query_calib_data_observ_indices — Query information about the relations between cameras, calibration objects,
and calibration object poses.
query_calib_data_observ_indices( : : CalibDataID, ItemType, ItemIdx : Index1, Index2)
A calibration data model (CalibDataID) contains a collection of
observations, which are added to the model by
set_calib_data_observ_points. Each observation is associated
to an observing camera, an observed calibration object, and a calibration
object pose. With the operator query_calib_data_observ_indices, you
can query observation indices associated to a camera or an calibration
object, depending on the parameter ItemType.
For ItemType='camera', you must pass a
valid camera index in ItemIdx. Then, Index1 returns
a list of calibration object indices and Index2 returns a
list of pose indices. Each pair [Index1[I],Index2[I]]
represents calibration object pose that are 'observed' by camera
ItemIdx.
For ItemType='calib_obj', you must specify
a valid calibration object index in ItemIdx. Then,
Index1 returns a list of camera indices and Index2 returns
a list of corresponding calibration object pose indices. Each pair
[Index1[I],Index2[I]] denotes that camera Index1[I]
is observing the Index2[I]th pose of calibration object
ItemIdx.
This operator is particularly suitable for accessing observation data of a calibration data model whose configuration is unknown at the moment of its usage (e.g., if it was just read from a file). As a special case, this operator can be used to get the precise list of poses of one calibration object (see the example).
This operator modifies the state of the following input parameter:
The value of this parameter may not be shared across multiple threads without external synchronization.
CalibDataID (input_control, state is modified) calib_data → (handle)
Handle of a calibration data model.
ItemType (input_control) string → (string)
Kind of referred object.
Default value: 'camera'
List of values: 'calib_obj', 'camera'
ItemIdx (input_control) number → (integer)
Camera index or calibration object index
(depending on the selected ItemType).
Default value: 0
Suggested values: 0, 1, 2
Index1 (output_control) number-array → (integer)
List of calibration object indices or list of
camera indices (depending on ItemType).
Index2 (output_control) number-array → (integer)
Calibration object numbers.
* Read a calibration model from a file.
read_calib_data ('calib_data.ccd',CalibDataID)
* Get calibration object indices assigned to calibration object 0.
query_calib_data_observ_indices (CalibDataID, 'calib_obj', 0, _, \
CalibObjPoseIndices)
* CalibObjPoseIndices contains the list of pose indices of calibration
* object 0. In order to be stored in the model, each calibration object
* needs to be observed by at least one camera in the setup (a calibration
* object pose that is not observed by any camera cannot be stored in
* the model). Typically, a calibration object pose can be observed by more
* than one camera. Hence, some calibration object pose indices might appear
* repeatedly in CalibObjPoseIndices. We use tuple_sort and tuple_uniq to
* extract a unique list of calibration object pose indices for calibration
* object 0.
tuple_sort (CalibObjPoseIndices, CalibObjPoseIndices)
tuple_uniq (CalibObjPoseIndices, CalibObjPoseIndices)
* Get poses of calibration objects observed by camera 2.
calibrate_cameras (CalibDataID, Error)
query_calib_data_observ_indices (CalibDataID, 'camera', 2, CalibObjIndices,\
CalibObjPoseIndices)
for I := 0 to |CalibObjIndices|-1 by 1
get_calib_data (CalibDataID, 'calib_obj_pose', \
[CalibObjIndices[I], CalibObjPoseIndices[I]], \
'pose', CalibObjPose)
endfor
Calibration