National Instruments IEEE 1394 用户手册

© National Instruments Corporation

This chapter contains an overview of the NI-IMAQ for IEEE 1394 
Cameras library, a description of the acquisition flow of NI-IMAQ for 
IEEE 1394 Cameras, and generic programming examples. The chapter also 
contains flowcharts of high-level and low-level snap, grab, and sequence 
operations.

The NI-IMAQ for IEEE 1394 Cameras application programming interface 
(API) is divided two main function groups: high-level and low-level.

•

High-level functions—Use to capture images quickly and easily. If 
you need more advanced functionality, you can mix high-level 
functions with low-level functions.

–

Snap functions—Capture all or a portion of a single image to the 
user buffer.

–

Grab functions—Perform an acquisition that loops continually on 
one or more internal buffers. You can copy the last acquired buffer 
to a separate user buffer for processing or analysis.

–

Sequence functions—Acquire a specified number of internal 
buffers and then stops.

–

Trigger functions—Control the trigger mode of the IEEE 1394 
camera.

•

Low-level functions—Use when you require more direct control of the 
image acquisition.

–

Acquisition functions—Configure, start, stop, and unconfigure an 
image acquisition, or examine a user buffer during an acquisition.

–

Attribute functions—Examine and change the acquisition or 
camera attributes.

–

Utility functions—Display an image in a window, save an image 
to a file, or to get detailed error information.