1996 Jun 20 2
Philips Semiconductors Preliminary specification
Decoder with High-Performance Scaler
(HPS) for Image Port (PELICAN)
SAA7112
FEATURES
The PELICAN SAA7112 is a video capture device for
application at the image port of a VGA controller, with
following feature highlights:
Video Decoder
• Six analog inputs, internal analog source selectors,
(e.g. 6 × CVBS or(2 × YC and 2 × CVBS) or
(1 × YC and 4 × CVBS)
• Two analog preprocessing channels, including built in
analog anti-alias filters
• Fully programmable static gain for the main channels or
Automatic Gain Control (AGC) for the selected
CVBS/Y channel
• Two 8 bit video CMOS Analog-to-Digital Converters
(ADCs)
• Automatic Clamp Control (ACC) for CVBS, Y and C
• Switchable white peak control
• On-chip line locked clock generation in accordance with
CCIR-601
• Digital PLL for synchronization and clock generation
from all standards and non-standard video sources,
e.g. consumer grade VTR
• Requires only one crystal (32.11 MHz) for all standards
• Horizontal and vertical sync detection
• Automatic detection of 50/60Hz field frequency, and
automatic switching between standards PAL and NTSC
• Luminance and chrominance signal processing for PAL
BGHI, PAL N, PAL M, NTSC M, NTSC N, NTSC 4.43
and SECAM
• User programmable luminance peaking or aperture
correction
• Cross-colour reduction for NTSC by chrominance
combination filtering
• PAL delay line for correcting PAL phase errors
• Real time status information output (RTCO)
• Independent Brightness Contrast Saturation (BCS)
adjustment for decoder part.
Video Scaler
• Horizontal and vertical down-scaling and up-scaling to
randomly sized windows
• Horizontal and vertical scaling range:
2 (zoom) to1⁄64(icon); vertical zoom might be restricted
• Anti-alias- and accumulating filter for horizontal scaling
• Vertical scaling with linear phase interpolation (6-bit
phase accuracy) and accumulating filter for anti-aliasing
• Horizontal phase correct up- and down-scaling for
improved signal quality of scaled data, especially for
compression and video phone applications, with 6-bit
phase accuracy
• Two independent programming sets for scaler part, to
define two ‘ranges’ per field or per frame
• Field-wise switching between decoder-part and
expansion port input
• Brightness, contrast and saturation controls for scaled
outputs.
VBI-data decoder and text slicer
• versatile VBI-data decoder, slicer, clock regeneration
and byte synchronization; e.g. for WST, NABST, Close
Caption, WSS, etc.
Audio clock generation
• Generation of a field locked audio master clock to
support a constant number of audio clocks per video
field
• Generation of an audio serial and left/right (channel)
clock signal.
Digital I/O interfaces
• Real time signal port (R-port), including continuous line
locked reference clock and real time status information
• Bidirectional expansion port (X-port) with half duplex
functionality (D1), 8-bit YUV
– output from decoder part, real time, or
– input to scaler part, e.g. video from MPEG-decoder
• Video image port (I-port) configurable for 8-bit (16-bit)
data in master mode (own clock), or slave mode
(external clock), with auxiliary timing and hand shake
signals
• 8-bit data Host port (H-port) for 16-bit extension of I-port
• Discontinuous data streams supported
• 32-word × 4 bytes FIFO register for video output data