Acquiring An Image; Reading A File - National Instruments IMAQ Vision for Measurement Studio User Manual

Chapter 2 Getting Measurement-Ready Images

Acquiring an Image

You must use the
Note
acquisition device.

Reading a File

IMAQ Vision for LabWindows/CVI User Manual
Use one of the following methods to acquire images with a National
Instruments image acquisition (IMAQ) device:
• Acquire a single image using
this function, it initializes the IMAQ device and acquires the next
incoming video frame. Use this function for low-speed single capture
applications where ease of programming is essential.
• Acquire a single image using
function, it acquires the next incoming video frame on an IMAQ
device you have already initialized using
i
mgSessionOpen()
applications.
• Acquire images continually through a grab acquisition. Grab functions
perform high-speed acquisitions that loop continually on one buffer.
Use
imaqSetupGrab()
return a copy of the current image. Use
stop the acquisition.
• Acquire a fixed number of images using a sequence acquisition. Set up
the acquisition using
imaqStartAcquisition()
requested during setup. If you want to acquire only certain images,
supply
imaqSetupSequence()
frames to skip after each acquired frame.
• Acquire images continually through a ringed buffer acquisition. Set up
the acquisition using
imaqStartAcquisition()
acquired ring buffer. To get an image from the ring, call
imaqExtractFromRing()
imaqStopAcquisition()
imgClose()
Use
imaqReadFile()
computer into the image reference. You can read from image files stored in
several standard formats: BMP, TIFF, JPEG, PNG, and AIPD. The
software automatically converts the pixels it reads into the type of image
you pass in.
imaqEasyAcquire()
imaqSnap()
. Use this function for high-speed single capture
to start the acquisition. Use
imaqStopAcquisition()
imaqSetupSequence()
to acquire the number of images you
with a table describing the number of
imaqSetupRing()
to start acquiring images into the
or
imaqCopyRing()
to stop the acquisition.
to release resources associated with the image
to open and read data from a file stored on your
2-6
. When you call
. When you call this
imgInterfaceOpen()
imaqGrab()
. Use
. Use
. Use
and
to
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