STV3550B STMicroelectronics, STV3550B Datasheet - Page 29

• Manufacturer Part Number: STV3550B
• Manufacturer: STMicroelectronics

Specifications of STV3550B

• Operating Temperature (min): 0C
• Operating Temperature (max): 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / Rohs Status: Compliant

STV3550
3.3.4
3.3.5
3.3.6
Figure 14. Image improvement block diagram
Brightness estimator
The Brightness Estimator provides the value of the average field brightness of the picture. It
can be used to hardware tune the two brightness correction functions (spectral processing
and contrast enhancer).
Otherwise, a manual mode enables the CPU to force the average brightness value of the
image.
Histogram
A high-resolution, non-linear histogram that uses 16 levels to characterize the image
luminance is included.
The accumulation of the histogram is done through an entire field and is ready to be used at
the next V sync signal. A window for histogram calculation can be selected for reducing the
image size which will be used for histogram processing.
Contrast enhancer
The luminance processing block works only on the low pass spectrum of the input signal.
All these algorithms are based on the same model
segments for contrast modification: the high limit (Yhl), the low limit (Yll) and the middle
segment (Ym).
Yin
Cbin, Crin
Input Stage
Autoformat
Brightness
Detection
Histogram
Estimator
Filtering
Chrominance Processing
Color Transient
Improvement
Brightness
High pass
Low pass
Average
Spectral Processing
Contrast Enhancer
Adaptive Peaking
White Stretch
Black Stretch
Grey Stretch
B&W Shrink
& Coring
(Figure
Cbout, Crout
15) that uses three different
Video function description
Mix
Yout
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