grab_data — Synchronous grab of images and preprocessed image data from the specified image acquisition device.
The operator grab_data grabs images and preprocessed image data via the image acquisition device specified by AcqHandle. 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_framegrabber and set_framegrabber_param. Depending on the current configuration of the image acquisition device, the preprocessed image data can be returned in terms of images (Image), regions (Region), XLD contours (Contours), and control data (Data).
To abort the grab, the operator set_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.
Basically an image acquisition handle AcqHandle cannot be used in multiple threads. However, possible exceptions are described in the specific reference documentation of the respective image acquisition interface. Different image acquisition handles can be used safely with different threads for each handle.
For a multithreaded application all image acquisition operators (as listed in open_framegrabber) are an own group in which info_framegrabber, open_framegrabber, close_framegrabber and close_all_framegrabbers are executed exclusively.
grab_data runs in parallel with all non-exclusive operators inside and outside of this group.
Grabbed image data.
Preprocessed image regions.
Preprocessed XLD contours.
Handle of the acquisition device to be used.
Preprocessed control data.
* 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 and segment image grab_data (Image, Region, Contours, AcqHandle, Data) * Process Region... close_framegrabber(AcqHandle)
If the image acquisition device is open and supports the image acquisition via grab_data, the operator grab_data returns the value 2 (H_MSG_TRUE). Otherwise an exception is raised.
open_framegrabber, grab_image_start, set_framegrabber_param
grab_data_async, grab_image_start, grab_image, grab_image_async, set_framegrabber_param, close_framegrabber
open_framegrabber, info_framegrabber, set_framegrabber_param