Analog Devices ADV8003, Руководство по оборудованию

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ADV8003 Hardware Manual
Rev. B, August 2013 18
can be used to provide a second lower resolution output format. The PVSP and SVSP can be connected in parallel or in series.
The ADV8003 features a number of video enhancement controls such as detail enhancement, block noise reduction, mosquito noise
reduction and random noise reduction. Block and mosquito noise are related to the compression of video for transmission or encoding
onto a DVD or BD disc. Random noise is related to noise picked up during the transmission of video. The automatic contrast
enhancement feature offered by the ADV8003 intelligently stretches the brightness of an image to enhance the dark areas without
saturating the dark areas.
Note that the dual scaler variants of the ADV8003 are the following:
• ADV8003KBCZ-8/7
•
ADV8003KBCZ-8C/7C
The single scaler variants of the ADV8003 are the following:
• ADV8003KBCZ-8B/7B
• ADV8003KBCZ-7T
1.1.4. Bitmap On Screen Display
The AD8003 incorporates an OSD core capable of generating an internal bitmap based OSD. Customers can generate elaborate OSD
designs that can include bitmap images, 3D overlay and animation. Up to 256 regions in total can be created and displayed. These 256
regions are bitmap images defined during the design stage and can be characters, pictures, buttons and so on. Individual regions can be
alpha blended and prioritized versus other regions.
OSD Build OSD Scaler
OSD Blend
Video
External OSD
DDR2
OSD Build OSD Scaler
OSD Blend
Video 1
External OSD
DDR2
Video Video 2
Internal
OSD Generator
SPI
Figure 4: ADV8003 Bitmap OSD
The OSD is controlled by the host microcontroller via the ADV8003 SPI slave (serial port 1). In response to commands, the ADV8003
loads the data from the external SPI flash memory via the SPI master (serial port 2). The ADV8003 uses DDR2 memory when rendering
and blending the OSD. In order to lower the load of the DDR2 memory, there is a block in the ADV8003 OSD hardware called the OSD
co-processor. The OSD co-processor is responsible for handling upper level commands from the microcontroller and translating them
into lower level operations for the OSD and DMA which retrieves data from the external DDR2 memories.
The OSD blend can be switched between either of the two video streams routed through the OSD blend block without disturbing the
output video. This enables seamless OSD blending in dual zone systems.
Bitmap OSDs can be created and compiled using ADI’s software development tool,
Blimp OSD . This allows users to create their custom
OSDs and emulate them before integrating them into their system, abstracting the design task from the underlying OSD hardware. For
more details on the operation of the external OSD, design and system techniques, refer to the
Blimp OSD
documentation.