Data Sheet
ADV7180
VIDEO PROCESSOR
STANDARD DEFINITION PROCESSOR
MACROVISION
DETECTION
STANDARD
AUTODETECTION
SLLC
CONTROL
VBI DATA
RECOVERY
DIGITIZED CVBS
DIGITIZED Y (YC)
LUMA
DIGITAL
FINE
LUMA
GAIN
CONTROL
LUMA
FILTER
LUMA
RESAMPLE
LUMA
2D COMB
CLAMP
LINE
AV
SYNC
EXTRACT
RESAMPLE
CONTROL
VIDEO DATA
OUTPUT
LENGTH
CODE
PREDICTOR
INSERTION
DIGITIZED CVBS
DIGITIZED C (YC)
CHROMA
DIGITAL
FINE
CHROMA
GAIN
CONTROL
MEASUREMENT
BLOCK (≥ I C)
CHROMA
DEMOD
CHROMA
FILTER
CHROMA
RESAMPLE
CHROMA
2D COMB
2
CLAMP
VIDEO DATA
PROCESSING
BLOCK
f
SC
RECOVERY
Figure 18. Block Diagram of the Video Processor
Figure 18 shows a block diagram of the ADV7180 video processor.
The ADV7180 can handle standard definition video in CVBS,
Y/C, and YPrPb formats. It can be divided into a luminance and
chrominance path. If the input video is of a composite type
(CVBS), both processing paths are fed with the CVBS input.
SD CHROMA PATH
The input signal is processed by the following blocks:
•
Chroma digital fine clamp. This block uses a high precision
algorithm to clamp the video signal.
•
Chroma demodulation. This block employs a color
subcarrier (fSC) recovery unit to regenerate the color
subcarrier for any modulated chroma scheme. The
demodulation block then performs an AM demodulation
for PAL and NTSC, and an FM demodulation for SECAM.
Chroma filter. This block contains a chroma decimation
filter (CAA) with a fixed response and some shaping filters
(CSH) that have selectable responses.
Chroma gain control. AGC can operate on several different
modes, including gain based on the color subcarrier
amplitude, gain based on the depth of the horizontal sync
pulse on the luma channel, or fixed manual gain.
Chroma resample. The chroma data is digitally resampled
to keep it perfectly aligned with the luma data. The
resampling is done to correct for static and dynamic line
length errors of the incoming video signal.
SD LUMA PATH
The input signal is processed by the following blocks:
•
Luma digital fine clamp. This block uses a high precision
algorithm to clamp the video signal.
•
•
•
Luma filter. This block contains a luma decimation filter
(YAA) with a fixed response and some shaping filters
(YSH) that have selectable responses.
•
•
Luma gain control. The automatic gain control (AGC) can
operate on a variety of different modes, including gain based
on the depth of the horizontal sync pulse, peak white mode,
and fixed manual gain.
Luma resample. To correct for line length errors as well as
dynamic line length changes, the data is digitally resampled.
Luma 2D comb. The 2D comb filter provides Y/C separation.
AV code insertion. At this point, the decoded luma (Y) signal
is merged with the retrieved chroma values. AV codes can
be inserted (as per ITU-R BT.656).
•
•
•
•
•
Chroma 2D comb. The 2D, five line, superadaptive comb
filter provides high quality Y/C separation in case the input
signal is CVBS.
AV code insertion. At this point, the demodulated chroma
(Cr and Cb) signal is merged with the retrieved luma values.
AV codes can be inserted (as per ITU-R BT.656).
Rev. G | Page 25 of 120
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