User Generator

Modules
	Skeleton Capability
	Pose Detection Capability
	Hand Touching FOV Edge Capability
Functions
XN_C_API XnStatus XN_C_DECL	xnCreateUserGenerator (XnContext *pContext, XnNodeHandle *phUserGenerator, XnNodeQuery *pQuery, XnEnumerationErrors *pErrors)
XN_C_API XnUInt16 XN_C_DECL	xnGetNumberOfUsers (XnNodeHandle hInstance)
XN_C_API XnStatus XN_C_DECL	xnGetUsers (XnNodeHandle hInstance, XnUserID *pUsers, XnUInt16 *pnUsers)
XN_C_API XnStatus XN_C_DECL	xnGetUserCoM (XnNodeHandle hInstance, XnUserID user, XnPoint3D *pCoM)
XN_C_API XnStatus XN_C_DECL	xnGetUserPixels (XnNodeHandle hInstance, XnUserID user, XnSceneMetaData *pScene)
XN_C_API XnStatus XN_C_DECL	xnRegisterUserCallbacks (XnNodeHandle hInstance, XnUserHandler NewUserCB, XnUserHandler LostUserCB, void *pCookie, XnCallbackHandle *phCallback)
XN_C_API void XN_C_DECL	xnUnregisterUserCallbacks (XnNodeHandle hInstance, XnCallbackHandle hCallback)
XN_C_API XnStatus XN_C_DECL	xnRegisterToUserExit (XnNodeHandle hInstance, XnUserHandler handler, void *pCookie, XnCallbackHandle *phCallback)
XN_C_API void XN_C_DECL	xnUnregisterFromUserExit (XnNodeHandle hInstance, XnCallbackHandle hCallback)
XN_C_API XnStatus XN_C_DECL	xnRegisterToUserReEnter (XnNodeHandle hInstance, XnUserHandler handler, void *pCookie, XnCallbackHandle *phCallback)
XN_C_API void XN_C_DECL	xnUnregisterFromUserReEnter (XnNodeHandle hInstance, XnCallbackHandle hCallback)

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Detailed Description

A User Generator node is a Generator that identifies a user in the scene. It supports all Generator functions, and adds additional functions.

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Function Documentation

XN_C_API XnStatus XN_C_DECL xnCreateUserGenerator	(	XnContext *	pContext,
		XnNodeHandle *	phUserGenerator,
		XnNodeQuery *	pQuery,
		XnEnumerationErrors *	pErrors
	)

Creates a user generator.

Parameters:

pContext	[in] The context in which to create the user generator.
phUserGenerator	[out] A handle to the created user generator.
pQuery	[in] Optional. Can be used to select which user generator to create. If not specified, this function may create any user generator that is available.
pErrors	[in] Optional. If provided, will be filled with information about user generators that could not be created.

XN_C_API XnUInt16 XN_C_DECL xnGetNumberOfUsers

(

XnNodeHandle

hInstance

)

Get current number of users.

Parameters:

hInstance

[in] A handle to the instance

XN_C_API XnStatus XN_C_DECL xnGetUserCoM	(	XnNodeHandle	hInstance,
		XnUserID	user,
		XnPoint3D *	pCoM
	)

Get the center of mass of a user.

Parameters:

hInstance	[in] A handle to the instance
user	[in] The user for which to get the center of mass
pCoM	[out] The center of mass

XN_C_API XnStatus XN_C_DECL xnGetUserPixels	(	XnNodeHandle	hInstance,
		XnUserID	user,
		XnSceneMetaData *	pScene
	)

Get the pixels that belong to a user.

The output is in a XnSceneMetaData object, holding a map of the pixels of the scene, with the user's label as the value in the places corresponding with the user's pixels. Pixels outside the user will not contain the user's ID. ID 0 means a request for the pixels of all users. In this case, the background will get the label 0.

Parameters:

hInstance	[in] A handle to the instance
user	[in] The user for which to get the pixels
pScene	[out] XnSceneMetaData object, that holds the pixels of the user

XN_C_API XnStatus XN_C_DECL xnGetUsers	(	XnNodeHandle	hInstance,
		XnUserID *	pUsers,
		XnUInt16 *	pnUsers
	)

Get the current users.

Parameters:

hInstance	[in] A handle to the instance
pUsers	[out] Preallocated memory for the users
pnUsers	[in,out] The size of the preallocated memory. Changes to the number of users

XN_C_API XnStatus XN_C_DECL xnRegisterToUserExit	(	XnNodeHandle	hInstance,
		XnUserHandler	handler,
		void *	pCookie,
		XnCallbackHandle *	phCallback
	)

Register to when the user exits the scene (but not lost yet)

Parameters:

hInstance	[in] A handle to the instance
handler	[in] Callback to be called when a user leaves the scene
pCookie	[in] User's cookie, to be delivered to the callbacks
phCallback	[out] The handle to this callback, to allow unregistration

XN_C_API XnStatus XN_C_DECL xnRegisterToUserReEnter	(	XnNodeHandle	hInstance,
		XnUserHandler	handler,
		void *	pCookie,
		XnCallbackHandle *	phCallback
	)

Register to when a user re-enters the scene after exiting.

Parameters:

hInstance	[in] A handle to the instance
handler	[in] Callback to be called when a user leaves the scene
pCookie	[in] User's cookie, to be delivered to the callbacks
phCallback	[out] The handle to this callback, to allow unregistration

XN_C_API XnStatus XN_C_DECL xnRegisterUserCallbacks	(	XnNodeHandle	hInstance,
		XnUserHandler	NewUserCB,
		XnUserHandler	LostUserCB,
		void *	pCookie,
		XnCallbackHandle *	phCallback
	)

Register to user callbacks.

Parameters:

hInstance	[in] A handle to the instance
NewUserCB	[in] Callback to be called when a new user is identified
LostUserCB	[in] Callback to be called when an existing user is no longer identified
pCookie	[in] User's cookie, to be delivered to the callbacks
phCallback	[out] The handle to these callbacks, to allow unregistration

XN_C_API void XN_C_DECL xnUnregisterFromUserExit	(	XnNodeHandle	hInstance,
		XnCallbackHandle	hCallback
	)

Unregister from when a user exits the scene.

Parameters:

hInstance	[in] A handle to the instance
hCallback	[in] The handle received from registration

XN_C_API void XN_C_DECL xnUnregisterFromUserReEnter	(	XnNodeHandle	hInstance,
		XnCallbackHandle	hCallback
	)

Unregister from when a user re-enters the scene.

Parameters:

hInstance	[in] A handle to the instance
hCallback	[in] The handle received from registration

XN_C_API void XN_C_DECL xnUnregisterUserCallbacks	(	XnNodeHandle	hInstance,
		XnCallbackHandle	hCallback
	)

Unregister from user callbacks.

Parameters:

hInstance	[in] A handle to the instance
hCallback	[in] The handle received from registration