Phytec eGrabber-4plus, Руководство по оборудованию

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Driver Software
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PHYTEC Meßtechnik GmbH 2004 L-608e_4
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Also black/white videosources can be connected to the
eGrabber-4plus . The processing of gray scale pictures with 256 gray
graduations is already provided in the Grabber and can be activated by
software. Applying black/white sources, the sharpness of the image
can be improved by deactivating the luma notch filter by software.
After the A/D-converters follow operational components, which
decompose the data stream of the image into its components: After the
chroma-demodulator the data are separated according to brightness.
(Y) and color portion (Cr/Cb). Subsequently follows the digital
correction of brightness, contrast, color saturation and the size and
resolution of the image.
The following video format converter produces the data formats,
which are provided by the eGrabber-4plus. Via a datamultiplexer the
required format is selected and stored in the 630 Byte FIFO memory.
The FIFO is an interface to the following PCI-bus interface, which is
responsible for the data transfer through the PCI-bus.
The image data are transferred by DMA to the main memory of the
PC. For each field a separate DMA-channel is used. The transfer can
be organized in different ways. For this reason a pixel instruction list
for each field is used, which is denoted RISC-Program, for the
PCI-controller of the eGrabber-4plus. The principle of the pixel
instruction list is more closely addressed in section 5.1.2.
Via the PCI-controller the access to the local registers is managed.
This allows the adjustment of the parameters of the Grabber and the
acknowledgement of the actual status. This registers are also used to
actuate the I/O- lines defined by the user, and to drive the I²C interface
integrated in the Grabber.