Texas Instruments DM38x DaVinci, User Manual

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( )
( )
( )
( )
( )
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4095
7
1000 2047.5
10 1400
0.230
1
1024 128 837.3
27 1.33343
0.280
1
1024 128 1019.4
27 1.333302
4095
3
1000 878
10 1400
b
r
Y
D
D
LSB
A mV
mV
MHz
A
MHz
MHz
A
MHz
LSB
Sync mV
mV
= × × =
= × × × =
= × × × =
= × × =
0 0 1 0 0
1
0 0 0 1.505 0
255
0 0 1.902
0 0
302 59 154
1
186 280 94
64
286 55 341
b
r
Y
b D
r
D
Y A G
D A B
D R
A
G
B
R
 
     
 
     
= • •
 
     
 
     
−
     
 
 
   
   
= − −
   
   
−
   
0
M
1 0 0
0 1.505 0
0 0 1.902
Y G
b B
r R
E E
D E
D E
′ ′    
 
     
= • •
′ ′
     
   
  −
′ ′
     
0
M
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Internal Modules
119 SPRUHI7A – December 2012 – Revised June 2016
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Copyright © 2012–2016, Texas Instruments Incorporated
High-Definition Video Processing Subsystem (HDVPSS)
1.2.6.2.7.3 SECAM Encoding
1.2.6.2.7.3.1 DbDr Generation
First, SECAM YDbDr need to be generated using the CSC. In this example, the input is assumed to be
full-range RGB [0…255] and the output is assumed to have 7:3 picture sync ratio with zero setup.
The fundamental SECAM YDbDr equation is expressed as follows:
Where D'
b
has a range of 0 to ±1.33343 and D'
r
has a range of 0 to ±1.333302 and needs to be scaled so
that the resulted values have the corresponding deviation for the FM modulation.
The deviation calculation is explained in Section 1.2.6.2.7.3.3 .
Where D
b
has a range of 0 to ±1117 and D
r
has a range of 0 to ±1359.