ml87v21071 Oki Semiconductor, ml87v21071 Datasheet - Page 29

• Manufacturer Part Number: ml87v21071
• Description: Video Signal Noise Reduction Ic With A Built-in Frame Memory
• Manufacturer: Oki Semiconductor

2. Video Signal Processing Functions
2.1 Motion-Adaptive 3D Noise Reduction
OKI Semiconductor
This IC performs noise reduction first by detecting noise and predicting motion using frame recursion, field
recursion, and line correlation, then by performing noise subtraction while performing motion compensation for
the detected noise. Moreover, it achieves adaptive noise reduction by synthesizing four NR data items based on
prediction of motion.
However, when INPR is set to 1, the field recursion stops and adaptive noise reduction is performed by the two
NR data items, frame recursion and line correlation.
Chrominance
• Principle of Noise Reduction
Luminance
input data
input data
Difference between the current field data and the filed data preceding one frame, one field, or one line is
extracted as time motion and noise independently for luminance and chrominance signals.
The low gain portion of this data is judged to be noise and the high gain portion to be motion and is extracted
as motion level detection noise.
The noise component extracted here is subjected to motion prediction by adjacent motion level and adjacent
code, then further subjected to compensation based on motion and is regarded as the final noise component.
Finally, noise reduction is carried out by subtracting this final noise data from the current field data.
Figure F2-1 (1) Noise Detection Type Noise Reduction Configuration
+
-
+
-
-
-
LPF
LPF
MSB
linear filter
linear filter
detection
detection
Motion
Motion
Non-
Non-
Chrominance noise detection
Luminance noise detection
Limiter
Limiter
Chrominance
compen-
motion level
Motion
compen-
sation
sation
compensation
Luminance
interlock
motion
+
+
-
-
-
-
memory
memory
Field
Field
PEDL87V21071-01
NR recursive data
NR recursive data
ML87V21071
Luminance
output data
Chrominance
output data
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