CPP100
SECTION 6
CPP1OPS
25/10/06
www.snellwilcox.com
Version 1 Issue 6
6.32
Comb
This selects the style of Combing and adaptive
algorithms
Adaptive
Adaptive Field comb
Normal
Non-Adaptive Field comb
Default
Adaptive
There are two modes of YC separation using
different combing architectures. Each mode has
been optimised for different applications.
Adaptive mode
This mode uses a field comb to separate Y &
C. Traditional comb failure artefacts are
suppressed by a tailored algorithm. This
mode should be used if failure artefacts
become obtrusive or if minimum
chrominance smear on shot changes is
required.
Normal mode
This mode uses a non-adaptive field comb to
separate Y & C. This mode gives the best
possible YC separation giving a high
luminance bandwidth and significantly
reduced cross colour. However, some comb
failure artefacts will be noticed on saturated
vertical transitions.
‘Golden Gate’ Option
The ‘Golden gate’ option allows one of nine
types of comb filtering systems to be applied
to the signal.
Studio 1 This mode should be used for ‘real
life’ type pictures (sports etc). This
mode should be used as a starting
point.
L
Disk
In this mode the timebase
correction and decoding are
optimised to give maximum
performance from LaserDisk
sources
VHS
In this mode the timebase
correction and decoding modes are
optimised to give maximum
performance from VHS and other
non-mathematical signal sources.
Studio 2 This mode should be used for
‘non-sport’ type materials.
Mindel
(not on –G version)
This mode produces the minimum
input/output delay (approx. 3 lines)
and may be used where audio
delay problems may exist and
cannot be compensated for.
Still
This mode gives the best results
with sources that contain no
motion. e.g. Rostrum cameras
and still graphics.
Simple 1 This simple decode mode
incorporates a wide bandwidth
subcarrier notch filter.
Simple 2 This simple decode mode
incorporates a narrow bandwidth
subcarrier notch filter.
Line
This is a classical line comb with
no adaption.
Vert Adap
(not on –G version)
This disables or enables the Adaptive algorithm for
the vertical filter.
On
Adaptive filtering
Off
Vertical filtering, ie. No Adaption
Default
Off
Hannover bars and small chroma phase errors are
suppressed by averaging across adjacent lines. An
adaptive vertical filter has been included which
cancels out small chrominance phase errors thus
suppressing Hannover bars.
The operation will generally depend upon the type
of material being decoded. Some guidelines as to
which settings should be used are given below.
