National Instruments IEEE 1394 用户手册

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页码 61
Chapter 2
Basic Acquisition with NI-IMAQ for IEEE 1394 Cameras
2-14
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Sequence
The low-level sequence examples demonstrate how to perform a sequence 
acquisition using low-level calls. The program sets up a one-shot, 
multi-image acquisition and starts the acquisition. The main loop iterates 
once for each internal buffer. In the main processing loop, the program 
acquires an image and processes it. After the loop, the program stops the 
acquisition, unconfigures the acquisition, and closes the session.
Figure 2-7 illustrates the programming order of a low-level sequence 
acquisition.
Figure 2-7.  Low-Level Sequence Flowchart
Opens and Configures Camera
Starts Transferring Data from Camera
to Host Computer
Executes User-Specific Image
Processing
Stops Transferring Data from Camera
to Host Computer
Configures a Single-Shot Multiple-
Buffer Acquisition
Closes the Camera Session
Frees IEEE 1394 Bandwidth and Memory
Resources Used by the Acquisition
Copies and Decodes Buffer Number
i
, Where 
i
 is Between 0 and (
n
 – 1)
(Loop)
Loop 
n
 Times
Initialize
Configure
Start
Acquire
User-Specific Functions
Stop
Clear
Close