VPC 323xD, VPC 324xD
ADVANCE INFORMATION
2.3.8. PAL Compensation/1-H Comb Filter
CVBS
Luma
Y
Y
Notch
filter
The color decoder uses one fully integrated delay line.
Only active video is stored.
8
8
chroma
Chroma
Process.
Chroma
C C
C C
r
r
b
b
Process.
8
The delay line application depends on the color stan-
dard:
a) conventional
b) S-VHS
– NTSC:
– PAL:
1-H comb filter or color compensation
CVBS
Y
Notch
filter
color compensation
8
– SECAM: crossover-switch
1 H
Chroma
C C
r
b
Delay
Process.
In the NTSC compensated mode, Fig. 2–6 c), the color
signal is averaged for two adjacent lines. Thus,
cross-color distortion and chroma noise is reduced. In
the NTSC 1-H comb filter mode, Fig. 2–6 d), the delay
line is in the composite signal path, thus allowing
reduction of cross-color components, as well as
cross-luminance. The loss of vertical resolution in the
luminance channel is compensated by adding the ver-
tical detail signal with removed color information. If the
4H adaptive comb filter is used, the 1-H NTSC comb
filter has to be deselected.
c) compensated
Notch
filter
Y
CVBS
1 H
Delay
8
C C
r
b
Chroma
Process.
d) comb filter
Fig. 2–6: NTSC color decoding options
CVBS
Y
Notch
filter
8
1 H
Delay
Chroma
Process.
C C
r
b
a) conventional
Luma
Y
8
Chroma
1 H
Chroma
Process.
C C
r
b
Delay
8
b) S-VHS
Fig. 2–7: PAL color decoding options
CVBS
Y
Notch
filter
8
MUX
1 H
Delay
Chroma
Process.
C C
r
b
Fig. 2–8: SECAM color decoding
12
Micronas
MICRONAS [ MICRONAS ]
