Data Translation MACH Series, User Manual

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Principles of Operation
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Video Input Signal
This section describes the following aspects of the video input signal:
• Video signal types,
• Video input channels,
• Chrominance notch filter,
• Black and white levels,
• Pixel clock,
• External trigger, and
• Input look-up table.
Video Signal Types
The DT3152-LS frame grabber board can acquire monochrome
images from the following types of standard, composite video input
signals:
• RS-170
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Standard for 60 Hz monochrome video signals. A video
frame consists of 525 lines, 480 lines of which are visible.
• CCIR
−
Standard for 50 Hz monochrome video signals. A video
frame consists of 625 lines, 576 lines of which are visible.
• NTSC
−
Standard for 60 Hz color video signals; color is
superimposed over the monochrome RS-170 image. A video
frame consists of 525 lines, 480 lines of which are visible.
• PAL
−
Standard for 50 Hz color video signals; color is
superimposed over the monochrome RS-170 image. A video
frame consists of 625 lines, 576 lines of which are visible.
In addition, the DT3152-LS can acquire monochrome images from
nonstandard variable-scan video sources, such as line-scan,
slow-scan, SEM, and high-resolution cameras. These nonstandard
video sources provide their own control signals.