AK8856VN Datasheet, PDF (29/98 Pages) Asahi Kasei Microsystems – NTSC/PAL Video Decoder

ASAHI KASEI
[AK8856VN]
(2) Brightness
Brightness is adjusted by adding a value which is set by Brightness Control Register (R/W) [Sub Address
0x07] to the luminance (Y) signal.
YOUT = YIN + BR
YOUT : brightness arithmetic operation result
YIN : before brightness arithmetic operation
BR : brightness coefficient (register value)
The brightness coefficient varies from –127 to +127, and the value is in 2’s complement format. When the
arithmetic operation result exceeds this range, it is clamped to the upper-limit of 254 or the lower-limit of 1
(output result ranges from 16 to 235 when the 601 limit-bit is 1).
Bit allocation of Brightness Control Register:
Sub Address 0x07
bit 7
bit 6
BR7
BR6
0
0
bit 5
BR5
0
bit 4
bit 3
BR4
BR3
Default Value
0
0
bit 2
BR2
0
Default Value: 0x00
bit 1
bit 0
BR1
BR0
0
0
(3) Color Saturation
Color Saturation is adjusted by multiplying the Color Signal (C) by a value which is set by the Saturation
Control Register (R/W) [Sub Address 0x08]. The arithmetic result is U / V de-modulated. The Saturation
coefficient varies from 0 to 255 in 1/128 programmable steps. The default value of the register is a non-
adjusted value (0x80).
Bit allocation of Saturation Control Register:
Sub Address 0x08
bit 7
bit 6
SAT7
SAT6
1
0
bit 5
SAT5
0
bit 4
bit 3
SAT4
SAT3
Default Value
0
0
bit 2
SAT2
0
Default Value: 0x80
bit 1
bit 0
SAT1
SAT0
0
0
(4) Color Hue
Color Hue can be rotated in the AK8856. The rotation amount of Color Hue is determined by a value which is
set by the HUE Control Register (R/W) [Sub Address 0x09]. Rotation phase varies from ±45 degrees (0.35
degrees per step). The default value of the register is a non-adjusted value (0x00). The register value is in 2’s
complement format.
Bit allocation of Hue Control Register:
Sub Address 0x09
bit 7
bit 6
HUE7
HUE6
0
0
bit 5
HUE5
0
bit 4
bit 3
HUE4
HUE3
Default Value
0
0
bit 2
HUE2
0
Default Value: 0x00
bit 1
bit 0
HUE1
HUE0
0
0
MS0522-E-00
29
2006/Dec