SAA8116 Datasheet, PDF (13/60 Pages) NXP Semiconductors – Digital PC-camera signal processor including microcontroller and USB interface

Philips Semiconductors
Digital PC-camera signal processor including
microcontroller and USB interface
Product specification
SAA8116
Video signal processor
OPTICAL BLACK PROCESSING
The first processing block of the SAA8116 is a digital
clamp (denoted as PRE-PROCESSING in Fig.1). It is used
to align the optical black level to zero or to any arbitrary
value.
The average value of the black is measured in the
programmable optical black window and sent to the
microcontroller for adjustment, if necessary. The value
fixed by the microcontroller is subtracted from the
incoming data stream.
The optical black window has a fixed size of 16 pixels
(horizontally) by 128 (vertically); the position of this
window is fully programmable.
Each of the four colour filter inputs has its own offset and
gain.
DEFECT PIXEL CONCEALMENT
Up to 128 Defect Pixel Coordinates (DPC) can be taken
into account for concealment. The method is based either
on a horizontal linear interpolation, or on a copy of a
neighbouring pixel of the same colour.
RGB COLOUR RECONSTRUCTOR
In the RGB colour reconstructor (denoted as RGB
RECONSTRUCTION in Fig.1), an RGB triplet is
interpolated for every pixel on a 3 × 3 neighbourhood
matrix.
With B and W sensors, the RGB colour reconstructor can
be disabled, thus maintaining the full sensor resolution.
Vertical contours and video level information (white clip)
are extracted at this stage (see Fig.5).
handbook, full pagewidth
CCD inputs
LINE
MEMORY
LINE
MEMORY
10
RGB
COLOUR
SEPARATION
FCE340
R
G
B
White clip
Edges
Fig.5 RGB reconstructor diagram.
2001 May 04
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