Analog Devices ADV8005, Hardware Reference Manual

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UG-707 ADV8005 Hardware Reference Manual
matrix_prog_en , Encoder Map, Address 0xE402[3]
This bit is used to enable the manual mode for the ED/HD colour space converter.
Function
matrix_prog_en Description
0 (default) Automatic Mode
1 Manual Mode
Normally, there is no need to enable this feature because the CSC matrix automatically performs the CSC based on the input mode chosen (ED or
HD) and the output color space selected using
yuv_out . If the user needs to automatically update the CSC coefficients, the following procedure
is followed.
If the user selects the RGB output color space, the ED/HD CSC matrix scaler uses the following equations:
R = GY × Y + RV × Pr
G = GY × Y − ( GU × Pb) − ( GV × Pr)
B = GY × Y + BU × Pb
Note:
Subtractions in these equations are implemented in the hardware.
The following registers need to be programmed with these values:
•
gy [9:0] – Reg 0xE405 [7:0], Reg 0xE403 [1:0]
•
gu [9:0] – Reg 0xE406 [7:0], Reg 0xE404 [7:6]
•
gv [9:0] – Reg 0xE407 [7:0], Reg 0xE404 [5:4]
•
bu [9:0] – Reg 0xE408 [7:0], Reg 0xE404 [3:2]
•
rv [9:0] – Reg 0xE409 [7:0], Reg 0xE404 [1:0]
On powerup, the CSC matrix is programmed with the default values shown in
Table 75 .
Table 75: ED/HD Manual CSC Matrix Default Values
Register Default
0x03 0x03
0x04 0xF0
0x05 0x4E
0x06 0x0E
0x07 0x24
0x08 0x92
0x09 0x7C
When the ED/HD manual CSC matrix adjust feature is enabled, the default coefficient values in Reg 0xE403 to Reg 0xE409 are correct for the
HD color space only. The color components are converted according to the following 1080i and 720p standards (SMPTE 274M, SMPTE 296M):
R = Y + 1.575 Pr
G = Y − 0.468 Pr − 0.187 Pb
B = Y + 1.855 Pb
The conversion coefficients should be multiplied by 315 before being written to the ED/HD CSC matrix registers. This is reflected in the default
values for gy = 0x13B, gu = 0x03B, gv = 0x093, bu = 0x248, and rv = 0x1F0.
If the ED/HD manual CSC matrix adjust feature is enabled and another input standard (such as ED) is used, the scale values for gy, gu, gv, bu,
and rv must be adjusted according to this input standard color space. The user should consider that the color component conversion may use
different scale values.
Rev. A | Page 256 of 317