IMAQ1394 Snap

NI-IMAQ for IEEE 1394 Cameras VI

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IMAQ1394 Snap

Configures, starts, acquires, and unconfigures a snap acquisition. Use a snap for low-speed or single-capture applications where ease of programming is essential. If you call this VI before calling IMAQ1394 Init, IMAQ1394 Snap uses cam0 by default. If the image type does not match the video format of the camera, this VI changes the image type to a suitable format.

Region of Interest specifies a rectangular portion of the image to be transferred into LabVIEW memory. This parameter is defined by an array of four elements: [Left, Top, Right, Bottom].
Note  If your camera supports Partial Image Size Format (Format 7), you can use that setting to change the size of the image transferred over the 1394 bus. These values are coerced to the next highest multiple of the unit width or height supported by your camera.
IMAQ1394 Session In is a unique reference to the camera, which you can obtain with IMAQ1394 Init.
Image In is the reference to the image that receives the captured pixel data.
error in (no error) is a cluster that describes the error status before this VI executes. If error in indicates that an error occurred before this VI was called, this VI may choose not to execute its function, but just pass the error through to its error out cluster. If no error has occurred, then this VI executes normally and sets its own error status in error out. Use the error handler VIs to look up the error code and to display the corresponding error message. Using the error in and error out clusters is a convenient way to check errors and to specify execution order by wiring the error output from one subVI to the error input of the next.
status is TRUE if an error occurred before this VI was called, or FALSE if not. If status is TRUE, code is a nonzero error code. If status is FALSE, code is zero or a warning code.

code is a number identifying an error or warning. If status is TRUE, code is a nonzero error code. If status is FALSE, code is zero or a warning code. Use the error handler VIs to look up the meaning of this code and display the corresponding error message.

source is a string that indicates the origin of the error, if any. Typically, source is the name of the VI in which the error occurred.

IMAQ1394 Session Out is a unique reference to the camera. IMAQ1394 Session Out is the same as IMAQ1394 Session In.
Image Out is the reference to the captured image.
error out is a cluster that describes the error status after this VI executes. If an error occurred before this VI was called, error out is the same as error in. Otherwise, error out shows the error, if any, that occurred in this VI. Use the error handler VIs to look up the error code and to display the corresponding error message. Using error in and error out clusters is a convenient way to check errors and to specify execution order by wiring the error output from one subVI to the error input of the next.
status is TRUE if an error occurred, or FALSE if not. If status is TRUE, code is a nonzero error code. If status is FALSE, code is zero or a warning code.

code is a number identifying an error or warning. If status is TRUE, code is a nonzero error code. If status is FALSE, code is zero or a warning code. Use the error handler VIs to look up the meaning of this code and display the corresponding error message.

source is a string that indicates the origin of the error, if any. Typically, source is the name of the VI in which the error occurred.

Note  Refer to Error Handling for error input and output information and error codes.
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