• Comb. Decoder mode tries to separate high frequency luminance from the
chrominance using the same notch filter as the notch decoder, but also takes
information from the next line. It uses this information to determine if high
frequency is luminance or chrominance. A comb decoder readily determines
finely spaced vertical lines are luminance. A lack of line to line phase
alteration causes difficulty with fine horizontal lines.
• Spatial Adaptive. Decoding uses either the comb or notch decoder, on a
pixel by pixel basis, depending on which gives the best results. For
horizontal lines, Notch is used; for vertical lines, Comb is used.
• Temporal/Spatial Adaptive. Decoding uses both the next line and the same
line in the alternate field in the calculations. This decoder uses all of the
properties of the Spatial Adaptive decoder, plus it uses Temporal (interfield
changes) information. The phase change (or lack of) from field to field helps
determine whether high frequency should be decoded as chrominance or
luminance.
NOTE: Spatial adaptive and temporal/spatial adaptive decoding use
the high or low threshold setting.
Temporal/Spatial Option
This control is only used if the Decode Mode is set to Temporal/Spatial
Adaptive. The threshold determines the amount of motion allowed between
alternate fields to still have the Temporal decoder recognize the pixel. High
allows more motion than Low.
Noise Reduction
These controls enable and set various noise reduction methods:
• Enable Luma and Chroma Reduction applies the Level and Threshold
settings to use a feedback noise reduction scheme on the decoded input
signals after they have been separated into chrominance and luminance. The
Level and Threshold settings determine the amount of weight the feedback
signal has in comparison to the input signal. The Threshold range takes into
consideration the amount of motion in the picture. Use the sliders to adjust
the ranges. Be sure Enable Luma and Chroma Reduction is checked for the
reduction values to be applied.