Data Translation DT3120, Руководство пользователя

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Principles of Operation
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Figure 4: Spatial Relationship of Video Signal
Types of Frames
The DT3120 board can acquire interlaced frames.
The video signal is defined as two consecutive fields, where the start
of each field is identified by the falling edge of the vertical sync.
These two fields are acquired to create the complete frame. The even
field contains lines 0, 2, 4, and so on; the odd field contains lines 1, 3,
5, and so on.
Using software, you can select one of the following types of frame
acquisitions:
• Interlaced frames, starting on the next even field (the default),
• Interlaced frames, starting on the next odd field,
First Active Pixel
First Active
Line
Active Video Area
Frame
Active
Line
Count
Total Lines
per Field
Active Pixel Count
Total Pixels per Line
Total Video Area
Frame
Height
Frame Width
Frame
Top
Frame Left