Structure containing data of a detected body/person such as its bounding_box, id and its 3D position. More...

Data Fields
int	id
	Body/person identification number. More...

unsigned char	unique_object_id [37]
	Unique id to help identify and track AI detections. More...

enum SL_OBJECT_TRACKING_STATE	tracking_state
	Body/person tracking state.

enum SL_OBJECT_ACTION_STATE	action_state
	Body/person action state.

struct SL_Vector3	position
	Body/person 3D centroid. More...

struct SL_Vector3	velocity
	Body/person 3D velocity. More...

float	position_covariance [6]
	Covariance matrix of the 3D position. More...

float	confidence
	Detection confidence value of the body/person. More...

int *	mask
	Mask defining which pixels which belong to the body/person (in bounding_box_2d and set to 255) and those of the background (set to 0). More...

struct SL_Vector2	bounding_box_2d [4]
	2D bounding box of the body/person represented as four 2D points starting at the top left corner and rotation clockwise. More...

struct SL_Vector3	head_position
	3D centroid of the head of the body/person. More...

struct SL_Vector3	dimensions
	3D body/person dimensions: width, height, length. More...

struct SL_Vector3	bounding_box [8]
	3D bounding box of the body/person represented as eight 3D points. More...

struct SL_Vector3	head_bounding_box [8]
	3D bounding box of the head of the body/person represented as eight 3D points. More...

struct SL_Vector2	head_bounding_box_2d [4]
	2D bounding box of the head of the body/person represented as four 2D points starting at the top left corner and rotation clockwise. More...

struct SL_Vector2	keypoint_2d [38]
	Set of useful points representing the human body in 2D. More...

struct SL_Vector3	keypoint [38]
	Set of useful points representing the human body in 3D. More...

float	keypoint_confidence [38]
	Array of detection confidences for each keypoint. More...

float	keypoint_covariances [38][6]
	Array of detection covariance for each keypoint. More...

struct SL_Vector3	local_position_per_joint [38]
	Array of local position (position of the child keypoint with respect to its parent expressed in its parent coordinate frame) for each keypoint. More...

struct SL_Quaternion	local_orientation_per_joint [38]
	Array of local orientation for each keypoint. More...

struct SL_Quaternion	global_root_orientation
	Global root orientation of the skeleton. More...

Detailed Description

Structure containing data of a detected body/person such as its bounding_box, id and its 3D position.

Field Documentation

◆ id

int SL_BodyData::id

Body/person identification number.

It is used as a reference when tracking the body through the frames.

Note: Only available if SL_BodyTrackingParameters.enable_tracking is activated.; Otherwise, it will be set to -1.

◆ unique_object_id

unsigned char SL_BodyData::unique_object_id[37]

Unique id to help identify and track AI detections.

It can be either generated externally, or by using sl_generate_unique_id() or left empty.

◆ position

struct SL_Vector3 SL_BodyData::position

Body/person 3D centroid.

Note: It is defined in SL_InitParameters.coordinate_unit and expressed in SL_RuntimeParameters.reference_frame.

◆ velocity

struct SL_Vector3 SL_BodyData::velocity

Body/person 3D velocity.

Note: It is defined in SL_InitParameters.coordinate_unit / s and expressed in SL_RuntimeParameters.reference_frame.

◆ position_covariance

float SL_BodyData::position_covariance[6]

Covariance matrix of the 3D position.

Note: It is represented by its upper triangular matrix value
= [p0, p1, p2]

[p1, p3, p4]

[p2, p4, p5]

where pi is position_covariance[i]

◆ confidence

float SL_BodyData::confidence

Detection confidence value of the body/person.

From 0 to 100, a low value means the body might not be localized perfectly.

◆ mask

int* SL_BodyData::mask

Mask defining which pixels which belong to the body/person (in bounding_box_2d and set to 255) and those of the background (set to 0).

Warning: The mask information is only available for tracked bodies (SL_OBJECT_TRACKING_STATE_OK) that have a valid depth.; Otherwise, the mask will not be initialized.

◆ bounding_box_2d

struct SL_Vector2 SL_BodyData::bounding_box_2d[4]

2D bounding box of the body/person represented as four 2D points starting at the top left corner and rotation clockwise.

Note: Expressed in pixels on the original image resolution, [0, 0] is the top left corner.
A ------ B

| Object |

D ------ C

◆ head_position

struct SL_Vector3 SL_BodyData::head_position

3D centroid of the head of the body/person.

Note: It is defined in SL_InitParameters.coordinate_unit and expressed in SL_RuntimeParameters.reference_frame.

◆ dimensions

struct SL_Vector3 SL_BodyData::dimensions

3D body/person dimensions: width, height, length.

Note: It is defined in SL_InitParameters.coordinate_unit and expressed in SL_RuntimeParameters.reference_frame.

◆ bounding_box

struct SL_Vector3 SL_BodyData::bounding_box[8]

3D bounding box of the body/person represented as eight 3D points.

Note: It is defined in SL_InitParameters.coordinate_unit and expressed in SL_RuntimeParameters.reference_frame.
1 ------ 2

/ /|

0 ------ 3 |

| Object | 6

| |/

4 ------ 7

◆ head_bounding_box

struct SL_Vector3 SL_BodyData::head_bounding_box[8]

3D bounding box of the head of the body/person represented as eight 3D points.

Note: It is defined in SL_InitParameters.coordinate_unit and expressed in SL_RuntimeParameters.reference_frame.

◆ head_bounding_box_2d

struct SL_Vector2 SL_BodyData::head_bounding_box_2d[4]

2D bounding box of the head of the body/person represented as four 2D points starting at the top left corner and rotation clockwise.

Note: Expressed in pixels on the original image resolution, [0, 0] is the top left corner.

◆ keypoint_2d

struct SL_Vector2 SL_BodyData::keypoint_2d[38]

Set of useful points representing the human body in 2D.

Note: Expressed in pixels on the original image resolution, [0, 0] is the top left corner.

Warning: In some cases, eg. body partially out of the image, some keypoints can not be detected. They will have negatives coordinates.

◆ keypoint

struct SL_Vector3 SL_BodyData::keypoint[38]

Set of useful points representing the human body in 3D.

Note: They are defined in SL_InitParameters.coordinate_unit and expressed in SL_RuntimeParameters.reference_frame.

Warning: In some cases, eg. body partially out of the image or missing depth data, some keypoints can not be detected. They will have non finite values.

◆ keypoint_confidence

float SL_BodyData::keypoint_confidence[38]

Array of detection confidences for each keypoint.

Note: They can not be lower than the SL_BodyTrackingRuntimeParameters.detection_confidence_threshold.

Warning: In some cases, eg. body partially out of the image or missing depth data, some keypoints can not be detected. They will have non finite values.

◆ keypoint_covariances

float SL_BodyData::keypoint_covariances[38][6]

Array of detection covariance for each keypoint.

Warning: In some cases, eg. body partially out of the image or missing depth data, some keypoints can not be detected. Their covariances will be 0.

◆ local_position_per_joint

struct SL_Vector3 SL_BodyData::local_position_per_joint[38]

Array of local position (position of the child keypoint with respect to its parent expressed in its parent coordinate frame) for each keypoint.

Note: They are expressed in SL_REFERENCE_FRAME_CAMERA or SL_REFERENCE_FRAME_WORLD.

Warning: Not available with SL_BODY_FORMAT_BODY_18.

◆ local_orientation_per_joint

struct SL_Quaternion SL_BodyData::local_orientation_per_joint[38]

Array of local orientation for each keypoint.

Note: The orientation is represented by a SL_Quaternion (SL_Quaternion q = SL_Quaternion(qx, qy, qz, qw);)

Warning: Not available with SL_BODY_FORMAT_BODY_18.

◆ global_root_orientation

struct SL_Quaternion SL_BodyData::global_root_orientation

Global root orientation of the skeleton.

The orientation is also represented by a quaternion with the same format as local_orientation_per_joint.

Note: The global root position is already accessible in keypoint attribute by using the root index of a given SL_BODY_FORMAT.

Warning: Not available with SL_BODY_FORMAT_BODY_18.

Data Fields