BACKGROUND
[0001] Various applications will display a visual representation that corresponds
to a user that the user can control through certain actions, such as selecting buttons on a
remote or moving a controller in a certain manner. The visual representation is a
computer representation that typically takes the form of a two-dimensional (2D) or threedimensional
(3D) model and is rendered in various applications, such as computer games,
video games, chats, forums, communities, instant messaging services, and the like. The
visual representation may be in the form of an avatar, a fanciful character, a cartoon image
or animal, a cursor, a hand, or the like. Many computing applications such as computer
games, multimedia applications, office applications, or the like provide a selection of
predefined animated characters that may be selected for use in the application as the user's
avatar. Typically, the animations performed by an avatar are selected from a library of
animations. Users can choose for their avatars to perform specific animations from that
library by pressing buttons or keys on a remote, for example.
SUMMARY
[0002] Disclosed herein are techniques for intelligently training an avatar to
perform animations via learning the inputs from a user. Over time, the avatar in the virtual
space may appear to become a reflection of the user in the physical space, including
reflecting aspects of the user's features, behaviors, tendencies, voice patterns, etc. For
example, a system may have a capture device that captvires data about the user in the
physical space. The system may identify the user's characteristics, tendencies, voice
patterns, behaviors, gestvires, etc. Over time, the system may learn a user's tendencies and
intelligently apply animations to the user's avatar such that the avatar behaves and
responds in accordance with the identified behaviors of the user. Thus, training an avatar
the animations to perform may comprise learning the inputs from a user and molding the
avatar to resemble the user.
[0003] The system may therefore render an avatar that resembles the user,
whether or not the user is present in the physical space. In an example embodiment, the
animations applied to the avatar may be animations selected from a library of prepackaged
animations, such as those that come with a program, application, or a system, for
example. The animations selected may be those which correspond to the user's inputs
learned by the system. In another example embodiment, the animations in the library may
be animations entered and recorded by the user into the avatar's animation vocabulary.
For example, the system or the user may reprogram an animation to reflect the user's
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actual motions or behaviors, captured by a capture device for example. Thus, animations
may be added to or overwritten in the library of avatar animations.
[0004] This Summary is provided to introduce a selection of concepts in a
simplified form that are further described below in the Detailed Description. This
Summary is not intended to identify key features or essential features of the claimed
subject matter, nor is it intended to be used to limit the scope of the claimed subject
matter. Furthermore, the claimed subject matter is not limited to implementations that
solve any or all disadvantages noted in any part of this disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The systems, methods, and computer readable media for modifying a
visual representation in accordance with this specification are further described with
reference to the accompanying drawings in which:
[0006] FIG. 1 illustrates an example embodiment of a target recognition,
analysis, and tracking system with a user playing a game.
[0007] FIG. 2 illustrates an example embodiment of a capture device that may be
used in a target recognition, analysis, and tracking system and incorporate chaining and
animation blending techniques.
[0008] FIG. 3 illustrates an example embodiment of a computing environment in
which the animation techniques described herein may be embodied.
[0009] FIG. 4 illustrates another example embodiment of a computing
environment in which the animation techniques described herein may be embodied.
[0010] FIG. 5A illustrates a skeletal mapping of a user that has been generated
from a depth image.
[0011] FIG. 5B illustrates further details of the gesture recognizer architecture
shown in FIG. 2.
[0012] FIGs. 6A and 6B depict an example target recognition, analysis, and
tracking system and example embodiments for displaying a user's avatar based on a
history of inputs by that user.
[0013] FIG. 7A depicts two users interacting with each other remotely via their
respective target, recognition, and tracking systems. FIG. 7B depicts a first user
interacting with a second user's avatar where the second user is absent from the scene.
[0014] FIG. 8 depicts an example flow diagram for a method of collecting
behavioral data with respect to a user's inputs.
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[0015] FIG. 9 depicts an example flow diagram for a method of intelligently
applying animations to a user's avatar.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0016] Disclosed herein are techniques for rendering a visual representation of a
user, such as an avatar, that behaves in accordance with a user. For example, systems and
methods are disclosed that comprise intelligently training an avatar to perform animations
by learning a user's tendencies through user inputs. The visual representation of the user
may be in the form of an avatar, a cursor on the screen, a hand, or the any other virtual
object that corresponds to the user in the physical space. A computing system can model
and display a visual representation of the user by capturing data from a physical space.
For example, the system may comprise a capture device that captures image data of a
scene and a monitor that displays a visual representation that corresponds to a user in the
scene. It may be desirable to initialize and/or customize a visual representation based on
physical characteristics of the user. For example, the capture device may identify physical
features of a user and customize the user's avatar based on those identified features, such
as eye shape, nose shape, clothing, accessories.
[0017] To generate a model representative of a the user in the physical space, the
capture device can capture a depth image of the scene and scan targets or objects in the
scene. In one embodiment, the capture device may determine whether one or more targets
or objects in the scene corresponds to a human target such as the user. To determine
whether a target or object in the scene corresponds a human target, each of the targets may
be flood filled and compared to a pattern of a human body model. Each target or object
that matches the human body model may then be scanned to generate a skeletal model
associated therewith. For example, a target identified as a human may be scanned to
generate a skeletal model associated therewith. The model of the user, such as a skeletal
or mesh model, may represent the user's body type, bone structure, height, weight, or the
like. The model may then be provided to the computing envirormient for tracking the
model and rendering an avatar associated vnth the model.
[0018] The system may track the user and any motion in the physical space and
identify characteristics of the user that can be applied to the user's visual representation.
The identified characteristics may be indicative of the user's behaviors. For example, the
system may identify the user's physical characteristics, tendencies, voice patterns,
gestures, etc. The system may continue to track the user over time and apply
modifications or updates to the user's avatar based on the history of the tracked data. For
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example, the capture device may continue to identify behaviors and mannerisms,
emotions, speech patterns, or the like, of a user and apply these to the user's avatar. The
fidelity of the rendered avatar, with respect to the resemblance of the avatar to the avatar,
increases over time as the system gathers history data for that user.
[0019] The system, methods, and components of avatar creation and
customization described herein may be embodied in a multi-media console, such as a
gaming console, or in any other computing device in which it is desired to display a visual
representation of a target, including, by way of example and without any intended
limitation, satellite receivers, set top boxes, arcade games, personal computers (PCs),
portable telephones, personal digital assistants (PDAs), and other hand-held devices.
[0020] FIGs. lA and IB illustrate an example embodiment of a configuration of
a target recognition, analysis, and tracking system 10 that may employ techniques tracking
a history of user inputs to generate an avatar that resembles the user. In the example
embodiment, a user 18 playing a boxing game. In an example embodiment, the system 10
may recognize, analyze, and/or track a human target such as the user 18. The system 10
may gather information related to the user's gestures in the physical space, as well as the
user's physical features and behavioral characteristics.
[0021] As shown in FIG. lA, the target recognition, analysis, and tracking
system 10 may include a computing enviroiraient 12. The computing environment 12 may
be a computer, a gaming system or console, or the like. According to an example
embodiment, the computing environment 12 may include hardware components and/or
software components such that the computing enviroimient 12 may be used to execute
applications such as gaming applications, non-gaming applications, or the like.
[0022] As shown in FIG. lA, the target recognition, analysis, and tracking
system 10 may further include a capture device 20. The capture device 20 may be, for
example, a camera that may be used to visually monitor one or more users, such as the
user 18, such that gestures performed by the one or more users may be captured, analyzed,
and tracked to perform one or more controls or actions within an application, as will be
described in more detail below.
[0023] According to one embodiment, the target recognition, analysis, and
tracking system 10 may be cormected to an audiovisual device 16 such as a television, a
monitor, a high-definition television (HDTV), or the like that may provide game or
application visuals and/or audio to a user such as the user 18. For example, the computing
enviroimient 12 may include a video adapter such as a graphics card and/or an audio
5
adapter such as a sound card that may provide audiovisual signals associated vdth the
game application, non-game application, or the like. The audiovisual device 16 may
receive the audiovisual signals from the computing environment 12 and may then output
the game or application visuals and/or audio associated with the audiovisual signals to the
user 18. According to one embodiment, the audiovisual device 16 may be connected to
the computing envirormient 12 via, for example, an S-Video cable, a coaxial cable, an
HDMI cable, a DVI cable, a VGA cable, or the like.
[0024] As shown in FIG. 1, the target recognition, analysis, and tracking system
10 may be used to recognize, analyze, and/or track a human target such as the user 18.
The motion of the visual representation can be controlled by mapping the movement of the
visual representation to the motion of the user in the physical space. Motion in the
physical space may be a gesture that corresponds to a control in a system or application
space, such as a virtual space and/or a game space. For example, the user 18 may be
tracked using the capture device 20 such that the movements of user 18 may be interpreted
as controls that may be used to affect the application being executed by computer
environment 12. The computing envirormient may determine which controls to perform in
an application executing on the computer envirormient based on, for example, the user's
gesture, recognized and mapped to the model of the user. Thus, the user can control the
avatar's motion by making gestures in the physical space.
[0025] Captured motion may be any motion in the physical space that is captured
by the capture device, such as a camera. The captured motion could include the motion of
a target in the physical space, such as a user or an object. The captured motion may
include a gesture that translates to a control in an operating system or application. The
motion may be dynamic, such as a rurming motion, or the motion may be static, such as a
user that is posed with little or no motion.
[0026] The system 10 may translate an input to a captvire device 20 into an
animation, the input being representative of a user's motion, such that the animation is
driven by that input. Thus, the user's motions may map to an avatar 40 such that the
user's motions in the physical space are performed by the avatar 40. The user's motions
may be gestures that are applicable to a control in an application. As shown in FIGs. lA
and IB, in an example embodiment, the application executing on the computing
environment 12 may be a boxing game that the user 18 may be playing.
[0027] The capture device 20 may capture data representative of a user's
behaviors. For example, the capture device may capture characteristics that are indicative
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of the user's behaviors. Such characteristics may include the user's body position, facial
expressions, vocal commands, speech patterns, gestures, or the like. The computing
environment 12 may analyze the captured data and correlate a user's behaviors with
contextual circumstances, such as conditions of the user's enviroimient, the status of the
system or application, the success/result of the user in the application, the active or nonactive
status of the user, or any other detectable circumstance. Thus, the system may learn
the user's behavioral tendencies, such as how the user responds to various situations.
[0028] The computing environment 12 may use the audiovisual device 16 to
provide a visual representation of a player avatar 40 that the user 18 may control with his
or her movements. The player avatar 40 may have the characteristics of the user identified
by the capture device 20, or the system 10 may use the features of a well-known boxer or
portray the physique of a professional boxer for the visual representation that maps to the
user's motions. According to an example embodiment, the computer enviroimient 12 and
the capture device 20 of the target recognition, analysis, and tracking system 10 may be
used to recognize and analyze the punch of the user 18 in physical space such that the
punch may be interpreted as a game control of the player avatar 40 in game space. For
example, as shown in FIG. IB, the user 18 may throw a punch in physical space to cause
the player avatar 40 to throw a pimch in game space. The computing enviroimient 12 may
also use the audiovisual device 16 to provide a visual representation of a boxing opponent
38 to the user 18.
[0029] Other movements by the user 18 may also be interpreted as other controls
or actions, such as controls to bob, weave, shuffle, block, jab, or throw a variety of
different power pimches. Furthermore, some movements may be interpreted as controls
that may correspond to actions other than controlling the player avatar 40. For example,
the player may use movements to end, pause, or save a game, select a level, view high
scores, communicate with a fiiend, etc. Additionally, a full range of motion of the user 18
may be available, used, and analyzed in any suitable manner to interact with an
application.
[0030] Multiple users can interact with each other fi-om remote locations. For
example, the visual representation of the boxing opponent 38 may be representative of
another user, such as a second user in the physical space with user 18 or a networked user
in a second physical space. Alternately, the system may render an avatar associated with a
user whether or not the user is present in the physical space or interacting with the
system/application. For example, a first user's avatar may be interacting with a second
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user's avatar. The first user may be present in the physical space, controlling the gestures
and movements of the first user's avatar. However, the second user associated with the
second user's avatar may not be present in the physical space. Using the history of inputs
by the second user, the system may intelligently apply animations to the second user's
avatar such that the avatar resembles the behaviors learned fi-om the second user's inputs.
The second user's avatar may resemble the second user, closely reflecting the second
user's tendencies, habits, and other characteristics applicable to the application. The first
user can therefore have an experience in the virtual world with the second user's avatar
that may be similar to the instance where the second user is physically present and
controlling the second user's avatar.
[0031] In example embodiments, the human target such as the user 18 may have
an object. In such embodiments, the user of an electronic game may be holding the object
such that the motions of the player and the object may be used to adjust and/or control
parameters of the game. For example, the motion of a player holding a racket may be
tracked and utilized for controlling an on-screen racket in an electronic sports game. In
another example embodiment, the motion of a player holding an object may be tracked
and utilized for controlling an on-screen weapon in an electronic combat game. A user's
gestures or motion may be interpreted as controls that may correspond to actions other
than controlling the player avatar 40. For example, the player may use movements to end,
pause, or save a game, select a level, view high scores, communicate wdth a fi-iend, etc.
Virtually any controllable aspect of an operating system and/or application may be
controlled by movements of the target such as the user 18.
[0032] According to other example embodiments, the target recognition,
analysis, and tracking system 10 may interpret target movements for controlling aspects of
an operating system and/or application that are outside the realm of games. The user's
gesture may be controls applicable to an operating system, non-gaming aspects of a game,
or a non-gaming application. The user's gestures may be interpreted as object
manipulation, such as controlling a user interface. For example, consider a user interface
having blades or a tabbed interface lined up vertically left to right, where the selection of
each blade or tab opens up the options for various controls within the application or the
system. The system may identify the user's hand gesture for movement of a tab, where
the user's hand in the physical space is virtually aligned v^th a tab in the application
space. The gesture, including a pause, a grabbing motion, and then a sweep of the hand to
the left, may be interpreted as the selection of a tab, and then moving it out of the way to
8
open the next tab. Similarly, the system may learn the user's behaviors from the user's
inputs throughout the execution of any type of application. The system may animate the
user's avatar to behave in accordance with the learned inputs in that application or any
other application.
[0033] FIG. 2 illustrates an example embodiment of a capture device 20 that may
be used for target recognition, analysis, and tracking, where the target can be a user or an
object. According to an example embodiment, the capture device 20 may be configured to
capture video with depth information including a depth image that may include depth
values via any suitable technique including, for example, time-of-flight, structured light,
stereo image, or the like. According to one embodiment, the capture device 20 may
organize the calculated depth information into "Z layers," or layers that may be
perpendicular to a Z axis extending from the depth camera along its line of sight.
[0034] As shown in FIG. 2, the capture device 20 may include an image camera
component 22. According to an example embodiment, the image camera component 22
may be a depth camera that may capture the depth image of a scene. The depth image
may include a two-dimensional (2-D) pixel area of the captured scene where each pixel in
the 2-D pixel area may represent a depth value such as a length or distance in, for
example, centimeters, millimeters, or the like of an object in the captured scene from the
camera.
[0035] As shown in FIG. 2, according to an example embodiment, the image
camera component 22 may include an IR light component 24, a three-dimensional (3-D)
camera 26, and an RGB camera 28 that may be used to capture the depth image of a scene.
For example, in time-of-flight analysis, the IR light component 24 of the capture device 20
may emit an infrared light onto the scene and may then use sensors (not shown) to detect
the backscattered light from the surface of one or more targets and objects in the scene
using, for example, the 3-D camera 26 and/or the RGB camera 28. In some embodiments,
pulsed infrared light may be used such that the time between an outgoing light pulse and a
corresponding incoming light pulse may be measured and used to determine a physical
distance from the capture device 20 to a particular location on the targets or objects in the
scene. Additionally, in other example embodiments, the phase of the outgoing light wave
may be compared to the phase of the incoming light wave to determine a phase shift. The
phase shift may then be used to determine a physical distance from the capture device 20
to a particular location on the targets or objects.
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[0036] According to another example embodiment, time-of-flight analysis may
be used to indirectly determine a physical distance from the capture device 20 to a
particular location on the targets or objects by analyzing the intensity of the reflected beam
of light over time via various techniques including, for example, shuttered light pulse
imaging.
[0037] In another example embodiment, the capture device 20 may use a
structured light to capture depth information. In such an analysis, patterned light (i.e., light
displayed as a known pattern such as grid pattern or a stripe pattern) may be projected
onto the scene via, for example, the IR light component 24. Upon striking the surface of
one or more targets or objects in the scene, the pattern may become deformed in response.
Such a deformation of the pattern may be captured by, for example, the 3-D camera 26
and/or the RGB camera 28 and may then be analyzed to determine a physical distance
from the capture device 20 to a particular location on the targets or objects.
[0038] According to another embodiment, the captvire device 20 may include two
or more physically separated cameras that may view a scene from different angles, to
obtain visual stereo data that may be resolved to generate depth information
[0039] The capture device 20 may ftirther include a microphone 30, or an array
of microphones. The microphone 30 may include a transducer or sensor that may receive
and convert sound into an electrical signal. According to one embodiment, the
microphone 30 may be used to reduce feedback between the capture device 20 and the
computing environment 12 in the target recognition, analysis, and tracking system 10.
Additionally, the microphone 30 may be used to receive audio signals that may also be
provided by the user to control applications such as game applications, non-game
applications, or the like that may be executed by the computing enviroimient 12.
[0040] In an example embodiment, the capture device 20 may fiirther include a
processor 32 that may be in operative communication with the image camera component
22. The processor 32 may include a standardized processor, a specialized processor, a
microprocessor, or the like that may execute instructions that may include instructions for
receiving the depth image, determining whether a suitable target may be included in the
depth image, converting the suitable target into a skeletal representation or model of the
target, or any other suitable instruction.
[0041] The capture device 20 may frirther include a memory component 34 that
may store the instructions that may be executed by the processor 32, images or frames of
images captured by the 3-d camera 26 or RGB camera 28, or any other suitable
10
information, images, or the like. According to an example embodiment, the memory
component 34 may include random access memory (RAM), read only memory (ROM),
cache. Flash memory, a hard disk, or any other suitable storage component. As shown in
FIG. 2, in one embodiment, the memory component 34 may be a separate component in
communication with the image capture component 22 and the processor 32. According to
another embodiment, the memory component 34 may be integrated into the processor 32
and/or the image capture component 22.
[0042] As shown in FIG. 2, the capture device 20 may be in communication with
the computing environment 12 via a communication link 36. The commimication link 36
may be a wired connection including, for example, a USB connection, a Firewire
connection, an Ethernet cable connection, or the like and/or a wireless connection such as
a wireless 802.11b, g, a, or n connection. According to one embodiment, the computing
environment 12 may provide a clock to the capture device 20 that may be used to
determine when to capture, for example, a scene via the communication link 36.
[0043] Additionally, the capture device 20 may provide the depth information
and images captured by, for example, the 3-D camera 26 and/or the RGB camera 28, and a
skeletal model that may be generated by the capture device 20 to the computing
envirormient 12 via the communication link 36. The computing environment 12 may then
use the skeletal model, depth information, and captured images to, for example, control an
application such as a game or word processor. For example, as shown, in FIG. 2, the
computing environment 12 may include a gestures library 192.
[0044] As shown, in FIG. 2, the computing environment 12 may include a
gestures library 192 and a gestures recognition engine 190. The gestures recognition
engine 190 may include a collection of gesture filters 191. Each filter 191 may comprise
information defining a gesture along with parameters, or metadata, for that gesture. For
instance, a throw, which comprises motion of one of the hands from behind the rear of the
body to past the fi-ont of the body, may be implemented as a gesture filter 191 comprising
information representing the movement of one of the hands of the user fi-om behind the
rear of the body to past the fi-ont of the body, as that movement would be captured by a
depth camera. Parameters may then be set for that gesture. Where the gesture is a throw,
a parameter may be a threshold velocity that the hand has to reach, a distance the hand
must travel (either absolute, or relative to the size of the user as a whole), and a confidence
rating by the recognizer engine that the gesture occurred. These parameters for the gesture
11
may vary between applications, between contexts of a single application, or within one
context of one application over time.
[0045] The data captured by the cameras 26, 28 and device 20 in the form of the
skeletal model and movements associated with it may be compared to the gesture filters
191 in the gesture library 190 to identify when a user (as represented by the skeletal
model) has performed one or more gestures. Thus, inputs to a filter such as filter 191 may
comprise things such as joint data about a user's joint position, like angles formed by the
bones that meet at the joint, RGB color data from the scene, and the rate of change of an
aspect of the user. As mentioned, parameters may be set for the gesture. Outputs from a
filter 191 may comprise things such as the confidence that a given gesture is being made,
the speed at which a gesture motion is made, and a time at which the gesture occurs.
[0046] The computing envirormient 12 may include a processor 195 that can
process the depth image to determine what targets are in a scene, such as a user 18 or an
object in the room. This can be done, for instance, by grouping together of pixels of the
depth image that share a similar distance value. The image may also be parsed to produce
a skeletal representation of the user, where features, such as joints and tissues that run
between joints are identified. There exist skeletal mapping techniques to capture a person
with a depth camera and from that determine various spots on that user's skeleton, joints
of the hand, vmsts, elbows, knees, nose, ankles, shoulders, and where the pelvis meets the
spine. Other techniques include transforming the image into a body model representation
of the person and transforming the image into a mesh model representation of the person.
[0047] In an embodiment, the processing is performed on the capture device 20
itself, and the raw image data of depth and color (where the capture device 20 comprises a
3D camera 26) values are transmitted to the computing envirormient 12 via link 36. In
another embodiment, the processing is performed by a processor 32 coupled to the camera
402 and then the parsed image data is sent to the computing environment 12. In still
another embodiment, both the raw image data and the parsed image data are sent to the
computing environment 12. The computing environment 12 may receive the parsed image
data but it may still receive the raw data for executing the current process or application.
For instance, if an image of the scene is transmitted across a computer network to another
user, the computing environment 12 may transmit the raw data for processing by another
computing environment.
[0048] The computing environment 12 may use the gestures library 192 to
interpret movements of the skeletal model and to control an application based on the
12
movements. The computing environment 12 can model and display a representation of a
user, such as in the form of an avatar or a pointer on a display, such as in a display device
193. Display device 193 may include a computer monitor, a television screen, or any
suitable display device. For example, a camera-controlled computer system may captiire
user image data and display user feedback on a television screen that maps to the user's
gestiires. The user feedback may be displayed as an avatar on the screen such as shown in
FIG. 1. The avatar's motion can be controlled directly by mapping the avatar's movement
to those of the user's movements. The user's gestures may be interpreted to control
certain aspects of the application.
[0049] According to an example embodiment, the target may be a human target
in any position such as standing or sitting, a human target with an object, two or more
human targets, one or more appendages of one or more hxmian targets or the like that may
be scanned, tracked, modeled and/or evaluated to generate a virtual screen, compare the
user to one or more stored profiles and/or to store profile information 198 about the target
in a computing environment such as computing environment 12. The profile information
198 may be in the form of user profiles, personal profiles, application profiles, system
profiles, or any other suitable method for storing data for later access. The profile
information 198 may be accessible via an application or be available system-wide, for
example. The profile information 198 may include lookup tables for loading specific user
profile information. The virtual screen may interact with an application that may be
executed by the computing environment 12 described above with respect to FIG. 1.
[0050] According to example embodiments, lookup tables may include user
specific profile information. In one embodiment, the computing enviroimient such as
computing environment 12 may include stored profile data 198 about one or more users in
lookup tables. The stored profile data 198 may include, among other things the targets
scanned or estimated body size, skeletal models, body models, voice samples or
passwords, the targets age, previous gestures, target limitations and standard usage by the
target of the system, such as, for example a tendency to sit, left or right handedness, or a
tendency to stand very near the capture device. This information may be used to
determine if there is a match between a target in a capture scene and one or more user
profiles 198 that, in one embodiment, may allow the system to adapt the virtual screen to
the user, or to adapt other elements of the computing or gaming experience according to
the profile 198.
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[0051] One or more personal profiles 198 may be stored in computer
environment 12 and used in a number of user sessions, or one or more personal profiles
may be created for a single session only. Users may have the option of establishing a
profile where they may provide information to the system such as a voice or body scan,
age, personal preferences, right or left handedness, an avatar, a name or the like. Personal
profiles may also be provided for "guests" who do not provide any information to the
system beyond stepping into the capture space. A temporary personal profile may be
established for one or more guests. At the end of a guest session, the guest personal
profile may be stored or deleted.
[0052] As shown, in FIG. 2, the computing envirormient 12 may include an
avatar library 196 that comprises animations selectable for application to the user's avatar.
The user profile 198 may include an avatar library or otherwise associated with an avatar
library with animations specific to the user. The lookup tables may include the user's
behaviors and tendencies with respect to various contextual circumstances. The profile
may be use to apply animations to the user's avatar so that the avatar closely reflects the
behaviors of the user.
[0053] The animations in the avatar library may comprise any characteristic that
may be applied to an avatar. The characteristics may be indicative of a user's behavior.
Thus, the animation selected for application to the user's behavior may be selected to
correspond to the user's behaviors. The animations may include any one of or any
combination of voice or speech patterns, vocabulary, noise volumes, words, physical
characteristics, movements, or the like. The animations may comprise motion that may be
dynamic, such as a running motion, or the motion may be static, such as a pose with little
or no motion. The avatar library may be associated to a particular user or stored in a user
profile, for example.
[0054] The animations in the avatar library 193 may be a stock library of
animations. In an example embodiment, the animations applied to the avatar may be
animated with an animations selected from a library of pre-packaged animations, such as
those that come with a program, application, or a system, for example. The animation
selected for application to the user's avatar may be that which correspond to the user's
inputs learned by the system to reflect certain behaviors. For example, the system may
identify that the user tends to jump up and down in a certain context, such as when
achieving success in a game application. Thus, when the system identifies a similar set of
contextual circumstances such as a similar state of the game (e.g., success), the system
14
may select an animation that reflects jumping up and down and apply the animation to the
user's avatar. The pre-carmed animations may be defined for an application or for a
system. For example, the jumping up and down animation may be applicable to a gaming
application, but an open/close file animation applied to an avatar may be the same systemwide.
[0055] The animations in the avatar library may be animations entered and
recorded by the system or the user. The system allows users to overwrite or add to the
stock library of animations. For example, the system or the user may overwrite a stock
animation to reflect the user's actual motions or behaviors, captured by a capture device
for example. Thus, animations may be added to or overwritten in the library of avatar
animations so the animations applied are tailored to the data captured with respect to a
particular user. In the example of the jumping up and down animation, the system may
rewrite the standard or default animation for jumping up and dovm by recording the user's
actual motion. Thus, the jumping up and dovm animation may applied to the user's avatar
is tailored to the user's actual motions.
[0056] The system may also store data related to the user's inputs in an avatar
library. The avatar library may comprise indications of a user's behaviors and/or the
circumstances that correspond to the behaviors. For example, the circumstances may be
contextual circumstances that indicate a context that correlates to the user's behaviors.
The contextual circumstances may include any identifiable features of the scenario that
may or may not correlate to the user's behavior. The system can track the contextual
circumstances with respect to the user's behaviors and identify correlations between the
contextual circumstances and the tendencies in the user's behaviors.
[0057] Contextual circumstances, for example, may include conditions of the
user's environment, including the user's physical or virtual environment, other users
present in the physical space, the state of the game, the resuhs in the application, the active
or non-active status of the user, or the like. Conditions of the user's environment may
comprise the physical features of the scene as captured by the capture device, such as the
colors of the walls, the furniture in the room, lighting, etc. The conditions of the user's
environment may comprise the virtual conditions of the environment, such as animations
on the screen (e.g., virtual mountains displayed in a skiing game application). The state of
the application may include any status of the application, such as if the application is
paused, the amount of time an application has been executing, the skill level required
(such as in a game application), or the like. The results in the application may be, for
15
example, if code runs through a debugger successfully, or a player in a game application
achieves success or failure in the game.
[0058] The gestures library and filter parameters may be tuned for an application
or a context of an application by a gesture tool. The system may identify and store the
contexts of the application and correlate these to the inputs by the user. Using the
contextual information, the system can correlate certain behaviors of the user with a
context. In this manner, the system intelligently can apply animations to an avatar such
that the avatar responds to contextual circumstances with similar behavior.
[0059] A context may have identifiable circumstances of the context (i.e.,
contextual circumstances) and may be a cultural context, and it may be an environmental
context. A cultural context refers to the culture of a user using a system. Different
cultures may use similar gestures to impart markedly different meanings. For instance, an
American user who wishes to tell another user to "look" or "use his eyes" may put his
index finger on his head close to the distal side of his eye. However, to an Italian user,
this gesture may be interpreted as a reference to the mafia.
[0060] Similarly, there may be different contexts, or contextual circumstances,
among different environments of a single application. Take a first-user shooter game that
involves operating a motor vehicle. While the user is on foot, making a fist with the
fingers towards the groimd and extending the fist in front and away from the body may
represent a punching gesture. While the user is in the driving context, that same motion
may represent a "gear shifting" gesture. With respect to modifications to the visual
representation, different gestures may trigger different modifications depending on the
environment. A different modification trigger gesture could be used for entry into an
application-specific modification mode versus a system-wide modification mode. Each
modification mode may be packaged with an independent set of gestures that correspond
to the modification mode, entered into as a result of the modification trigger gesture. For
example, in a bowling game, a swinging arm motion may be a gesture identified as
swinging a bowling ball for release down a virtual bowling alley. However, in another
application, the swinging arm motion may be a gesture identified as a request to lengthen
the arm of the user's avatar displayed on the screen. There may also be one or more menu
environments, where the user can save his game, select among his character's equipment
or perform similar actions that do not comprise direct game-play. In that environment,
this same gesture may have a third meaning, such as to select something or to advance to
another screen.
16
[0061] The avatar libraries, including an avatar library that corresponds to a
particular user or an avatar library that is pre-packed with an application, may be
accessible for an application, across applications, or system-wide. For example, the
system may identify the user's behaviors throughout various applications. The system
may collect all of the data related to the user's behaviors across applications and store
them in a universally-acceptable avatar library. The system may then access the avatar
library and apply animations from the avatar library to the avatar under any circumstance.
[0062] A gesture may be recognized as a request for modifying animations in an
avatar library. A plurality of gestures may each represent a request to modify a particular
animation. The system can prompt the user to perform the desired motion for the
particular animation. Thus, a user can actively modify an avatar library that may be
associated with the user by making a gesture in the physical space that is recognized as a
modification gesture. For example, as described above, the user's motion may be
compared to a gesture filter, such as gesture filter 191 from FIG. 2. The gesture fiher 191
may comprise information for a modification gesture from the modifications gestures 196
in the gestures library 192.
[0063] Gestures may be grouped together into genre packages of complimentary
gestures that are likely to be used by an application in that genre. Complimentary gestures
- either complimentary as in those that are commonly used together, or complimentary as
in a change in a parameter of one will change a parameter of another - may be grouped
together into genre packages. These packages may be provided to an application, which
may select at least one. The application may tune, or modify, the parameter of a gesture or
gesture filter 191 to best fit the unique aspects of the application. When that parameter is
tuned, a second, complimentary parameter (in the inter-dependent sense) of either the
gesture or a second gesture is also tuned such that the parameters remain complimentary.
Genre packages for video games may include genres such as first-user shooter, action,
driving, and sports.
[0064] The gestures library 192, gestures recognition engine 190, avatar library
196, and profile 198 may be implemented in hardware, software or a combination of both.
For example, the gestures library 192, and gestures recognition engine 190 may be
implemented as software that executes on a processor, such as processor 195, of the
computing environment 12 (or on processing unit 101 of FIG. 3 or processing unit 259 of
FIG. 4).
17
[0065] It is emphasized that the block diagram depicted in FIGs. 2 and FIGs. 3-4
described below are exemplary and not intended to imply a specific implementation.
Thus, the processor 195 or 32 in FIG. 1, the processing unit 101 of FIG. 3, and the
processing unit 259 of FIG. 4, can be implemented as a single processor or multiple
processors. Multiple processors can be distributed or centrally located. For example, the
gestures library 190 may be implemented as software that executes on the processor 32 of
the capture device or it may be implemented as software that executes on the processor
195 in the computing environment 12. Any combination of processors that are suitable for
performing the techniques disclosed herein are contemplated. Multiple processors can
communicate wirelessly, via hard wire, or a combination thereof.
[0066] Furthermore, as used herein, a computing environment 12 may refer to a
single computing device or to a computing system. The computing environment may
include non-computing components. The computing envirormient may include a display
device, such as display device 193 shown in FIG. 2. A display device may be an entity
separate but coupled to the computing environment or the display device may be the
computing device that processes and displays, for example. Thus, a computing system,
computing device, computing environment, computer, processor, or other computing
component may be used interchangeably.
[0067] FIG. 3 illustrates an example embodiment of a computing environment
that may be used to interpret one or more gestures in a target recognition, analysis, and
tracking system. The computing envirormient such as the computing environment 12
described above with respect to FIGs. lA-2 may be a multimedia console 100, such as a
gaming console. As shown in FIG. 3, the multimedia console 100 has a central processing
unit (CPU) 101 having a level 1 cache 102, a level 2 cache 104, and a flash ROM (Read
Only Memory) 106. The level 1 cache 102 and a level 2 cache 104 temporarily store data
and hence reduce the nimiber of memory access cycles, thereby improving processing
speed and throughput. The CPU 101 may be provided having more than one core, and
thus, additional level 1 and level 2 caches 102 and 104. The flash ROM 106 may store
executable code that is loaded during an initial phase of a boot process when the
multimedia console 100 is powered ON.
[0068] A graphics processing unit (GPU) 108 and a video encoder/video codec
(coder/decoder) 114 form a video processing pipeline for high speed and high resolution
graphics processing. Data is carried from the graphics processing unit 108 to the video
encoder/video codec 114 via a bus. The video processing pipeline outputs data to an AA'^
18
(audio/video) port 140 for transmission to a television or other display. A memory
controller 110 is connected to the GPU 108 to facilitate processor access to various types
of memory 112, such as, but not limited to, a RAM (Random Access Memory).
[0069] The multimedia console 100 includes an 1/0 controller 120, a system
management controller 122, an audio processing unit 123, a network interface controller
124, a first USB host controller 126, a second USB controller 128 and a front panel I/O
subassembly 130 that are preferably implemented on a module 118. The USB controllers
126 and 128 serve as hosts for peripheral controllers 142(1)-142(2), a wireless adapter
148, and an external memory device 146 (e.g., flash memory, external CD/DVD ROM
drive, removable media, etc.). The network interface 124 and/or wireless adapter 148
provide access to a network (e.g., the Internet, home network, etc.) and may be any of a
wide variety of various wired or wireless adapter components including an Ethernet card,
a modem, a Bluetooth module, a cable modem, and the like.
[0070] System memory 143 is provided to store application data that is loaded
during the boot process. A media drive 144 is provided and may comprise a DVD/CD
drive, hard drive, or other removable media drive, etc. The media drive 144 may be
internal or external to the multimedia console 100. Application data may be accessed via
the media drive 144 for execution, playback, etc. by the multimedia console 100. The
media drive 144 is connected to the I/O controller 120 via a bus, such as a Serial ATA bus
or other high speed connection (e.g., IEEE 1394).
[0071] The system management controller 122 provides a variety of service
functions related to assuring availability of the multimedia console 100. The audio
processing unit 123 and an audio codec 132 form a corresponding audio processing
pipeline with high fidelity and stereo processing. Audio data is carried between the audio
processing unit 123 and the audio codec 132 via a communication link. The audio
processing pipeline outputs data to the A/V port 140 for reproduction by an external audio
player or device having audio capabilities.
[0072] The front panel I/O subassembly 130 supports the functionality of the
power button 150 and the eject button 152, as well as any LEDs (light emitting diodes) or
other indicators exposed on the outer surface of the multimedia console 100. A system
power supply module 136 provides power to the components of the multimedia console
100. A fan 138 cools the circuitry within the multimedia console 100.
[0073] The CPU 101, GPU 108, memory controller 110, and various other
components within the multimedia console 100 are interconnected via one or more buses,
19
including serial and parallel buses, a memory bus, a peripheral bus, and a processor or
local bus using any of a variety of bus architectures. By way of example, such
architectures can include a Peripheral Component Interconnects (PCI) bus, PCI-Express
bus, etc.
[0074] When the multimedia console 100 is powered ON, application data may
be loaded from the system memory 143 into memory 112 and/or caches 102, 104 and
executed on the CPU 101. The application may present a graphical user interface that
provides a consistent user experience when navigating to different media types available
on the muhimedia console 100. In operation, applications and/or other media contained
within the media drive 144 may be laimched or played from the media drive 144 to
provide additional functionalities to the muhimedia console 100.
[0075] The multimedia console 100 may be operated as a standalone system by
simply connecting the system to a television or other display. In this standalone mode, the
multimedia console 100 allows one or more users to interact with the system, watch
movies, or listen to music. However, with the integration of broadband connectivity made
available through the network interface 124 or the wireless adapter 148, the multimedia
console 100 may fiirther be operated as a participant in a larger network community.
[0076] When the multimedia console 100 is powered ON, a set amount of
hardware resources are reserved for system use by the muhimedia console operating
system. These resources may include a reservation of memory (e.g., 16MB), CPU and
GPU cycles (e.g., 5%), networking bandwidth (e.g., 8 kbs.), etc. Because these resources
are reserved at system boot time, the reserved resources do not exist from the application's
view.
[0077] In particular, the memory reservation preferably is large enough to
contain the launch kernel, concurrent system applications and drivers. The CPU
reservation is preferably constant such that if the reserved CPU usage is not used by the
system applications, an idle thread will consimie any vmused cycles.
[0078] With regard to the GPU reservation, lightweight messages generated by
the system applications (e.g., pop-ups) are displayed by using a GPU interrupt to schedule
code to render popup into an overlay. The amount of memory required for an overlay
depends on the overlay area size and the overlay preferably scales with screen resolution.
Where a full user interface is used by the concurrent system application, it is preferable to
use a resolution independent of application resolution. A scaler may be used to set this
resolution such that the need to change frequency and cause a TV resynch is eliminated.
20
[0079] After the multimedia console 100 boots and system resources are
reserved, concurrent system applications execute to provide system ftmctionalities. The
system functionalities are encapsulated in a set of system applications that execute within
the reserved system resources described above. The operating system kernel identifies
threads that are system application threads versus gaming application threads. The system
applications are preferably scheduled to run on the CPU 101 at predetermined times and
intervals in order to provide a consistent system resoiirce view to the application. The
scheduling is to minimize cache disruption for the gaming application nmning on the
console.
[0080] When a concurrent system application requires audio, audio processing is
scheduled asynchronously to the gaming application due to time sensitivity. A multimedia
console application manager (described below) controls the gaming application audio
level (e.g., mute, attenuate) when system applications are active.
[0081] Input devices (e.g., controllers 142(1) and 142(2)) are shared by gaming
applications and system applications. The input devices are not reserved resources, but are
to be switched between system applications and the gaming application such that each will
have a focus of the device. The application manager preferably controls the switching of
input stream, without knowledge the gaming application's knowledge and a driver
maintains state information regarding focus switches. The cameras 26, 28 and capture
device 20 may define additional input devices for the console 100.
[0082] FIG. 4 illustrates another example embodiment of a computing
environment 220 that may be the computing environment 12 shown in FIGs. 1A-2 used to
interpret one or more gestures in a target recognition, analysis, and tracking system. The
computing system enviroimient 220 is only one example of a suitable computing
environment and is not intended to suggest any limitation as to the scope of use or
functionality of the presently disclosed subject matter. Neither should the computing
environment 220 be interpreted as having any dependency or requirement relating to any
one or combination of components illustrated in the exemplary operating environment
220. In some embodiments the various depicted computing elements may include
circuitry configured to instantiate specific aspects of the present disclosure. For example,
the term circuitry used in the disclosure can include specialized hardware components
configured to perform function(s) by firmware or switches. In other examples
embodiments the term circuitry can include a general purpose processing imit, memory,
etc., configured by software instructions that embody logic operable to perform
21
fimction(s). In example embodiments where circuitry includes a combination of hardware
and software, an implementer may write source code embodying logic and the source code
can be compiled into machine readable code that can be processed by the general purpose
processing unit. Since one skilled in the art can appreciate that the state of the art has
evolved to a point where there is little difference between hardware, software, or a
combination of hardware/software, the selection of hardware versus software to effectuate
specific fimctions is a design choice left to an implementer. More specifically, one of skill
in the art can appreciate that a software process can be transformed into an equivalent
hardware structure, and a hardware structure can itself be transformed into an equivalent
software process. Thus, the selection of a hardware implementation versus a software
implementation is one of design choice and left to the implementer.
[0083] In FIG. 4, the computing enviroimient 220 comprises a computer 241,
which typically includes a variety of computer readable media. Computer readable media
can be any available media that can be accessed by computer 241 and includes both
volatile and nonvolatile media, removable and non-removable media. The system
memory 222 includes computer storage media in the form of volatile and/or nonvolatile
memory such as read only memory (ROM) 223 and random access memory (RAM) 260.
A basic input/output system 224 (BIOS), containing the basic routines that help to transfer
information between elements within computer 241, such as during start-up, is typically
stored in ROM 223. RAM 260 typically contains data and/or program modules that are
immediately accessible to and/or presently being operated on by processing unit 259. By
way of example, and not limitation, FIG. 4 illustrates operating system 225, application
programs 226, other program modules 227, and program data 228.
[0084] The computer 241 may also include other removable/non-removable,
volatile/nonvolatile computer storage media. By way of example only, FIG. 4 illustrates a
hard disk drive 238 that reads fi-om or writes to non-removable, nonvolatile magnetic
media, a magnetic disk drive 239 that reads from or writes to a removable, nonvolatile
magnetic disk 254, and an optical disk drive 240 that reads fi-om or writes to a removable,
nonvolatile optical disk 253 such as a CD ROM or other optical media. Other
removable/non-removable, volatile/nonvolatile computer storage media that can be used in
the exemplary operating environment include, but are not limited to, magnetic tape
cassettes, flash memory cards, digital versatile disks, digital video tape, solid state RAM,
solid state ROM, and the like. The hard disk drive 238 is typically connected to the
system bus 221 through an non-removable memory interface such as interface 234, and
22
magnetic disk drive 239 and optical disk drive 240 are typically connected to the system
bus 221 by a removable memory interface, such as interface 235.
[0085] The drives and their associated computer storage media discussed above
and illustrated in FIG. 4, provide storage of computer readable instructions, data
structures, program modules and other data for the computer 241. In FIG. 4, for example,
hard disk drive 238 is illustrated as storing operating system 258, application programs
257, other program modules 256, and program data 255. Note that these components can
either be the same as or different from operating system 225, application programs 226,
other program modules 227, and program data 228. Operating system 258, application
programs 257, other program modules 256, and program data 255 are given different
numbers here to illustrate that, at a minimvmi, they are different copies. A user may enter
commands and information into the computer 241 through input devices such as a
keyboard 251 and pointing device 252, commonly referred to as a mouse, trackball or
touch pad. Other input devices (not shown) may include a microphone, joystick, game
pad, satellite dish, scanner, or the like. These and other input devices are often connected
to the processing imit 259 through a user input interface 236 that is coupled to the system
bus, but may be coimected by other interface and bus structures, such as a parallel port,
game port or a universal serial bus (USB). The cameras 26, 28 and capture device 20 may
define additional input devices for the console 100. A monitor 242 or other type of
display device is also coimected to the system bus 221 via an interface, such as a video
interface 232. In addition to the monitor, computers may also include other peripheral
output devices such as speakers 244 and printer 243, which may be connected through a
output peripheral interface 233.
[0086] The computer 241 may operate in a networked environment using logical
connections to one or more remote computers, such as a remote computer 246. The
remote computer 246 may be a personal computer, a server, a router, a network PC, a peer
device or other common network node, and typically includes many or all of the elements
described above relative to the computer 241, although only a memory storage device 247
has been illustrated in FIG. 4. The logical connections depicted in FIG. 2 include a local
area network (LAN) 245 and a wdde area network (WAN) 249, but may also include other
networks. Such networking environments are commonplace in offices, enterprise-wide
computer networks, intranets and the Internet.
[0087] When used in a LAN networking environment, the computer 241 is
coimected to the LAN 245 through a network interface or adapter 237. When used in a
23
WAN networking environment, the computer 241 typically includes a modem 250 or other
means for establishing commimications over the WAN 249, such as the Internet. The
modem 250, which may be internal or external, may be connected to the system bus 221
via the user input interface 236, or other appropriate mechanism. In a networked
envirormient, program modules depicted relative to the computer 241, or portions thereof,
may be stored in the remote memory storage device. By way of example, and not
limitation, FIG. 4 illustrates remote application programs 248 as residing on memory
device 247. It will be appreciated that the network cormections shown are exemplary and
other means of establishing a communications link between the computers may be used.
[0088] The computer readable storage medium may comprise computer readable
instructions for modifying a visual representation. The instructions may comprise
instructions for rendering the visual representation, receiving data of a scene, wherein the
data includes data representative of a user's modification gesture in a physical space, and
modifying the visual representation based on the user's modification gesture, wherein the
modification gesture is a gesture that maps to a control for modifying a characteristic of
the visual representation.
[0089] FIG. 5A depicts an example skeletal mapping of a user that may be
generated from image data captured by the capture device 20. In this embodiment, a
variety of joints and bones are identified: each hand 502, each forearm 504, each elbow
506, each bleep 508, each shoulder 510, each hip 512, each thigh 514, each knee 516, each
foreleg 518, each foot 520, the head 522, the torso 524, the top 526 and bottom 528 of the
spine, and the waist 530. Where more points are tracked, additional features may be
identified, such as the bones and joints of the fingers or toes, or individual features of the
face, such as the nose and eyes.
[0090] Through moving his body, a user may create gestures. A gesture
comprises a motion or pose by a user that may be captured as image data and parsed for
meaning. A gesture may be dynamic, comprising a motion, such as mimicking throv^ng a
ball. A gesture may be a static pose, such as holding one's crossed forearms 504 in front
of his torso 524. A gesture may also incorporate props, such as by swinging a mock
sword. A gesture may comprise more than one body part, such as clapping the hands 502
together, or a subtler motion, such as pursing one's lips.
[0091] A user's gestiires may be used for input in a general computing context.
For instance, various motions of the hands 502 or other body parts may correspond to
common system wide tasks such as navigate up or down in a hierarchical list, open a file,
24
close a file, and save a file. For instance, a user may hold his hand with the fingers
pointing up and the palm facing the capture device 20. He may then close his fingers
towards the palm to make a fist, and this could be a gesture that indicates that the focused
window in a window-based user-interface computing enviroimient should be closed.
Gestures may also be used in a video-game-specific context, depending on the game. For
instance, with a driving game, various motions of the hands 502 and feet 520 may
correspond to steering a vehicle in a direction, shifting gears, accelerating, and braking.
Thus, a gesture may indicate a wide variety of motions that map to a displayed user
representation, and in a wide variety of applications, such as video games, text editors,
word processing, data management, etc.
[0092] A user may generate a gesture that corresponds to walking or miming, by
walking or running in place himself For example, the user may alternately lift and drop
each leg 512-520 to mimic walking without moving. The system may parse this gesture
by analyzing each hip 512 and each thigh 514. A step may be recognized when one hipthigh
angle (as measured relative to a vertical line, wherein a standing leg has a hip-thigh
angle of 0°, and a forward horizontally extended leg has a hip-thigh angle of 90°) exceeds
a certain threshold relative to the other thigh. A walk or run may be recognized after some
number of consecutive steps by alternating legs. The time between the two most recent
steps may be thought of as a period. After some number of periods where that threshold
angle is not met, the system may determine that the walk or running gesture has ceased.
[0093] Given a "walk or run" gesture, an application may set values for
parameters associated with this gesture. These parameters may include the above
threshold angle, the number of steps required to initiate a walk or run gesture, a number of
periods where no step occurs to end the gesture, and a threshold period that determines
whether the gesture is a walk or a run. A fast period may correspond to a nm, as the user
will be moving his legs quickly, and a slower period may correspond to a walk.
[0094] A gesture may be associated with a set of default parameters at first that
the application may override with its own parameters. In this scenario, an application is
not forced to provide parameters, but may instead use a set of default parameters that
allow the gesture to be recognized in the absence of application-defined parameters.
Information related to the gesture may be stored for purposes of pre-canned animation.
[0095] There are a variety of outputs that may be associated with the gestiare.
There may be a baseline "yes or no" as to whether a gesture is occurring. There also may
be a confidence level, which corresponds to the likelihood that the user's tracked
25
movement corresponds to the gesture. This could be a linear scale that ranges over
floating point numbers between 0 and 1, inclusive. Wherein an application receiving this
gesture information cannot accept false-positives as input, it may use only those
recognized gestures that have a high confidence level, such as at least.95. Where an
application must recognize every instance of the gesture, even at the cost of falsepositives,
it may use gestures that have at least a much lower confidence level, such as
those merely greater than.2. The gesture may have an output for the time between the two
most recent steps, and where only a first step has been registered, this may be set to a
reserved value, such as -1 (since the time between any two steps must be positive). The
gesture may also have an output for the highest thigh angle reached during the most recent
step.
[0096] Another exemplary gesture is a "heel lift jimip." In this, a user may
create the gesture by raising his heels off the ground, but keeping his toes planted.
Alternatively, the user may jump into the air where his feet 520 leave the ground entirely.
The system may parse the skeleton for this gesture by analyzing the angle relation of the
shoulders 510, hips 512 and knees 516 to see if they are in a position of alignment equal to
standing up straight. Then these points and upper 526 and lower 528 spine points may be
monitored for any upward acceleration. A sufficient combination of acceleration may
trigger a jump gesture. A sufficient combination of acceleration with a particular gesture
may satisfy the parameters of a transition point.
[0097] Given this "heel lift jimip" gesture, an application may set values for
parameters associated with this gesture. The parameters may include the above
acceleration threshold, which determines how fast some combination of the user's
shoulders 510, hips 512 and knees 516 must move upward to trigger the gesture, as well as
a maximum angle of alignment between the shoulders 510, hips 512 and knees 516 at
which a jump may still be triggered. The outputs may comprise a confidence level, as
well as the user's body angle at the time of the jump.
[0098] Setting parameters for a gesture based on the particulars of the application
that will receive the gesture is important in accurately identifying gestures. Properly
identifying gestures and the intent of a user greatly helps in creating a positive user
experience.
[0099] An application may set values for parameters associated with various
transition points to identify the points at which to use pre-canned animations. Transition
points may be defined by various parameters, such as the identification of a particular
26
gesture, a velocity, an angle of a target or object, or any combination thereof. If a
transition point is defined at least in part by the identification of a particular gesture, then
properly identifying gestures assists to increase the confidence level that the parameters of
a transition point have been met.
[0100] Another parameter to a gesture may be a distance moved. Where a user's
gestures control the actions of an avatar in a virtual environment, that avatar may be arm's
length fi-om a ball. If the user wishes to interact with the ball and grab it, this may require
the user to extend his arm 502-510 to full length while making the grab gesture. In this
situation, a similar grab gesture where the user only partially extends his arm 502-510 may
not achieve the result of interacting with the ball. Likewise, a parameter of a transition
point could be the identification of the grab gesture, where if the user only partially
extends his arm 502-510, thereby not achieving the resuh of interacting with the ball, the
user's gesture also will not meet the parameters of the transition point.
[0101] A gesture or a portion thereof may have as a parameter a volxmie of space
in which it must occur. This volxmie of space may typically be expressed in relation to the
body where a gesture comprises body movement. For instance, a football throwing
gesture for a right-handed user may be recognized only in the volume of space no lower
than the right shoulder 510a, and on the same side of the head 522 as the throwing arm
502a-310a. It may not be necessary to define all bounds of a volume, such as with this
throwdng gesture, where an outer bound away from the body is left undefined, and the
volume extends out indefinitely, or to the edge of scene that is being monitored.
[0102] FIG. 5B provides fiirther details of one exemplary embodiment of the
gesture recognizer engine 192 of FIG. 2. As shown, the gesture recognizer engine 190
may comprise at least one filter 519 to determine a gesture or gestures. A filter 519
comprises information defining a gesture 526 (hereinafter referred to as a "gesture"), and
may comprise at least one parameter 528, or metadata, for that gesture 526. For instance,
a throw, which comprises motion of one of the hands from behind the rear of the body to
past the front of the body, may be implemented as a gesture 526 comprising information
representing the movement of one of the hands of the user from behind the rear of the
body to past the fi-ont of the body, as that movement would be captured by the depth
camera. Parameters 528 may then be set for that gesture 526. Where the gesture 526 is a
throw, a parameter 528 may be a threshold velocity that the hand has to reach, a distance
the hand must travel (either absolute, or relative to the size of the user as a whole), and a
confidence rating by the recognizer engine 192 that the gesture 526 occurred. These
27
parameters 528 for the gestvire 526 may vary between applications, between contexts of a
single application, or within one context of one application over time.
[0103] Filters may be modular or interchangeable. In an embodiment, a filter has
a number of inputs, each of those inputs having a type, and a number of outputs, each of
those outpiJts having a type, hi this situation, a first filter may be replaced with a second
filter that has the same number and types of inputs and outputs as the first filter without
altering any other aspect of the recognizer engine 190 architecture. For instance, there
may be a first filter for driving that takes as input skeletal data and outputs a confidence
that the gesture 526 associated with the filter is occurring and an angle of steering. Where
one wishes to substitute this first driving filter with a second driving filter - perhaps
because the second driving filter is more efficient and requires fewer processing resources
- one may do so by simply replacing the first filter with the second filter so long as the
second filter has those same inputs and outputs - one input of skeletal data type, and two
outputs of confidence type and angle type.
[0104] A filter need not have a parameter 528. For instance, a "user height"
filter that returns the user's height may not allow for any parameters that may be timed.
An alternate "user height" filter may have tunable parameters - such as to whether to
account for a user's footwear, hairstyle, headwear and posture in determining the user's
height.
[0105] Inputs to a filter may comprise things such as joint data about a user's
joint position, like angles formed by the bones that meet at the joint, RGB color data fi-om
the scene, and the rate of change of an aspect of the user. Outputs fi"om a filter may
comprise things such as the confidence that a given gesture is being made, the speed at
which a gesture motion is made, and a time at which a gesture motion is made.
[0106] A context may be a cultural context, and it may be an environmental
context. A cultural context refers to the culture of a user using a system. Different
cultures may use similar gestures to impart markedly different meanings. For instance, an
American user who wishes to tell another user to "look" or "use his eyes" may put his
index finger on his head close to the distal side of his eye. However, to an Italian user,
this gesture may be interpreted as a reference to the mafia.
[0107] Similarly, there may be different contexts among different environments
of a single application. Take a first-person shooter game that involves operating a motor
vehicle. While the user is on foot, making a fist with the fingers towards the ground and
extending the fist in fi-ont and away fi-om the body may represent a punching gesture.
28
While the user is in the driving context, that same motion may represent a "gear shifting"
gestxire. There may also be one or more menu environments, where the user can save his
game, select among his character's equipment or perform similar actions that do not
comprise direct game-play. In that environment, this same gesture may have a third
meaning, such as to select something or to advance to another screen.
[0108] The gesture recognizer engine 190 may have a base recognizer engine
517 that provides functionality to a gesture filter 519. In an embodiment, the functionality
that the recognizer engine 517 implements includes an input-over-time archive that tracks
recognized gestures and other input, a Hidden Markov Model implementation (where the
modeled system is assumed to be a Markov process - one where a present state
encapsulates any past state information necessary to determine a fiiture state, so no other
past state information must be maintained for this purpose - with unknown parameters,
and hidden parameters are determined from the observable data), as well as other
functionality required to solve particular instances of gesture recognition.
[0109] Filters 519 are loaded and implemented on top of the base recognizer
engine 517 and can utilize services provided by the engine 517 to all filters 519. In an
embodiment, the base recognizer engine 517 processes received data to determine whether
it meets the requirements of any filter 519. Since these provided services, such as parsing
the input, are provided once by the base recognizer engine 517 rather than by each filter
519, such a service need only be processed once in a period of time as opposed to once per
filter 519 for that period, so the processing required to determine gestures is reduced.
[0110] An application may use the filters 519 provided by the recognizer engine
190, or it may provide its own filter 519, which plugs in to the base recognizer engine 517.
In an embodiment, all filters 519 have a common interface to enable this plug-in
characteristic. Further, all filters 519 may utilize parameters 528, so a single gesture tool
as described below may be used to debug and t\me the entire fiUer system 519.
[0111] These parameters 528 may be timed for an application or a context of an
application by a gesture tool 521. In an embodiment, the gesture tool 521 comprises a
plurality of sliders 523, each slider 523 corresponding to a parameter 528, as well as a
pictorial representation of a body 524. As a parameter 528 is adjusted with a
corresponding slider 523, the body 524 may demonstrate both actions that would be
recognized as the gesture with those parameters 528 and actions that would not be
recognized as the gesture with those parameters 528, identified as such. This visualization
29
of the parameters 528 of gestures provides an effective means to both debug and fine tune
a gesture.
[0112] FIGs. 6A and 6B depict a system 600 that may comprise a capture device
608, a computing device 610, and a display device 612. In this example, a depth camera
608 captures a scene in a physical space 601 in which a user 602 is present. For purposes
of this description, display device 612 is shown as display device 612a in FIG. 6A and as
display device 612b in FIG. 6B, and user 602 is shown as user 602a in FIG. 6A and as
user 602b in FIG. 6B. The depth camera 608 processes the depth information and/or
provides the depth information to a computer, such as computer 610. The depth
information can be interpreted for display of a visual representation of the user 602. For
example, the depth camera 608 or, as shown, a computing device 610 to which it is
coupled, may output to a display 612a, 612b. In this example, the user 602 is playing a
soccer game application.
[0113] The capture device 608, computing device 610, and display device 612a,
612b may each comprise any suitable device that performs the desired functionality, such
as the devices described with respect to FIGs. 1-5B. It is contemplated that a single device
may perform all of the functions in system 600, or any combination of suitable devices
may perform the desired functions. For example, the computing device 610 may provide
the functionality described with respect to the computing envirormient 12 shown in FIG. 2
or the computer in FIG. 3. As shown in FIG. 2, the computing environment 12 may
include the display device and a processor. The computing device 610 may also comprise
its own camera component or may be coupled to a device having a camera component,
such as capture device 608.
[0114] The visual representation of a user 602 can take any form, such as an
animation, a character, an avatar, or the like. For example, the visual representation of the
target, such as a user 602, may initially be a digital lump of clay that the user 602 can
sculpt into desired shapes and sizes, or a character representation selected fi"om a stock
library of avatars. In a baseball game application, for example, the options for visually
representing the user 602 may take any form, from a representation of a well-known
baseball player to a piece of taffy or an elephant to a fanciful character or symbol, such as
a cursor or hand symbol. The visual representation may represent a combination of the
user's 602 featwes and featvires of an animation or stock model. For example, the user 602
may select from a variety of stock models that are provided by a game application. The
system may apply features of the user to the selected stock model. The visual
30
representation may be specific to an application, such as packaged with a program, or the
visual representation may be available across-applications or available system-wide.
[0115] The example visual representation shown in FIGs. 6A and 6B, as shown
on the display device 612a, is that of an avatar 606 with featvires that resemble those of the
user 602. FIGs. 6A and 6B show the avatar 606 in two different frames or points in time,
represented by avatar 606a in FIG. 6A and as avatar 606b in FIG. 6B. Though additional
firames of image data may be captured and displayed, the fi-ames depicted in FIGs. 6A and
6B are selected for exemplary purposes. The rate that frames of image data are captured
and displayed may determine the level of continuity of the displayed motion of the visual
representation.
[0116] The system 600 may capture information about the physical space 601,
such as depth information, image information, RGB data, etc. According to one
embodiment, image data may include a depth image or an image from a depth camera 608
and/or RGB camera, or an image on any other detector. For example, camera 608 may
process the image data and use it to determine the shape, colors, and size of a target. Each
target or object that matches the human pattern may be scanned to generate a model such
as a skeletal model, a flood model, a mesh human model, or the like associated therewith.
For example, as described above, the depth information may be used to generate a skeletal
model of the user, such as that shown in FIG. 5A, where the system identifies the user's
body parts such as the head and limbs. Using, for example, the depth values in a plurality
of observed pixels that are associated with a human target and the extent of one or more
aspects of the human target such as the height, the width of the head, or the width of the
shoulders, or the like, the size of the human target may be determined.
[0117] The system 600 can track the movements of the user's limbs by analyzing
the captured data and translating it to the skeletal model. The system 600 can then track
the skeletal model and map the movement of each body part to a respective portion of the
visual representation. For example, if the user 602 waves his or her arm, the system may
capture this motion and apply it to the avatar's 606 arm such that the virtual avatar also
waves its arm. Further, the system 600 may identify a gesture from the user's motion, by
evaluating the user's position in a single jframe of capture data or over a series of fi-ames,
and apply the gesture to the visual representation.
[0118] The system can use captured data, such as scanned data, image data or
depth information to identify characteristics indicative of the user's behaviors to learn the
user's behaviors. For example, a system may have a capture device that captures data
31
about the user in the physical space. The system may identify a user's behaviors by
collecting and storing a history of data regarding characteristics indicative of the user's
behaviors, such as the user's physical features, tendencies, voice patterns, habits,
vocabulary, voice commands, voice fluctuations, responses, behaviors, gestures, etc, and
identify circimistances that may elicit certain user behaviors, such as the contextual
circumstances. The system may record or store a history of data about the contextual
circumstances associated with the user's behaviors, such as the system status, game or
application status, or any other features of the scenario. Further, the system can evaluate
the scenario and draw correlations between the contextual circumstances and the user's
behavior to determine the user's tendencies in different scenarios. For example, the
system may learn how the user's voice fluctuates under certain circumstances, or how the
user stands when the user is not an active participant in the executing application.
[0119] It may be desirable to animate the user's avatar even if actual user is not
present. For example, when the user is not in the physical space, it may be desirable to
provide an avatar that represents the user and is able to behave in accordance with the
user's behaviors (as learned by the system). Thus, the system may access the history data
and apply animations to the avatar that are indicative of the absent user's behaviors and
tendencies, even if the user is not present in the physical space. For example, the system
can apply animations to the absent user's avatar such that the absent user's avatar moves,
talks, uses language, etc, that correspond to the absent user. This allows a second user to
have a virtual experience with the absent user's avatar that would be similar to the instance
where the absent user is present and interacting with the system.
[0120] Over time, the system 600 may continue to learn a user's tendencies and
continuously update the user's avatar library with characteristics indicative of a user's
behaviors and tendencies and with contextual circumstances. The contextual
circumstances may be correlated to certain user behaviors, where the user may respond to
certain contextual circumstances in identifiable ways. The system may intelligently apply
animations to the user's avatar 606 such that the avatar 606 behaves and responds in
accordance with the behaviors of the user. As the system gathers more data from the
user's inputs, the avatar may become a closer and closer reflection of the user, having
aspects of the user's physical features, behaviors, emotions, speech patterns, tendencies,
voice patterns, etc. Thus, training an avatar the animations to perform may comprise
learning the inputs from a user and molding the avatar to resemble the user. The user may
32
not be present in the physical space but the user's avatar may become such a close
resemblance to the user that it appears that the user is present and/or controlling the avatar.
[0121] The identity of characteristics indicative of a user's behaviors may
include information that may be associated with the particular user 602 such as behavioral
tendencies, speech patterns, facial expressions, skeletal movements, words spoken, history
data, voice recognition information, or the like. The user's characteristics may comprise
physical features of the user, such as: eye size, type, and color; hair length, type, and color;
skin color; clothing and clothing colors. For example, colors may be identified based on a
corresponding RGB image. Other target characteristics for a human target may include,
for example, height and/or arm length and may be obtained based on, for example, a body
scan, a skeletal model, the extent of a user 602 on a pixel area or any other suitable
process or data. The computing system 610 may use body recognition techniques to
interpret the image data and may size and shape the visual representation of the user 602
according to the size, shape and depth of the user's 602 appendages.
[0122] The system may actively or passively learn the user's behaviors. In FIG.
6, the avatar 606 is a close physical representation of the user 602, with added features and
animations that are applicable to the soccer game application (e.g., the goal post and net
609, the ball 607, etc). The user 602 is the active player in the soccer game application
and a second user 603 is the non-active player, although both are in the physical space. As
used herein, non-active merely refers to the user 603 that is not, in this example, presently
performing gestures to control aspects of the application. More than one user may be
active at one time. Alternately, the system may allow one active user at a time. In this
example, the non-active player 603 is waiting for his or her turn, while the current player
602a is gesturing to control the avatar 606a on the display 612a.
[0123] Active user learning is learning associated with gestures or controls of the
application, and may comprise learning behaviors from either or both users 602a, 603.
Active user learning describes when a user, such as user 602 or user 603, performs specific
motions or gestures, and the system identifies characteristics indicative of the user's
behaviors associated with the user's gesture. Gestures may include dynamic or static
movement as well as voice commands, and may be performed to control aspects of the
system or an executing application. For example, in FIG. 6A, the user's 602a motion in
the physical space 601 comprises a diving motion to the left with the arms stretched out to
the left. The gesture may be recognized as a soccer goalie move and can result in
controlling the animation of the avatar 606a. The result of the gesture may be recognized
33
as a failure or success in the game (e.g., the gesture may resuh in a failure/success in the
soccer game application). The system 600 may identify aspects of the gesture itself or
behaviors that correspond to the gesture and associate those aspects or behaviors with the
user.
[0124] FIG. 6 depicts an example scenario in which the system can actively learn
a user's behaviors associated with a gesture, where the user is performing gestures in a
soccer game application. The system 600 may identify aspects of the gesture itself or
behaviors that correspond to the gesture and associate those aspects or behaviors with the
user. In this manner, the gesture data and behaviors of the user that correspond to the
gesture may be applied to an avatar such that the animations are tailored to the specific
user. In this example, the user 602 is playing the role of a soccer goalie. If the majority of
the time that the user 602 performs a goalie gesture that results in saving a ball 607 from
going into the net 609 the user also does a dance, the system may identify and correlate the
user's behaviors (e.g., the dance) with the contextual circumstances (e.g., soccer goalie
gesture and the successful result of the gesture). Thus, the system can correlate a user's
behaviors with the state of the game. In another example, if the user tends to open his
mouth when gesturing to hit a tennis ball in a tennis game application, or the user grunts
during a serving gesture in the tennis game application, the system may include
information in the gesture data that indicates other behaviors of the user that occur when
performing the gesture.
[0125] The system can store animation that corresponds to the user's behavior,
such as an animation of the user's dance. The system may store an indication in the user's
profile that the animation correlates to certain contextual circumstances, such as the
performance of the gesture and/or state of the game. Similarly, the system can identify
tendencies in a user's facial expressions, body positions, language, etc, that correlate to the
user's gesture, a state of the application, or any other identifiable contextual circumstance
(including an idle state), and indicate the correlation in the user's profile or the avatar
library, for example. In the future, when the user performs the gesture and it resuUs in a
similar state of the game (e.g., the success of saving the ball from going into the net), the
system may apply the dancing animation to the user's avatar. Similarly, if the user is not
present, the system may render the user's avatar and simulate the user's participation via
the avatar, such as applying gestures and animations associated with those gestures to the
avatar. In this example, the system may identify history data and also apply the dancing
animation to the user's avatar under the appropriate contextual circumstances. Thus, the
34
user's avatar may represent a close resemblance to the user based on history data, even if
the system is not using data captured with respect to the user in real time.
[0126] The system can passively learn a user's behaviors when the user is not
active, such as when the user is acting naturally in the physical space where the user's
behavior may not correspond to a gesture. The system can passively detect the user's
behaviors under such circumstances such as the user's tendencies, responses, idle activity,
etc. During passive learning, the system may capture data of the user when the user is
acting naturally. For example, during passive learning, the user may not be interacting
with the system, or it may be another player's turn in a game application. Passive player
training may include the system's learning how the player behaves (e.g., body position,
facial expressions, actions, words spoken, voice fluctuations), when the user is idle
throughout an experience. For example, in FIG. 6, the second user 603 in the physical
space 601 is not actively interacting with the soccer game application being played by the
first user 602. The second user 603, while idle, is seated and the user's 603 head is resting
in the user's 603 hand. The system may learn the user's habits in such scenarios and add
them to the avatar library of the user.
[0127] The system can learn any of the user's natural or idle behaviors in such
circiraistances and associate them to the user. For example, the system may identify how
the player walks and save the motion as the walking animation in the avatar library for that
user. The system can watch and listen to a user during activity under various
circumstances and scenarios that may not involve a gesture or other active control of the
system or the executing application. For example, when a user greets a friend in a remote
game playing experience, the system may detect that the user typically greets fiiends with
a typically greeting such as "Hi, buddy, how are you?" The same user may greet unknown
players with a greeting such as "Hello, my name is ..." The system may use the captured
data, including the voice fluctuations, words spoken, and any other motion, and add it to
the avatar library for the user's avatar.
[0128] The avatar library may comprise pre-packaged animations that may be
applied to an avatar to represent the user's gesture or any other user behavior. Through
passive learning, the system may update, add, or rewrite animations in the avatar library.
The system or user may modify aspects of the animation entirely, add, update, reprogram,
rewrite, or delete entries in the avatar library. For example, a user may not be interacting
with the system or gesturing for any control of the application. The user may be idle while
another user is active in the application. The system may apply a standard animation to
35
the user's avatar that represents idle behavior, such as animating the idle user's avatar to
sit quietly and observe the active user perform in the physical space. However, the system
may capture data related to the actual behavior of the idle user when the user is idle in the
game application. The system may record the user's behavior and add them to an entry in
the avatar library for an idle animation for that user. The system may rewrite the standard
animation for idle behavior with an animation that represents the user's behavior as
recorded by the system.
[0129] For example, the system may recognize that when user 603, shown in
FIG. 6A, is idle or non-active, the user 603 tends to place the user's head in the user's
right hand. The system may store data related to this in a profile or avatar library
associated with the user. The animation may represent an addition to the avatar library or
it may be a rewrite of a default animation for idle activity. Thereafter, the system may
apply an animation to that effect to the avatar 611, such as the animation of avatar 611
shown in FIG. 6B, where the avatar is seated with the avatar's head in the avatar's right
hand. However, over time, the system may recognize that the user 603 more often rests
his or her head in the user's left hand, or tends to switch between hands often while idle.
Thus, the system may continue to refine the avatar library and the animations in the avatar
library to more closely represent the identified tendencies of the user. The system may
also keep the original animation data and add the redefined animation to the user's avatar
library, providing multiple animations for selection.
[0130] FIG. 6B depicts the system 600 shown in FIG. 6A. FIG. 6B depicts an
example of just the user 602 in the physical space 601. In this example, the same user 602
is gesturing in the physical space 601, resulting in an animation of the user's avatar 606b
that is representative of a goalie gesture similar to that applied to the avatar 606a in FIG.
6A. However, in this example, the motion of the user 602 in the physical space is varied
from that performed by the user 602 in FIG. 6A, but the same gesture is identified and
represented by both avatars 606a and 606b.
[0131] Packages of standard gestures are gestures from which system and
application developers can incorporate gesture recognition into their systems and/or
applications. The system may modify aspects of the gesture or rewrite the gesture
entirely. For example, the system may modify a motion that corresponds to a particular
gesture by redefining the motion. For example, user 602b may be injured and unable to
dive in the physical space 601 as previously performed by the user 602a, shown in FIG.
6A. The system may recognize the user's varied motion or the user may request to modify
36
the gesture data. For example, the system may prompt a user with a basic camied gesture
or voice command as a demonstration and the user can perform the user's own version of
that gesture or voice command. To redefine the gesture, the user 602 may perform the
motion shown in FIG. 6B that comprises a standing position, leaning to the left, and
swinging the arms out to that side. The system can temporarily or permanently overwrite
the default gesture data with the user-defined gestiire data. The system may also keep the
original gesture data and add the redefined gesture to the user's avatar library, providing
multiple gestures that provide a similar result in the application. Following the
redefinition or addition of the gesture, the system may capture data with respect to the user
in the physical space and be able to determine fi-om that data whether the user has
performed the redefined or added gesture.
[0132] Similarly, active user learning may comprise identifying a user's gesture
where the gesture itself is a prompt to modify an animation in the avatar library and/or
modify the behaviors identified by the system and associated with the user. For example,
the user may initiate a modification to an animation or initiate the addition of an animation
to the avatar library by performing a gesture or entering into a modification mode of a prepackaged
animation. The system may prompt a user with a basic canned animation or
voice data as a demonstration, and the user can perform the user's own version of that
animation or provide speech samples.
[0133] For example, the system may apply an animation to the avatar 611
associated with user 603 that comprises a seated position with the avatar's head resting in
the avatar's hand, similar to that shown in FIG. 6B. The system may recognize that when
the user is idle or when the user performs a similar motion in the physical space, the user
tends to position himself or herself as shown in FIG. 6A. However, the user may wish to
modify the history data that indicates this behavior for the user when the user is idle. The
user may perform a gesture to initiate a modification of the history data and/or the
animation applied to the user's avatar under particular contextiml circumstances (e.g., idle
activity). The system may prompt a user with the current animation associated with
particular contextual circumstances, and the user can perform a different version of that
animation for rewriting the animation in the avatar library.
[0134] In both scenarios that the system or user adds, updates, or rewrites gesture
or animation data, the system may record the user's inputs and validate the redefined
gesture or animation data. For example, if the user is performing a "wave" gesture, the
system can detect that the motion corresponds to the "wave" gesture via the gesture
37
recognition engine as described above. The system may detect where the gesture starts
and stops and prompt the user to perform a new motion in the physical space to overwrite
the current "wave" gesture data and/or create an additional "wave" gesture that
corresponds to the user's recorded motion.
[0135] The system may validate the user's recorded motion. For example, in a
game application that is identified for teenagers, the system may not confirm a user's
motion for a gesture if the user's proposed motion for that gesture comprises a socially
unacceptable motion (e.g., a rude motion). Thus, the system may identify a user's
behavior that is not desirable and that should not be reflected by the user's avatar.
Consider the soccer game application where the user plays the role of the soccer goalie.
The system may identify the user's tendency to swear or make obscene gestures when the
user performs a goalie gesture and the result is a failure (i.e., the ball goes into the net).
Thus, the system may select a different animation to apply to the avatar under these
contextual circumstances, such as a user-specific animation fi-om the user's avatar library
or a generic animation fi-om a generic avatar library. When the system identifies the
goalie gesture and the state of the game (e.g., failure to save the ball), the system may be
tuned to apply a non-obscene animation to the avatar rather than the avatar mimicking the
motions made by the user in the physical space. Similarly, the system may invalidate the
behavior and not include it as an animation in the avatar library from which to choose
when applying animations to the user's avatar. Thus, some behaviors or indications of
such behaviors may not be stored for later use.
[0136] FIG. 6B depicts an example where the system may apply the user's
behaviors and tendencies to the avatar, whether or not the user is actually in the physical
space. In FIG. 6B, the avatar 611 represents the user 603 fi-om FIG. 6A. However, user
603 is no longer in the physical space 601 in FIG. 6B. It may be desirable, when the user
is not in the physical space, to provide an avatar that represents the user and is able to
behave in accordance with the user's behaviors (as learned by the system). For example,
the system may continue to display the user's avatar and apply animations to the user's
avatar that correspond to the user's tendencies and behaviors, even if the user leaves the
room and is no longer within tracking view of the system. Consider a game application,
where a first user selects to play a game against a second user, but that second user may or
may not be in the physical space. The system can mimic the second user, reflecting the
user's physical characteristics, tendencies, behaviors, and other characteristics, based on a
profile of that second user. The second user's abilities can be mimicked, for example, if a
38
skill level is applicable to the application. Thus, the first user can have an experience with
the second user's avatar that would be similar to the instance when the second user is
actually in the physical space and/or interacting with the system. The system can apply
animations to the second user's avatar such that the second user's avatar moves, talks, uses
language, etc, that correspond to the second user.
[0137] The behaviors of the user 603 may be identified fi-om the user's prior
inputs and/or the data captured by the system, over time, with respect to the user 603. The
avatar increasingly reflects aspects of the user in the physical space, including aspects
related to the user's features, behaviors, tendencies, voice patterns, etc. For example, the
system may learn a user's tendencies and intelligently apply animations to the user's
avatar such that the avatar behaves and responds in accordance with the identified
tendencies of the user. Thus, training an avatar the animations to perform may comprise
learning fi-om the history of inputs from a user and molding the avatar to resemble the
user.
[0138] The system may learn how the user responds to various scenarios and
capture the status of the user's characteristics. For example, if a user is standing idle
during a game application, where another user is the active player, the system may detect
the user's body position and activities that the user may partake while not the active
player. The user may take a drink, stand idle against the wall, watch the active player or
the screen, read a book, or any other activity. For example, it may be common for the user
to read a book while not the active player. The system may recognize this tendency and
store information related to the tendency in a user's profile.
[0139] In FIG. 6A the system may have detected the user's 603 body language,
positioning, language spoken, etc, while the user 603 was observing user 602 actively
participate in the soccer game application. The system may have other history data with
respect to user 603, captured over a period of time. In FIG. 6B, the user 603 is not in the
physical space 601, however the user's avatar 611 may be displayed on the display device
612. The system may apply animations to the user's avatar 611 that correspond to the
history data gathered for the user's 603 behaviors. Thus, the system may depict the user's
avatar 611 in a seated position similar to how the user typically behaves when the nonactive
player in the game. The system may provide additional animations, such as placing
the user in seats or bleachers that might be found at a typical soccer game and may be
where typical observers of a soccer game sit.
39
[0140] The system may store data related to the user's inputs in an avatar library,
such as avatar library 196 shown in FIG. 2. The avatar library may be associated to a
particular user or stored in a user profile, such as profile 198, for example. As described
above, the system allows users to overwrite or add to the stock library of animations. In
another example embodiment, the animations in the library may be animations entered and
recorded by the user into the avatar's library. For example, the system or the user may
reprogram an animation to reflect the user's actual motions or behaviors, captured by a
capture device for example. Thus, animations may be added to or overwritten in the
library of avatar animations.
[0141] The system may also comprise a imiversal or generic avatar library that
comprises a stock library of animations. In an example embodiment, the animations
applied to the avatar may be animations selected fi-om a library of pre-packaged
animations, such as those that come with a program, application, or a system, for example.
The animations selected may be those which correspond to the user's inputs learned by the
system to reflect certain behaviors. The pre-canned animations may be defined for an
application or for a system. For example, an open/close file animation applied to an avatar
may be the same system-wide.
[0142] The avatar libraries, including an avatar library that corresponds to a user,
may be accessible for an application, across applications, or system-wide. For example,
the system may identify the user's behaviors throughout various applications. The system
may collect all of the data related to the user's behaviors across applications and store
them in a universally-acceptable avatar library. The system may then access the avatar
library and apply animations fi-om the avatar library to the avatar imder any circumstance.
For example, the system may identify that the user typically bites his or her nails when the
user is not the active player in a game. Thus, when the user is interacting with the system
during the execution of a non-game application, the system may apply an animation of
nail-biting to the user's avatar when there are delays in user interaction with the
application, such as when the user is waiting for a document to save or for a debugger to
run on software.
[0143] The system may display a user's avatar at any time and at any time apply
animations to the avatar that reflect the user's behavior. Over time, the system may apply
animations of the user any type of scenario v^dth or without assistance ftom the user. For
example, using the avatar library and stored data associated with a user's behaviors, the
system can generate a voice mail message using the user's identified voice patterns and
40
volumes without input from the user. The system could mimic the user's behaviors when
applying animations to an avatar in an application's dashboard, in communication with
friends, in game applications, or the like. The user may or may not be controlling the
avatar - rather, the system may be providing the likeness of the user's avatar. The system
may apply animations to an avatar associated with a particular user, whether or not the
particular user is present in the physical space. For example, the user could be writing a
document in a word processing application and the system could display and animate an
avatar on the screen that resembles the user. The system could apply animations from the
user's avatar library.
[0144] The system may identify that the user behaves differently between
applications or across different enviromnents. For example, in a game application, the
user may watch and observe the display and/or the other user when the other user is the
active player in the game. However, in a non-game application, the user may not observe
the screen when another user is active or if the application is saving a document or running
a debugger, for example. The user may bite his or her nails or leave the room.
[0145] The avatar may be displayed, even if the avatar is not necessary to the
application for controlling any aspect of the application or the system. An avatar may be
displayed, performing and behaving as learned from the user's inputs, typically learned by
the system following a series of inputs that are sufficient to identify behaviors, responses,
tendencies, or the like. For example, a first user may be telling a story in the physical
space and select an avatar to be displayed on screen to animate the story as it is being told.
The avatar selected may be an avatar associated with a user that is not present in the
physical space. However, the system may have enough information stored with respect to
the user that is not present to animate the avatar such that it appears to behave like the user
that is not present. The system could use the avatar that comes with an avatar library full
of animations that correspond to the user's behaviors that the system has learned over
time. Thus, it could appear that the user is present and providing inputs because the avatar
is able to represent the user so well.
[0146] As described, the system 600 may identify data from the physical space
that are indicative of the user's behaviors. For example, the system 600 may gather
information related to the user's motions, facial expressions, body language, emotions, etc,
in the physical space. The system may use body posture recognition techniques to assist
in the identity of the emotions or temperament of the himian target. For example, the
system 600 may analyze and track a skeletal model of the user to determine how the user
41
moves. The system 600 may track the user's body and the motions made by the user's
body, including gestures that control aspects of the system, such as the application,
operating system, or the like. The system may identify the user's body posture, facial
expressions, vocal expressions and tone, directed gazes, etc. The user's vocal expressions
may provide an indication of the user's temperament. For example, the langiiage used, the
tone of voice, the pitch, volimie, and the like may convey a sense of the user's
temperament. For example, a harsh tone may be interpreted as anger or aggression. Other
tones may be tense, modal, breathy, whispery, creaky, calm, excited, happy, or any other
tone. The system may identify the user's facial movements, such as the movement of the
user's eyebrows and/or a frowning or smiling expression. The system may detect words
said by the user and the user's tone of voice, or the user's body position, etc. For example,
the system may detect the right arm of a person and have the fidelity to distinguish the
upper arm, lower arm, fingers, the thumb, joints in the fingers, etc. Thus, the user's
characteristics are good indicators of the user's behaviors and tendencies.
[0147] In the example shown in FIG. 6A, the user 603 is sitting with a head tilted
to the side, a right elbow resting on the knee, and the head being supported by the user's
right hand. The user's facial expressions, body position, words spoken, or any other
detectable characteristic may be applied to the user's avatar 611, and modified if
appropriate. For example, the user 603 is seated in a chair, but the system modifies the
user to be seated in bleachers or seats that might be found at a soccer game.
[0148] The system 600 may compare the circumstances of the application with a
user's avatar library to determine what animations should be applied to the user's visual
representation. For example, in the soccer game application described above, the state of
the game may be the user's success in saving a ball. The system may apply the animation
of the user's dance to the avatar as the system has identified this behavior as typical for
this user under these circimistances. In another example, where a first user is present in
the physical space and telling a story with the avatar for a second user selected for acting
out the story on the display. The second user may or may not be present, but the avatar
may act out the story on the display, reflecting the behaviors identified for the second user.
For example, the story may describe a person jumping over a creek. The avatar, that
resembles the second user, may be shown jumping over a creek, but animated to appear
like the second user, reflecting the behavior's of the second user. For example, the system
may identify behaviors of the user that are typical when a user is jumping, or when a user
42
is scared, or having fun. The system may apply animations to the avatar that correspond
to the circumstance and the data stored about the user's behaviors in such circumstances.
[0149] FIG. 7A depicts an example of two users remotely playing against each
other in a boxing game application. The remote users interact with a target recognition,
analysis, mid tracking system 10 in their respective physical space, and are able to interact
with each other over a network coimection. Each system can provides live visual feedback
of each physical space to the other system. In FIG. 7A, two users, User #1 and User #2,
are interacting with the system executing the boxing game application. Thus, each system
may capture live data with respect to each user and render the visual representation that
corresponds to each user and maps to the motion of each user. In FIG. 7B, the second user
is no longer present in the physical space and is absent from the tracking view of the target
recognition, analysis, and tracking system. However, the system has collected data with
respect to the user's behaviors, either in this instance of the boxing game application, prior
instances, or in any other interaction by the user with the system or an application. The
system is able to apply animations from an avatar library associated with the user that
reflect the user's behaviors. Thus, based on the history of the user's inputs, the system is
able to render a visual representation that appears very similar to the user. User #1 can
have an experience with the second user's avatar that would be similar to the instance
where actual user data were applied to the avatar.
[0150] FIG. 8 shows an example method of learning a user's behaviors and FIG.
9 shows an example method of applying animations of select behaviors to the user's
avatar. For example, at 802, the system receives data from a physical space that includes a
user. As described above, a capture device can capture data of a scene, such as the depth
image of the scene and scan targets in the scene. The capture device may determine
whether one or more targets in the scene correspond to a human target such as a user.
Each target or object that matches the human body model may then be scaimed to generate
a skeletal model associated therewith. The skeletal model may then be provided to the
computing environment for tracking the skeletal model and rendering a visual
representation associated with the skeletal model.
[0151] At 804, the system may identify characteristics indicative of the user's
behaviors. The characteristics indicative of the user's behavior may comprise physical
characteristics, facial features, speech patterns, vocabulary, voice commands, a gesture,
motion, or body position. For example, the system may use body recognition and facial
recognition techniques to identify body and facial characteristics. The user's behaviors,
43
that may include certain facial expressions and body movements, may be identified. For
example, a system may have a capture device that captures data about the user in the
physical space. The system may identify the user's characteristics, tendencies, voice
patterns, behaviors, gestures, etc. The system may identify characteristics indicative of a
user's behavior passively and/or actively. For example, passive learning may comprise
identifying the user's characteristics when the user is acting naturally in the physical
space, and active learning may comprise identifying the user's characteristics when the
user is performing a gesture. Over time, the system may learn a user's tendencies and
intelligently apply animations to the user's avatar such that the avatar behaves and
responds in accordance with the identified tendencies of the user. Thus, training an avatar
the animations to perform may comprise learning the inputs from a user and molding the
avatar to resemble the user.
[0152] At 805, the system may add or rewrite an animation in a pre-packaged
avatar library. For example, the pre-packaged avatar library may be a default set of
animations provided with an application. Rewriting an animation in the pre-packaged
avatar library may comprise updating the animation to correspond to a history of the
characteristics indicative of the user's behavior, as stored at 808. Adding an animation to
the pre-packaged avatar library may comprise recording a user's motion in the physical
space and adding an animation representative of the user's motion to the avatar library.
The adding to or rewriting an animation in the avatar library may be prompted by a user's
gesture. For example, the user may perform a gesture to enter into a modification mode,
and the system can record the user's motions in the modification mode and apply them to
the added or rewritten animation.
[0153] At 806, the system may generate an animation and add it to an avatar
library. The avatar library may or may not be pre-packaged. For example, the avatar
library may comprise animations recorded by the user and may or may not be provided by
the system. Thus, the user may define all the animations in the avatar library that are
applied to the user's avatar. The system may have to validate any animations added to,
rewritten, or generated. For example, if the user performs an animation that is obscene,
the animation may be invalidated and not entered into the history data or not used to
rewrite an animation. Alternately, the avatar library may be a combination of animations
recorded by the user and/or pre-packaged animations.
[0154] At 807, the system may correlate the user's behaviors with particular
circumstances. For example, a user may behave in a certain maimer when the user
44
achieves success in a game application or when the user is idle in an experience while
watching an active user play the game. Data related to the user's behaviors, including the
correlation of the user's behaviors with any particular circumstances, may be stored such
as in an avatar library at 806. As described above, the avatar library may comprise prepackaged
animations or the avatar library may be associated wdth a particular user having
animations tailored to that user. User specific information may also include tendencies in
modes of play by one or more users. For example, if a user tends to behave or react in a
certain maimer, the system may track the user's tendencies to more accurately reflect the
user's behaviors under certain circumstances. Thus, the system can begin to track the
user's tendencies and use that information to more accurately reflect the user's behaviors.
[0155] At 806, the behaviors and animations corresponding to those behaviors,
associated with a user in the physical space, may be stored as part of a user profile. The
profile may be specific to a particular physical space or a user, for example, and may be
part of or include aspects of the avatar library. Avatar data, including features of the user,
may become part of the user's profile. A profile may be accessed upon entry of a user into
a capture scene. If a profile matches a user based on a password, selection by the user,
body size, voice recognition or the like, then the profile may be used in the determination
of the user's visual representation.
[0156] History data for a user may be monitored, storing information to the
user's profile. For example, the system may detect behavioral features specific to the user,
such as the user's behaviors, speech patterns, emotions, sounds, or the like. The system
may apply those features to the user's visual representation when applying a temperament
to the visual representation. For example, if the system identifies the user's behaviors and
selects an animation to comprising speech to reflect the behavior, the visual
representation's voice may be patterned from the user's speech patterns or may even be a
recording of the user's ovm voice.
[0157] The system may render an avatar associated with the user and, at 810,
apply an animation that is representative of the user's behaviors to the user's avatar. At
808, the system may identify contextual circumstances. Contextual circumstance may
comprise the condition of a user's physical environment, the condition of a user's virtual
environment, a status of a system, a status of an application, a success of the user in an
application, a failure of the user in an application, an active/non-active status of the user, a
presence of a second user, or a gesture, or the like. By comparing the contextual
circumstances to the history data, the system may identify any correlations between the
45
history data and contextual circumstance. If a correlation is identified, the system may
select an animation representative of the user's behavior that corresponds to the contextual
circumstance.
[0158] FIG. 9 shows a method for applying animations to a user's avatar. The
animations may be applied whether or not the user is present in the physical space. Thus,
the system may provide a reflection of the user, in the form of the avatar that has the
likeness of the user and behaves in accordance with the user. The user's avatar may
represent the user even if the user is not interacting with the application/system, such as if
the user is not present in the physical space. At 902, the system renders a visual
representation of the user. Based on information stored in the avatar library, such as that
described in FIG. 8, animations may be applied to the user's avatar that correspond to the
user.
[0159] The system may select animations, at 904, for application to the avatar
that correspond to the learned inputs of that particular user. If the user is not physically
present in the physical space, such as at 906, the animations may correspond to the user's
behavior learned by the system and stored in an avatar library associated with that user.
Thus, the avatar can appear to behave in a similar maimer to the user, even if the user is
not available in the physical space for capture by the capture device. A second user can
request that the system render a visual representation of the user that is not physically
present to simulate an experience with the first user.
[0160] If the user is present, such as at 908, the animations may be selected from
the avatar library or mapped directly to the user in the physical space as captured by the
system. The animation may be selected from an avatar library and may be representative
of a user's behavior identified fi-om a history of user data. Thus, the animations may be
selected based on the previous identity of behaviors captured by the system. Even if the
user is present in the physical space and data is captured by the capture device with respect
to the user, it may be desirable to apply an animation from the avatar library instead of
map the avatar directly to the user.
[0161] In an example embodiment, the animations applied to the avatar may be
animations selected from a library of pre-packaged animations, such as those that come
with a program, application, or a system, for example. The animations selected may be
those which correspond to the user's inputs learned by the system. In another example
embodiment, the animations in the library may be animations entered and recorded by the
user into the avatar's animation vocabulary. For example, the system or the user may
46
reprogram an animation to reflect the user's actual motions or behaviors, captured by a
capture device for example. Thus, animations may be added to or overwritten in the
library of avatar animations. Over time, the avatar in the virtual space may appear to
become a reflection of the user in the physical space, including the user's features,
behaviors, tendencies, voice patterns, etc.
[0162] It should be understood that the configurations and/or approaches
described herein are exemplary in nature, and that these specific embodiments or examples
are not to be considered limiting. The specific routines or methods described herein may
represent one or more of any number of processing strategies. As such, various acts
illustrated may be performed in the sequence illustrated, in other sequences, in parallel, or
the like. Likewise, the order of the above-described processes may be changed.
[0163] Furthermore, while the present disclosure has been described in
connection with the particular aspects, as illustrated in the various figures, it is understood
that other similar aspects may be used or modifications and additions may be made to the
described aspects for performing the same function of the present disclosure without
deviating there from. The subject matter of the present disclosure includes all novel and
non-obvious combinations and sub-combinations of the various processes, systems and
configurations, and other features, functions, acts, and/or properties disclosed herein, as
well as any and all equivalents thereof. Thus, the methods and apparatus of the disclosed
embodiments, or certain aspects or portions thereof, may take the form of program code
(i.e., instructions) embodied in tangible media, such as floppy diskettes, CD-ROMs, hard
drives, or any other machine-readable storage mediimi. When the program code is loaded
into and executed by a machine, such as a computer, the machine becomes an apparatus
configured for practicing the disclosed embodiments.
[0164] In addition to the specific implementations explicitly set forth herein,
other aspects and implementations will be apparent to those skilled in the art from
consideration of the specification disclosed herein. Therefore, the present disclosure
should not be limited to any single aspect, but rather construed in breadth and scope in
accordance with the appended claims. For example, the various procedures described
herein may be implemented with hardware or software, or a combination of both.

lAVe claim;
1. A method for applying an animation to a visual representation, the method
comprising:
rendering the visual representation of a user;
selecting an animation from an avatar library that is representative of a user's
behavior identified fi-om a history of user data, wherein the history of user data comprises
user data previously captured from a physical space; and
applying the animation fi"om the avatar library to the visual representation of the
user.
2. The method of claim 1, wherein the animation fi-om the avatar library is applied to
the visual representation when the user is not available in the physical space for capture by
the capture device.
3. The method of claim 2, wherein the unavailable user is a first user and the visual
representation of the first user is configured for rendering to a second user.
4. The method of claim 1, wherein the animation selected fi-om the avatar library and
applied to the user's visual representation does not correspond to data presently captured
by the capture device of the user present in the physical space.
5. The method of claim 1, fiirther comprising rewriting the animation in the avatar
library to correspond to the user's motion captvired by a capture device.
6. The method of claim 5, wherein rewriting the animation is prompted by a user's
gesture in the physical space.
7. A method for storing behavioral data captured by a capture device, the method
comprising:
receiving data of a physical space, wherein the data is representative of a user in
the physical space;
identifying characteristics indicative of a user's behavior from the data; and
storing a history of the characteristics indicative of the user's behavior.
8. The method of claim 7, fiirther comprising applying an animation to an avatar
associated with the user, wherein the animation is from an avatar library and is
representative of the user's behavior identified from the history data.
9. The method of claim 7, fiirther comprising correlating the user's behavior with a
contextual circumstance by correlating at least one of the characteristics indicative of the
user's behavior with the contextual circumstance.
48
10. The method of claim 7, wherein a contextual circumstance comprises at least one
of a condition of a user's physical environment, a condition of a user's virtual
environment, a status of a system, a status of an application, a success of the user in an
application, a failure of the user in an application, an active/non-active status of the user, a
presence of a second user, or a gesture.
11. The method of claim 10, further comprising:
identifying a contextual circumstance;
comparing the contextual circumstance to the history of the characteristics
indicative of the user's behavior and identifying a correlation between at least one of the
characteristics indicative of the user's behavior with the contextual circumstance; and
selecting, from an animation library, an animation representative of the user's
behavior that corresponds to the contextual circumstance.
12. The method of claim 7, further comprising at least one of adding to or rewriting an
animation to the avatar library,
wherein the avatar library is a pre-packaged avatar library, and rewriting an
animation comprises rewriting an animation in the pre-packaged avatar library to
correspond to the history of the characteristics indicative of the user's behavior, and
wherein adding the animation to the avatar library comprises recording a user's
motion in the physical space and adding an animation representative of the user's motion
to the avatar library.
13. The method of claim 12, further comprising validating the animation prior to
adding the animation to the avatar library.
14. The method of claim 7, wherein the characteristics indicative of the user's behavior
comprises at least one of physical characteristics, facial features, speech patterns,
vocabulary, voice commands, a gesture, motion, or body position.
15. The method of claim 7, wherein identifying characteristics of a user's behavior
from the data comprises passively identifying characteristics associated with natural
activity of the user or actively identifying characteristics associated with a user's gesture.
Dated this 09 January, 2012