Samsung S5PC110 Manual page 1486

S5PC110_UM 7 6BTVOUT & VIDEO DAC
7.7 WAVEFORM GENERATION AND CHROMA MODULATION (CVBS MODULE)
The CVBS sub-module combines the timing information and video data to generate the waveforms of ITU-R BT
470 TV signals. Two different data paths do this procedure, namely, one is for luminance data (Y) and the other is
for chrominance data (C). For the luminance data path, horizontal/ vertical synchronization pulses are formed and
merged to a properly scaled and offset luminance video data (Y). For the chrominance data paths, base band
chrominance data (Cb and Cr) are modulated with a sub-carrier FSC along with the video standard, that is:
C(n) = U(n) * sin(2πFSC * n) + V(n) * cos(2πFSC * n),
where U(n) and V(n) denote properly scaled and offset versions of Cb(n) and Cr(n), respectively. Then a pilot
sinusoidal waveform, called a burst, is formed and added prior to the start of modulated chrominance data C at
each line. At the end of CVBS sub-module data paths, the luminance data (Y) and the chrominance data (C) is
merged into one channel and form composite data (CVBS).
Color
Space
Conversion
Y
HVSYNC/VBI DATA
CB
CR
Y
CVBS
DAC
C
QAM
Burst
Figure 7-12 Data Flow of CVBS Sub-Module
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