Operator Reference

HALCON Operator Reference / Image / Acquisition
ClassesClasses | | Operators

grab_imageT_grab_imageGrabImageGrabImagegrab_image (Operator)

grab_imageT_grab_imageGrabImageGrabImagegrab_image — Synchronous grab of an image from the specified image acquisition device.

Signature

grab_image( : Image : AcqHandle : )

Herror T_grab_image(Hobject* Image, const Htuple AcqHandle)

void GrabImage(HObject* Image, const HTuple& AcqHandle)

void HImage::GrabImage(const HFramegrabber& AcqHandle)

HImage HFramegrabber::GrabImage() const

static void HOperatorSet.GrabImage(out HObject image, HTuple acqHandle)

void HImage.GrabImage(HFramegrabber acqHandle)

HImage HFramegrabber.GrabImage()

def grab_image(acq_handle: HHandle) -> HObject

Description

The operator grab_imagegrab_imageGrabImageGrabImagegrab_image grabs an image via the image acquisition device specified by AcqHandleAcqHandleAcqHandleacqHandleacq_handle. The desired operational mode of the image acquisition device as well as a suitable image part and additional interface-specific settings can be specified using the operators open_framegrabberopen_framegrabberOpenFramegrabberOpenFramegrabberopen_framegrabber and set_framegrabber_paramset_framegrabber_paramSetFramegrabberParamSetFramegrabberParamset_framegrabber_param.

To abort the grab, the operator set_framegrabber_paramset_framegrabber_paramSetFramegrabberParamSetFramegrabberParamset_framegrabber_param with the parameter 'do_abort_grab' can be used if the specific image acquisition interface supports it. Note that as an exception from the description of the concurrent usage in multiple threads (see below) 'do_abort_grab' can also be used from another thread.

Attention

For a multithreaded application, info_framegrabberinfo_framegrabberInfoFramegrabberInfoFramegrabberinfo_framegrabber, open_framegrabberopen_framegrabberOpenFramegrabberOpenFramegrabberopen_framegrabber, and close_framegrabberclose_framegrabberCloseFramegrabberCloseFramegrabberclose_framegrabber are executed exclusively.

grab_imagegrab_imageGrabImageGrabImagegrab_image runs in parallel with all non-exclusive operators inside and outside of this group.

Execution Information

  • Multithreading type: reentrant (runs in parallel with non-exclusive operators).
  • Multithreading scope: global (may be called from any thread).
  • Processed without parallelization.

Parameters

ImageImageImageimageimage (output_object)  image → objectHImageHObjectHObjectHobject * (byte / uint2)

Grabbed image.

AcqHandleAcqHandleAcqHandleacqHandleacq_handle (input_control)  framegrabber → HFramegrabber, HTupleHHandleHTupleHtuple (handle) (IntPtr) (HHandle) (handle)

Handle of the acquisition device to be used.

Example (HDevelop)

* Select a suitable image acquisition interface name AcqName
info_framegrabber(AcqName,'port',Information,Values)
* Open image acquisition device using the default settings, see
* documentation of the actually used interface for more details
open_framegrabber(AcqName,1,1,0,0,0,0,'default',-1,'default',-1.0, \
                  'default','default','default',-1,-1,AcqHandle)
grab_image(Image,AcqHandle)
close_framegrabber(AcqHandle)

Result

If the image could be acquired successfully, the operator grab_imagegrab_imageGrabImageGrabImagegrab_image returns the value 2 ( H_MSG_TRUE) . Otherwise an exception is raised.

Possible Predecessors

open_framegrabberopen_framegrabberOpenFramegrabberOpenFramegrabberopen_framegrabber, set_framegrabber_paramset_framegrabber_paramSetFramegrabberParamSetFramegrabberParamset_framegrabber_param

Possible Successors

grab_image_startgrab_image_startGrabImageStartGrabImageStartgrab_image_start, grab_image_asyncgrab_image_asyncGrabImageAsyncGrabImageAsyncgrab_image_async, close_framegrabberclose_framegrabberCloseFramegrabberCloseFramegrabberclose_framegrabber

See also

open_framegrabberopen_framegrabberOpenFramegrabberOpenFramegrabberopen_framegrabber, info_framegrabberinfo_framegrabberInfoFramegrabberInfoFramegrabberinfo_framegrabber, set_framegrabber_paramset_framegrabber_paramSetFramegrabberParamSetFramegrabberParamset_framegrabber_param

Module

Foundation

ClassesClasses | | Operators