Intel 815 Manuel D’Utilisation
Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0
R
287
15.4.7. Overlay Color Correction Registers
Used for YUV sources only. Adjustments are made before the RGB conversion.
15.4.7.1.
OV0CLRC0—Overlay 0 Color Correction 0 Register
Memory Address Offset:
48h (R/W)
On-chip Reg. Mem Addr Offset:
30148h (RO; debug path)
Default Value:
00h
Access:
see address offset above
Size:
32 bits
31
17 16
8 7
0
Reserved Contrast
Brightness
Bit Description
31:17
Reserved.
16:8
Contrast. - 7.3F (3.6 format)
Bypassing Contrast, even for RGB, is accomplished by programming this field to 1.0
7:0
Brightness. Range ±127 a value of zero disables this adjustment affect. This value gets added to the
Y value after contrast multiply and just before RGB conversion.
Y value after contrast multiply and just before RGB conversion.
Bypassing Brightness, even for RGB, is accomplished by programming this field to 0.
15.4.7.2.
OV0CLRC1—Overlay 0 Color Correction 1 Register
Memory Address Offset:
4Ch (R/W)
On-chip Reg. Mem Addr Offset:
3014Ch (RO; debug path)
Default Value:
00h
Access:
see address offset above
Size:
32 bits
31
10
9
0
Reserved Saturation/CrCb
Bit Description
31:10
Reserved.
9:0
Saturation/CrCb. This operates in two modes. When YUV data is being operated on, the register
contains the saturation value. When CbCr data is being used, it is the sum of the saturation multiplier
value added to the CbCr scale factor (128/112).
contains the saturation value. When CbCr data is being used, it is the sum of the saturation multiplier
value added to the CbCr scale factor (128/112).
This unsigned fixed point number is in 3.7 format.
Bypassing Saturation, even for RGB, is accomplished by programming this field to 1.0