Data Translation DT3162, User Manual

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Image Acquisition
14
Note:
If you select Interlaced, the field that you start on is
determined by the values for first active line (see page 22 ) and ROI
top (see page 23 ).
Acquisition Modes
Using software, you can specify one of three ways to acquire the
specified fields or frames:
• Single-pass synchronous mode
−
The DT3162 board acquires a
specified number of frames or fields, saves the corresponding
region on interest (ROI) in each frame/field to buffers in memory,
then stops. Refer to
page 22 for more information on ROIs.
In single-pass synchronous mode, all system resources are
devoted to the acquisition until the specified number of ROIs
have been saved; you cannot perform another operation until the
synchronous acquisition completes, including stopping the
operation.
For example, assume that you specified the acquire type as
interlaced, the acquisition mode as single-pass synchronous
mode, and the number of buffers as 3. When the acquisition
operation is started, the software allocates three buffers, acquires
the first frame and saves its ROI in buffer 1, acquires the second
frame and saves its ROI in buffer 2, acquires the third frame and
saves its ROI in buffer 3, then stops the operation. You can then
manipulate the data in the buffers as needed.
Specify SinglePassSync in software to use this mode.
• Single-pass asynchronous mode
−
Like single-pass synchronous
mode, the DT3162 board acquires a specified number of frames
or fields, saves the corresponding region on interest (ROI) in each
frame/field to buffers in memory, then stops.