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ADV7181B
PAL Comb Filter Settings
Used for PAL-B/G/H/I/D, PAL-M, PAL-Combinational N,
PAL-60, and NTSC443 CVBS inputs.
Rev. 0 | Page 35 of 96
PSFSEL[1:0] Split Filter Selection PAL, Address 0x19 [1:0]
The NSFSEL[1:0] control selects how much of the overall signal
bandwidth is fed to the combs. A wide split filter selection
eliminates dot crawl, but shows imperfections on diagonal lines.
The opposite is true for selecting a narrow bandwidth split filter.
Table 46. PSFSEL Function
PSFSEL[1:0]
00
01 (default)
10
11
Description
Narrow
Medium
Wide
Widest
CTAPSP[1:0] Chroma Comb Taps PAL, Address 0x39 [7:6]
Table 47. CTAPSP Function
CTAPSP[1:0]
00
01
Description
Do not use.
PAL chroma comb adapts 5 lines (3 taps) to
3 lines (2 taps); cancels cross luma only.
PAL chroma comb adapts 5 lines (5 taps) to
3 lines (3 taps); cancels cross luma and hue error less well.
PAL chroma comb adapts 5 lines (5 taps) to
4 lines (4 taps); cancels cross luma and hue error well.
10
11 (default)
CCMP[2:0] Chroma Comb Mode PAL, Address 0x39 [5:3]
Table 48. CCMP Function
CCMP[2:0]
Description
0xx (default)
Adaptive comb mode.
Configuration
Adaptive 3-line chroma comb for CTAPSP = 01.
Adaptive 4-line chroma comb for CTAPSP = 10.
Adaptive 5-line chroma comb for CTAPSP = 11.
Fixed 2-line chroma comb for CTAPSP = 01.
Fixed 3-line chroma comb for CTAPSP = 10.
Fixed 4-line chroma comb for CTAPSP = 11.
Fixed 3-line chroma comb for CTAPSP = 01.
Fixed 4-line chroma comb for CTAPSP = 10.
Fixed 5-line chroma comb for CTAPSP = 11.
Fixed 2-line chroma comb for CTAPSP = 01.
Fixed 3-line chroma comb for CTAPSP = 10.
Fixed 4-line chroma comb for CTAPSP = 11.
100
101
Disable chroma comb.
Fixed chroma comb (top lines of line memory).
110
Fixed chroma comb (all lines of line memory).
111
Fixed chroma comb (bottom lines of line memory).
YCMP[2:0] Luma Comb Mode PAL, Address 0x39 [2:0]
Table 49. YCMP Function
YCMP[2:0]
Description
0xx (default)
Adaptive comb mode.
100
Disable luma comb.
101
Fixed luma comb (top lines of line memory).
110
Fixed luma comb (all lines of line memory).
111
Fixed luma comb (bottom lines of line memory).
Configuration
Adaptive 5 lines (3 taps) luma comb.
Use low-pass/notch filter; see the Y Shaping Filter section.
Fixed 3 lines (2 taps) luma comb.
Fixed 5 lines (3 taps) luma comb.
Fixed 3 lines (2 taps) luma comb.