Data Translation DT3162, Руководство пользователя

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Principles of Operation
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Video Area
The video image area is composed of pixels and lines of video. The
total video area is the complete set of horizontal and vertical input
lines from which you extract the active video area and the region of
interest (ROI) within the active video area that you want to acquire.
The total video area includes all parts of the signal, including
nonvisual portions such as horizontal and vertical blanking
information. (Blanking information is the data not included in the
active video area; it contains sync and other information.)
Using software, you can set the line, or horizontal, frequency. For
internal (composite syncs), this value determines how often the lines
occur. If sync output mode is enabled, this value also determines how
often the lines are output. Values range from 1 to 65535 Hz, in
increments of 1.
The total video area is as wide as the total pixels per line (the entire
area between two consecutive horizontal sync signals) and as tall as
the total lines per frame.
You can use software to define the total video area for the DT3162
board.
Table 1 lists the settings you can program.
Table 1: Total Video Area Settings
Setting Description Range
a
a. In increments of 1.
Total Pixels per Line The total number of pixels in a
single horizontal line of video,
where a horizontal line is
defined as the area between
two consecutive horizontal
sync signals. 1 to 4095 pixels
Total Lines per Frame The total number of lines in a
single frame of video. 1 to 4095 lines