AK8858 Datasheet, PDF (53/96 Pages) Asahi Kasei Microsystems – PS/SD Multi Format Video Decoder

[AK8858]
[7.28] Color killer
In CVBS or S-video input, the chroma signal quality of the input signal is determined by comparison of its color
burst level against the threshold setting in the color killer control register. If the level is below the threshold, the
color killer is activated, resulting in processing of the input as a monochrome signal and thus with CbCr data
fixed at 0x80. Depending on the register setting, the color killer may also be activated by failure of the color
decode PLL lock.
Settings for color killer ON and OFF
COLKILL-bit
0
1
Enable
Disable
Sub Address: 0x11 [7]
Notes
Settings for color killer activation
CKILSEL-bit
Condition for activation
0
Burst level below threshold setting in CKLVL[3:0]-bits
1
Burst level below threshold setting in CKLVL[3:0]-bits, or
Failure of color decode PLL lock
Sub Address: 0x11 [6]
Notes
For threshold setting
Name
CKLVL0
~
CKLVL3
Definition
[CKLVL3 : CKLVL0 ]
[0000]: −29.7dB
[0001]: −28.4dB
[0010]: −27.2dB
[0011]: −26.2dB
[0100]: −25.3dB
[0101]: −24.5dB
[0110]: −23.7dB
[0111]: −23.0dB
[1000]: −22.4dB (Default)
[1001]: −21.8dB
[1010]: −21.2dB
[1011]: −20.7dB
[1100]: −20.2dB
[1101]: −19.7dB
[1110]: −19.3dB
[1111]: −18.9dB
Sub Address: 0x11 [3:0]
Used for threshold setting with SECAM input.
Name
Definition
CKSCM0
~
CKSCM1
[CKSCM1 : CKSCM0 ]
[00]: {CKLVL[3:0]}
[01]: {0, CKLVL[3:1]} (1bit shift)
[10]: {0, 0, CKLVL[3:2]} (2bit shift)
[11]: Reserved
Sub Address: 0x11 [5:4]
MS1230-E-00
- 53 -
2010/9