Matrox Morphis QxT, Установка и справочник по оборудованию

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34 Chapter 4: Hardware reference
Video decoders
The acquisition section has 16 standard video decoders. In addition to digitizing
video, these decoders feature internal filtering and automatic gain control.
Gain
The automatic gain control (AGC) allows the video signal input range to be
optimized before being digitized. You can, however, disable the AGC and set the
gain manually, using the
MdigControl() function, with
M_GRAB_AUTOMATIC_INPUT_GAIN
set to
M_DISABLE
and
M_GRAB_INPUT_GAIN
set to any integer value from 0 to 255.
Digitizing
component
The multi-standard video decoders can convert analog composite (CVBS) video
in NTSC/PAL format, to digitized video in YUV16 (4:2:2).
Each decoder supports the following video timing settings :
Video capture controller
Once the analog video has been converted to digitized video, it enters a component
called the
video capture controller .
The video capture controller accepts all data signals provided by the decoders and
transfers them to acquisition memory. It is also capable of performing vertical and
horizontal flipping of the image during capture.
Square pixel video formats
NTSC PAL
Pixel sampling rate (MHz) 12.27 14.75
Y component sampling rate ( MHz) 12.27 14.75
U and V components ( MHz) 6.14 each 7.38 each
Digitizing component sampling rate (MHz) 24.54 29.5
Field rate (Hz) 60 50
Pixel/line (pixels) 780 944
Active pixel/line (pixels) 640 768
Active lines/frame (lines) 480 576
Line rate (KHz) 15.734 15.625