<< Click to Display Table of Contents >> Navigation: Halcon Interface > Acquisition Handle |
The main access principle, also within HALCON, is the manipulation of the NxLib parameter tree. Each access must be performed on a acquisition handle within Halcon.
An acquisition handle is created by calling open_framegrabber. Each acquisition handle simply acts as a reference to an NxLib tree item, i.e. the handle has an associated path, usually the tree's root or the root item of a camera.
Type |
Description |
'Stereo' |
Open: The device with serial number '<serial_number>' will be opened automatically during handle creation. open_framegrabber('Ensenso-NxLib', 0, 0, 0, 0, 0, 0, 'default', 0, 'Raw', -1, 'false', 'Stereo', '<serial_number>', 0, 0, AcqHandle) If '<serial_number>' is left empty, it will open the first detected stereo camera.
Parameters: •'grab_data_items' is set to 'Images/PointMap' by default.
Restrictions: •In 'set_framegrabber_param' the parameter 'do_execute' is not supported.
Close: The associated device will be closed upon destruction of the handle. |
'Monocular' |
Open: The device with serial number '<serial_number>' will be opened automatically during handle creation. open_framegrabber('Ensenso-NxLib', 0, 0, 0, 0, 0, 0, 'default', 0, 'Raw', -1, 'false', 'Monocular', '<serial_number>', 0, 0, AcqHandle) If '<serial_number>' is left empty, it will open the first detected mono camera.
Restrictions: •In 'set_framegrabber_param' the parameter 'do_execute' is not supported.
Close: The associated device will be closed upon destruction of the handle. |
'Item' |
open_framegrabber('Ensenso-NxLib', 0, 0, 0, 0, 0, 0, 'default', 0, 'Raw', -1, 'false', 'Item', '<node_path>', 0, 0, AcqHandle) If '<node_path>' is left empty, it will refer to the tree's root item.
Restrictions: •The operator 'grab_image' is not supported. •In 'set_framegrabber_param' the parameter 'do_execute' is only supported if the handle is referring to the tree's root item. |
Parameter |
Values |
Default |
Description |
auto_grab_data |
'true', 'false' |
'true' |
If set, it simplifies the usage of 'grab_data'. |
parallel_execution |
'true', 'false' |
'false' |
If set, the NxLib commands of this handle are executed in parallel to commands from other handles. See here for more information. |
error_code |
<error_code> |
Error code from the last raised NxLib API exception. |
|
error_item |
'<error_item_path>' |
Path of the item that raised the last NxLib API exception. |
|
error_text |
'<error_text>' |
Error text from the last raised NxLib API exception. |
|
generate_regions |
'true', 'false' |
'true' |
Enables/disables region generation in 'grab_data'. |
grab_data_items |
['<binary_node_path>'] |
List of binary nodes which will be provided when using 'grab_data'. |
|
replace_nans |
'true', 'false' |
'true' |
Enables/disables NaN replacement in 'grab_data'. |
color_space |
'Raw', 'Rectified' |
'Raw' |
Specifies which image will be returned in 'grab_image'. |