Color Space Conversion Matrix; Ed/Hd Manual Csc Matrix Adjust Feature - Analog Devices ADV8003 Hardware Manual

8.4.9.

Color Space Conversion Matrix

The input to the encoder block on the ADV8003 should always be in a YCbCr color space. If an RGB color space is present at the input
pins, the CSC on the I/O block of the ADV8003 can be used to convert it to YCbCr. It is possible, however, to convert from YCbCr to an
RGB stream in the encoder. The encoder output color space can be programmed using yuv_out.
yuv_out, Encoder Map, Address 0xE402[5]
This bit is used to select the output color space for the encoder.
Function
yuv_out
0
1 

8.4.10. ED/HD Manual CSC Matrix Adjust Feature

The ED/HD manual CSC matrix adjust feature provides custom coefficient manipulation for the YPbPr to RGB CSC and is used in ED and
HD modes only. matrix_prog_en
matrix_prog_en, Encoder Map, Address 0xE402[3]
This bit is used to enable the manual mode for the ED/HD color space converter.
Function
matrix_prog_en
0 
1
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]
Rev. B, August 2013
Sample Color Y Value
Magenta 106
Description
RGB component outputs
YPrPb component outputs
can be used to enable this feature.
Description
Automatic mode
Manual mode
Cr Value
(0x6A) 222 (0xDE)
321
ADV8003 Hardware Manual
Cb Value
202 (0xCA)