Philips Semiconductors
Digital Signal Processor (DSP) for
cameras
Preliminary specification
SAA8110G
handbook, full pagewidth
UV 8
(−127 to 128)
NOISE
REDUCTION
FALSE COLOUR
CORRECTION
UV GAIN
8
CONTROL
UV
(−127 to 128)
false colour
white clip
(from Y-processing) (from RGB-separation)
MGK157
Fig.7 UV-processing.
UV-processing
The chrominance component includes several features:
• Noise reduction for high frequencies
• False colour correction: a colour killer cuts the false
colour components in the UV signals
• UV-gain control used to set the correct UV levels for
PAL/NTSC encoding.
As the colour filter saturation levels may be different in the
CCD, the white clip is used in the UV-processing to
suppress colour errors in case of high exposure.
Digital output formatter
This block contains several features:
• Generation of a synchronous clock LLC (twice the clock
frequency)
• Generation of three synchronization signals (HREF,
CREF and VS)
• Synchronization of the output data to the output clock
LLC
• Generation of a CIF/QCIF output format for several type
of sensors (see Table 1)
• Selection of the required digital output format (8-bit
multiplexed YUV standard D1/CCIR 656, including the
generator of SAV/EAV codes or 16-bit multiplexed YUV
4 : 2 : 2 standard DTV2/CCIR601).
Note that the D1 frequency data rate is twice the DTV2
frequency data rate.
Moreover, using a high resolution PAL and NTSC CCDs,
it is possible to generate the following formats by means of
cutting or down-sampling.
• CIF 352 × 288 at 25 frame/second and CIF 352 × 240 at
30 frame/second
• QCIF 176 × 144 at 25 frame/second and QCIF
176 × 120 at 30 frame/second.
Table 1 CIF/QCIF output format for different sensor
types
INPUT FORMAT
PAL/NTSC-sensor
CIF
OUTPUT FORMAT
CIF ‘full screen’
CIF ‘zoom-by-2’
QCIF ‘full screen’
QCIF ‘zoom-by-2’
QCIF ‘zoom-by-4’
QCIF ‘full screen’
QCIF ‘zoom-by-2’
1997 Jun 13
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