PATENT DOCUMENT

Publication Number: US-11715220-B1
Application Number: US-202117379718-A
Country: US
Kind Code: B1

Title: Method and device for depth sensor power savings

Abstract:
In one implementation, a method of activating a depth sensor is performed by a device including a depth sensor including a plurality of depth sensor elements, a display, one or more processors, and non-transitory memory. The method includes obtaining content to be displayed on the display in association with a physical environment. The method includes selecting a subset of the plurality of depth sensor elements. The method includes activating the subset of the plurality of depth sensor elements to obtain a depth map of the physical environment. The method includes displaying, on the display, at least a portion of the content based on the depth map of the physical environment.

Claims:
What is claimed is: 
     
       1. A method comprising:
 at a device including a depth sensor including a plurality of depth sensor elements, a display having a plurality of display locations, one or more processors, and non-transitory memory: 
 obtaining content to be displayed on the display in association with a physical environment; 
 selecting a subset of the plurality of depth sensor elements corresponding to a subset of the plurality of display locations; 
 activating the subset of the plurality of depth sensor elements corresponding to the subset of the plurality of display locations without activating others of the plurality of depth sensor elements to obtain a depth map of the physical environment; and 
 displaying, on the display, at least a portion of the content based on the depth map of the physical environment. 
 
     
     
       2. The method of  claim 1 , wherein selecting the subset of the plurality of depth sensor elements is based on the content. 
     
     
       3. The method of  claim 2 , wherein the content is to be displayed over an area of the display, wherein each of the plurality of depth sensor elements corresponds to a respective one of the plurality of display locations, and wherein a depth sensor element of the plurality of depth sensor elements is more likely to be selected if the corresponding respective one of the plurality of display locations is within the area. 
     
     
       4. The method of  claim 1 , wherein selecting the subset of the plurality of depth sensor elements is based on a gaze of a user. 
     
     
       5. The method of  claim 4 , wherein the gaze of the user corresponds to a gaze location on the display, wherein each of the plurality of depth sensor elements corresponds to a respective one of the plurality of display locations, and wherein a depth sensor element of the plurality of depth sensor elements is more likely to be selected if the corresponding respective one of the plurality of display locations is within a threshold distance of the gaze location. 
     
     
       6. The method of  claim 1 , wherein selecting the subset of the plurality of depth sensor elements is based on a body pose of a user. 
     
     
       7. The method of  claim 6 , wherein selecting the subset of the plurality of depth sensor elements is based on a hand position of the user. 
     
     
       8. The method of  claim 7 , wherein the hand position of the user corresponds to a hand area of the display, wherein each of the plurality of depth sensor elements corresponds to a respective one of the plurality of display locations, and wherein a depth sensor element of the plurality of depth sensor elements is more likely to be selected if the corresponding respective one of the plurality of display locations is within the hand area of the display. 
     
     
       9. The method of  claim 1 , wherein selecting the subset of the plurality of depth sensor elements is based on a stored depth map of the physical environment stored in the non-transitory memory. 
     
     
       10. The method of  claim 9 , wherein selecting the subset of the plurality of depth sensor elements is based on pixel locations of depth elements of the stored depth map. 
     
     
       11. The method of  claim 9 , wherein selecting the subset of the plurality of depth sensor elements is based on pixel times of elements of the stored depth map. 
     
     
       12. The method of  claim 1 , wherein selecting the subset of the plurality of depth sensor elements is based on a dynamism of the physical environment. 
     
     
       13. The method of  claim 1 , wherein selecting the subset of the plurality of depth sensor elements is based on an amount of available power. 
     
     
       14. The method of  claim 1 , wherein the depth map of the physical environment is based on the output of the subset of the plurality of depth sensor elements without being based on others of the plurality of depth sensor elements. 
     
     
       15. A device comprising:
 a depth sensor including a plurality of depth sensor elements; 
 a display having a plurality of display locations; 
 a non-transitory memory; and 
 one or more processors to:
 obtain content to be displayed on the display in association with a physical environment; 
 select a subset of the plurality of depth sensor elements corresponding to a subset of the plurality of display locations; 
 activate the subset of the plurality of depth sensor elements corresponding to the subset of the plurality of display locations without activating others of the plurality of depth sensor elements to obtain a depth map of the physical environment; and 
 display, on the display, at least a portion of the content based on the depth map of the physical environment. 
 
 
     
     
       16. The device of  claim 15 , wherein the one or more processors select the subset of the plurality of depth sensor elements based on the content. 
     
     
       17. The device of  claim 15 , wherein the one or more processors select the subset of the plurality of depth sensor elements based on a gaze of a user. 
     
     
       18. The device of  claim 15 , wherein the one or more processors select the subset of the plurality of depth sensor elements based on an amount of available power. 
     
     
       19. A non-transitory computer-readable medium having instructions encoded thereon which, when executed by one or more processors of a device including a depth sensor including a plurality of depth sensor elements and a display having a plurality of display locations, cause the device to:
 obtain content to be displayed on the display in association with a physical environment; 
 select a subset of the plurality of depth sensor elements corresponding to a subset of the plurality of display locations; 
 activate the subset of the plurality of depth sensor elements corresponding to the subset of the plurality of display locations without activating others of the plurality of depth sensor elements to obtain a depth map of the physical environment; and 
 display, on the display, at least a portion of the content based on the depth map of the physical environment.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent App. No. 63/058,933, filed on Jul. 30, 2020, which is hereby incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure generally relates to systems, methods, and devices for reducing the amount of power consumed by a depth sensor. 
     BACKGROUND 
     In various implementations, a virtual object in an extended reality (XR) environment is, from at least a particular perspective, located behind an opaque object. Accordingly, at least a portion of the virtual object should not be displayed in an image of the XR environment (e.g., it is hidden by the opaque object). In various implementations, to accurately determine the boundaries of the portion of the virtual object that should not be displayed, a depth sensor is used. However, in various implementations, a depth sensor consumes a large amount of power. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the present disclosure can be understood by those of ordinary skill in the art, a more detailed description may be had by reference to aspects of some illustrative implementations, some of which are shown in the accompanying drawings. 
         FIG.  1    is a block diagram of an example operating environment in accordance with some implementations. 
         FIG.  2    is a block diagram of an example controller in accordance with some implementations. 
         FIG.  3    is a block diagram of an example electronic device in accordance with some implementations. 
         FIGS.  4 A- 4 D  illustrate the electronic device of  FIG.  3    displaying images of an XR environment in accordance with some implementations. 
         FIG.  5 A  illustrates an image of the physical environment upon which the XR environment of  FIGS.  4 A- 4 D  is based. 
         FIG.  5 B  illustrates the image of the physical environment of  FIG.  5 A  with a representation of a sparse depth map overlaid thereon. 
         FIG.  5 C  illustrates a first dense depth map for the image of the physical environment of  FIG.  5 A . 
         FIG.  5 D  illustrates an image of a virtual ball rendered at the same location as in  FIGS.  4 B- 4 D . 
         FIG.  5 E  illustrates a second dense depth map for the virtual ball of  FIG.  5 D . 
         FIG.  5 F  illustrates an occlusion map based on the first dense depth map of  FIG.  5 D  and the second dense depth map of  FIG.  5 F . 
         FIG.  5 G  illustrates an occluded image of the virtual ball based on the image of the virtual ball of  FIG.  5 D  and the occlusion map of  FIG.  5 F . 
         FIG.  5 H  illustrates a composite image based on the occluded image of the virtual ball of  FIG.  5 G  and the image of the physical environment of  FIG.  5 A . 
         FIGS.  6 A- 6 C  illustrate the image of the physical environment of  FIG.  5 A  with various representations of different sparse depth maps overlaid thereon. 
         FIG.  7    is a flowchart representation of a method of activating a depth sensor in accordance with some implementations. 
     
    
    
     In accordance with common practice the various features illustrated in the drawings may not be drawn to scale. Accordingly, the dimensions of the various features may be arbitrarily expanded or reduced for clarity. In addition, some of the drawings may not depict all of the components of a given system, method or device. Finally, like reference numerals may be used to denote like features throughout the specification and figures. 
     SUMMARY 
     Various implementations disclosed herein include devices, systems, and methods for activating a depth sensor. In various implementations, the method is performed by a device including a depth sensor including a plurality of depth sensor elements, a display, one or more processors, and non-transitory memory. The method includes obtaining content to be displayed on the display in association with a physical environment. The method includes selecting a subset of the plurality of depth sensor elements. The method includes activating the subset of the plurality of depth sensor elements to obtain a depth map of the physical environment. The method includes displaying, on the display, at least a portion of the content based on the depth map of the physical environment. 
     In accordance with some implementations, a device includes one or more processors, a non-transitory memory, and one or more programs; the one or more programs are stored in the non-transitory memory and configured to be executed by the one or more processors. The one or more programs include instructions for performing or causing performance of any of the methods described herein. In accordance with some implementations, a non-transitory computer readable storage medium has stored therein instructions, which, when executed by one or more processors of a device, cause the device to perform or cause performance of any of the methods described herein. In accordance with some implementations, a device includes: one or more processors, a non-transitory memory, and means for performing or causing performance of any of the methods described herein. 
     DESCRIPTION 
     Numerous details are described in order to provide a thorough understanding of the example implementations shown in the drawings. However, the drawings merely show some example aspects of the present disclosure and are therefore not to be considered limiting. Those of ordinary skill in the art will appreciate that other effective aspects and/or variants do not include all of the specific details described herein. Moreover, well-known systems, methods, components, devices, and circuits have not been described in exhaustive detail so as not to obscure more pertinent aspects of the example implementations described herein. 
     As noted above, in various implementations, at least a portion of a virtual object should not be displayed in an XR environment based on a physical environment (e.g., it is behind, hidden by, or occluded by an opaque object, which may be a physical object in the physical environment). In various implementations, to accurately determine the area of the portion of the virtual object that should not be displayed, a depth sensor is used to generate a depth map of the physical environment. However, in various implementations, a depth sensor consumes a large amount of power. In various implementations, the depth sensor includes a plurality of depth sensor elements. To reduce the amount of power used by the depth sensor, only a subset of the plurality of depth sensor elements are selected and activated to generate the depth map. 
       FIG.  1    is a block diagram of an example operating environment  100  in accordance with some implementations. While pertinent features are shown, those of ordinary skill in the art will appreciate from the present disclosure that various other features have not been illustrated for the sake of brevity and so as not to obscure more pertinent aspects of the example implementations disclosed herein. To that end, as a non-limiting example, the operating environment  100  includes a controller  110  and an electronic device  120 . 
     In some implementations, the controller  110  is configured to manage and coordinate an XR experience for the user. In some implementations, the controller  110  includes a suitable combination of software, firmware, and/or hardware. The controller  110  is described in greater detail below with respect to  FIG.  2   . In some implementations, the controller  110  is a computing device that is local or remote relative to the physical environment  105 . For example, the controller  110  is a local server located within the physical environment  105 . In another example, the controller  110  is a remote server located outside of the physical environment  105  (e.g., a cloud server, central server, etc.). In some implementations, the controller  110  is communicatively coupled with the electronic device  120  via one or more wired or wireless communication channels  144  (e.g., BLUETOOTH, IEEE 802.11x, IEEE 802.16x, IEEE 802.3x, etc.). In another example, the controller  110  is included within the enclosure of the electronic device  120 . In some implementations, the functionalities of the controller  110  are provided by and/or combined with the electronic device  120 . 
     In some implementations, the electronic device  120  is configured to provide the XR experience to the user. In some implementations, the electronic device  120  includes a suitable combination of software, firmware, and/or hardware. According to some implementations, the electronic device  120  presents, via a display  122 , XR content to the user while the user is physically present within the physical environment  105  that includes a table  107  within the field-of-view  111  of the electronic device  120 . As such, in some implementations, the user holds the electronic device  120  in his/her hand(s). In some implementations, while providing XR content, the electronic device  120  is configured to display a virtual object (e.g., a virtual cylinder  109 ) and to enable video pass-through of the physical environment  105  (e.g., including a representation  117  of the table  107 ) on a display  122 . The electronic device  120  is described in greater detail below with respect to  FIG.  3   . 
     According to some implementations, the electronic device  120  provides an XR experience to the user while the user is virtually and/or physically present within the physical environment  105 . 
     In some implementations, the user wears the electronic device  120  on his/her head. For example, in some implementations, the electronic device includes a head-mounted system (HMS), head-mounted device (HMD), or head-mounted enclosure (HME). As such, the electronic device  120  includes one or more XR displays provided to display the XR content. For example, in various implementations, the electronic device  120  encloses the field-of-view of the user. In some implementations, the electronic device  120  is a handheld device (such as a smartphone or tablet) configured to present XR content, and rather than wearing the electronic device  120 , the user holds the device with a display directed towards the field-of-view of the user and a camera directed towards the physical environment  105 . In some implementations, the handheld device can be placed within an enclosure that can be worn on the head of the user. In some implementations, the electronic device  120  is replaced with an XR chamber, enclosure, or room configured to present XR content in which the user does not wear or hold the electronic device  120 . 
       FIG.  2    is a block diagram of an example of the controller  110  in accordance with some implementations. While certain specific features are illustrated, those skilled in the art will appreciate from the present disclosure that various other features have not been illustrated for the sake of brevity, and so as not to obscure more pertinent aspects of the implementations disclosed herein. To that end, as a non-limiting example, in some implementations the controller  110  includes one or more processing units  202  (e.g., microprocessors, application-specific integrated-circuits (ASICs), field-programmable gate arrays (FPGAs), graphics processing units (GPUs), central processing units (CPUs), processing cores, and/or the like), one or more input/output (I/O) devices  206 , one or more communication interfaces  208  (e.g., universal serial bus (USB), FIREWIRE, THUNDERBOLT, IEEE 802.3x, IEEE 802.11x, IEEE 802.16x, global system for mobile communications (GSM), code division multiple access (CDMA), time division multiple access (TDMA), global positioning system (GPS), infrared (IR), BLUETOOTH, ZIGBEE, and/or the like type interface), one or more programming (e.g., I/O) interfaces  210 , a memory  220 , and one or more communication buses  204  for interconnecting these and various other components. 
     In some implementations, the one or more communication buses  204  include circuitry that interconnects and controls communications between system components. In some implementations, the one or more I/O devices  206  include at least one of a keyboard, a mouse, a touchpad, a joystick, one or more microphones, one or more speakers, one or more image sensors, one or more displays, and/or the like. 
     The memory  220  includes high-speed random-access memory, such as dynamic random-access memory (DRAM), static random-access memory (SRAM), double-data-rate random-access memory (DDR RAM), or other random-access solid-state memory devices. In some implementations, the memory  220  includes non-volatile memory, such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory  220  optionally includes one or more storage devices remotely located from the one or more processing units  202 . The memory  220  comprises a non-transitory computer readable storage medium. In some implementations, the memory  220  or the non-transitory computer readable storage medium of the memory  220  stores the following programs, modules and data structures, or a subset thereof including an optional operating system  230  and an XR experience module  240 . 
     The operating system  230  includes procedures for handling various basic system services and for performing hardware dependent tasks. In some implementations, the XR experience module  240  is configured to manage and coordinate one or more XR experiences for one or more users (e.g., a single XR experience for one or more users, or multiple XR experiences for respective groups of one or more users). To that end, in various implementations, the XR experience module  240  includes a data obtaining unit  242 , a tracking unit  244 , a coordination unit  246 , and a data transmitting unit  248 . 
     In some implementations, the data obtaining unit  242  is configured to obtain data (e.g., presentation data, interaction data, sensor data, location data, etc.) from at least the electronic device  120  of  FIG.  1   . To that end, in various implementations, the data obtaining unit  242  includes instructions and/or logic therefor, and heuristics and metadata therefor. 
     In some implementations, the tracking unit  244  is configured to map the physical environment  105  and to track the position/location of at least the electronic device  120  with respect to the physical environment  105  of  FIG.  1   . To that end, in various implementations, the tracking unit  244  includes instructions and/or logic therefor, and heuristics and metadata therefor. 
     In some implementations, the coordination unit  246  is configured to manage and coordinate the XR experience presented to the user by the electronic device  120 . To that end, in various implementations, the coordination unit  246  includes instructions and/or logic therefor, and heuristics and metadata therefor. 
     In some implementations, the data transmitting unit  248  is configured to transmit data (e.g., presentation data, location data, etc.) to at least the electronic device  120 . To that end, in various implementations, the data transmitting unit  248  includes instructions and/or logic therefor, and heuristics and metadata therefor. 
     Although the data obtaining unit  242 , the tracking unit  244 , the coordination unit  246 , and the data transmitting unit  248  are shown as residing on a single device (e.g., the controller  110 ), it should be understood that in other implementations, any combination of the data obtaining unit  242 , the tracking unit  244 , the coordination unit  246 , and the data transmitting unit  248  may be located in separate computing devices. 
     Moreover,  FIG.  2    is intended more as functional description of the various features that may be present in a particular implementation as opposed to a structural schematic of the implementations described herein. As recognized by those of ordinary skill in the art, items shown separately could be combined and some items could be separated. For example, some functional modules shown separately in  FIG.  2    could be implemented in a single module and the various functions of single functional blocks could be implemented by one or more functional blocks in various implementations. The actual number of modules and the division of particular functions and how features are allocated among them will vary from one implementation to another and, in some implementations, depends in part on the particular combination of hardware, software, and/or firmware chosen for a particular implementation. 
       FIG.  3    is a block diagram of an example of the electronic device  120  in accordance with some implementations. While certain specific features are illustrated, those skilled in the art will appreciate from the present disclosure that various other features have not been illustrated for the sake of brevity, and so as not to obscure more pertinent aspects of the implementations disclosed herein. To that end, as a non-limiting example, in some implementations the electronic device  120  includes one or more processing units  302  (e.g., microprocessors, ASICs, FPGAs, GPUs, CPUs, processing cores, and/or the like), one or more input/output (I/O) devices and sensors  306 , one or more communication interfaces  308  (e.g., USB, FIREWIRE, THUNDERBOLT, IEEE 802.3x, IEEE 802.11x, IEEE 802.16x, GSM, CDMA, TDMA, GPS, IR, BLUETOOTH, ZIGBEE, and/or the like type interface), one or more programming (e.g., I/O) interfaces  310 , one or more XR displays  312 , one or more optional interior- and/or exterior-facing image sensors  314 , a memory  320 , and one or more communication buses  304  for interconnecting these and various other components. 
     In some implementations, the one or more communication buses  304  include circuitry that interconnects and controls communications between system components. In some implementations, the one or more I/O devices and sensors  306  include at least one of an inertial measurement unit (IMU), an accelerometer, a gyroscope, a thermometer, one or more physiological sensors (e.g., blood pressure monitor, heart rate monitor, blood oxygen sensor, blood glucose sensor, etc.), one or more microphones, one or more speakers, a haptics engine, a depth sensor  307  including a plurality of depth sensor elements (e.g., a structured light, a time-of-flight, or the like), and/or the like. 
     In some implementations, the one or more XR displays  312  are configured to provide the XR experience to the user. In some implementations, the one or more XR displays  312  correspond to holographic, digital light processing (DLP), liquid-crystal display (LCD), liquid-crystal on silicon (LCoS), organic light-emitting field-effect transitory (OLET), organic light-emitting diode (OLED), surface-conduction electron-emitter display (SED), field-emission display (FED), quantum-dot light-emitting diode (QD-LED), micro-electro-mechanical system (MEMS), and/or the like display types. In some implementations, the one or more XR displays  312  correspond to diffractive, reflective, polarized, holographic, etc. waveguide displays. For example, the electronic device  120  includes a single XR display. In another example, the electronic device includes an XR display for each eye of the user. In some implementations, the one or more XR displays  312  are capable of presenting MR and VR content. 
     In some implementations, the one or more image sensors  314  are configured to obtain image data that corresponds to at least a portion of the face of the user that includes the eyes of the user (any may be referred to as an eye-tracking camera). In some implementations, the one or more image sensors  314  are configured to be forward-facing so as to obtain image data that corresponds to the environment as would be viewed by the user if the electronic device  120  was not present (and may be referred to as a scene camera). The one or more optional image sensors  314  can include one or more RGB cameras (e.g., with a complimentary metal-oxide-semiconductor (CMOS) image sensor or a charge-coupled device (CCD) image sensor), one or more infrared (IR) cameras, one or more event-based cameras, and/or the like. 
     The memory  320  includes high-speed random-access memory, such as DRAM, SRAM, DDR RAM, or other random-access solid-state memory devices. In some implementations, the memory  320  includes non-volatile memory, such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. The memory  320  optionally includes one or more storage devices remotely located from the one or more processing units  302 . The memory  320  comprises a non-transitory computer readable storage medium. In some implementations, the memory  320  or the non-transitory computer readable storage medium of the memory  320  stores the following programs, modules and data structures, or a subset thereof including an optional operating system  330  and an XR presentation module  340 . 
     The operating system  330  includes procedures for handling various basic system services and for performing hardware dependent tasks. In some implementations, the XR presentation module  340  is configured to present XR content to the user via the one or more XR displays  312 . To that end, in various implementations, the XR presentation module  340  includes a data obtaining unit  342 , a depth sensor selection unit  344 , an XR presenting unit  346 , and a data transmitting unit  348 . 
     In some implementations, the data obtaining unit  342  is configured to obtain data (e.g., presentation data, interaction data, sensor data, location data, etc.) from at least the controller  110  of  FIG.  1   . To that end, in various implementations, the data obtaining unit  342  includes instructions and/or logic therefor, and heuristics and metadata therefor. 
     In some implementations, the depth sensor selection unit  344  is configured to select a subset of the plurality of depth sensor elements of the depth sensor  307  and activate the subset of the plurality of depth sensor elements to generate a depth map of physical environment. To that end, in various implementations, the depth sensor selection unit  344  includes instructions and/or logic therefor, and heuristics and metadata therefor. 
     In some implementations, the XR presenting unit  346  is configured to display, via the one or more XR displays  312 , at least portion of a virtual object based on the depth map of the physical environment. To that end, in various implementations, the XR presenting unit  346  includes instructions and/or logic therefor, and heuristics and metadata therefor. 
     In some implementations, the data transmitting unit  348  is configured to transmit data (e.g., presentation data, location data, etc.) to at least the controller  110 . In some implementations, the data transmitting unit  348  is configured to transmit authentication credentials to the electronic device. To that end, in various implementations, the data transmitting unit  348  includes instructions and/or logic therefor, and heuristics and metadata therefor. 
     Although the data obtaining unit  342 , the depth sensor selection unit  344 , the XR presenting unit  346 , and the data transmitting unit  348  are shown as residing on a single device (e.g., the electronic device  120 ), it should be understood that in other implementations, any combination of the data obtaining unit  342 , the depth sensor selection unit  344 , the XR presenting unit  346 , and the data transmitting unit  348  may be located in separate computing devices. 
     Moreover,  FIG.  3    is intended more as a functional description of the various features that could be present in a particular implementation as opposed to a structural schematic of the implementations described herein. As recognized by those of ordinary skill in the art, items shown separately could be combined and some items could be separated. For example, some functional modules shown separately in  FIG.  3    could be implemented in a single module and the various functions of single functional blocks could be implemented by one or more functional blocks in various implementations. The actual number of modules and the division of particular functions and how features are allocated among them will vary from one implementation to another and, in some implementations, depends in part on the particular combination of hardware, software, and/or firmware chosen for a particular implementation. 
       FIG.  4 A  illustrates the electronic device  120  of  FIG.  1    displaying a first image of an XR environment  401 . The first image of the XR environment  401  represents the XR environment at a first time. The XR environment is based on a physical environment including a chair in a room having a floor. Accordingly, the first image of the XR environment  401  includes a representation of the chair  410  and a representation of the floor  412 . 
     The XR environment further includes a virtual ball on the floor. Accordingly, the first image of the XR environment  401  includes a representation of the virtual ball  420  on the representation of the floor  412 . 
       FIG.  4 B  illustrates the electronic device  120  of  FIG.  1    displaying a second image of the XR environment  402 . The second image of the XR environment  402  represents the XR environment at a second time in which, as compared to the first time, the virtual ball has moved to a location in which a portion of the virtual ball is, at least from the perspective of the second image of the XR environment  402 , behind the chair. 
     Accordingly, a portion of the virtual ball  420  is not displayed. In the second image of the XR environment  402 , the portion of the virtual ball that is not displayed is underestimated, resulting in under-occlusion in which a portion of the virtual ball  426  is visible through the representation of the chair  410 . 
       FIG.  4 C  illustrates the electronic device  120  of  FIG.  1    displaying a third image of the XR environment  403 . The third image of the XR environment  403  represents the XR environment at the second time in which, as compared to the first time, the virtual ball has moved to a location in which a portion of the virtual ball is, at least from the perspective of the third image of the XR environment  403 , behind the chair. 
     Accordingly, a portion of the virtual ball is not displayed as part of the representation of the virtual ball  420 . In the third image of the XR environment  403 , the portion of the virtual ball that is not displayed is overestimated, resulting in over-occlusion in which a gap  427  is displayed between the representation of the virtual ball  420  and the representation of the chair  410 . 
       FIG.  4 D  illustrates the electronic device  120  of  FIG.  1    displaying a fourth image of the XR environment  404 . The fourth image of the XR environment  404  represents the XR environment at the second time in which, as compared to the first time, the virtual ball has moved to a location in which a portion of the virtual ball is, at least from the perspective of the fourth image of the XR environment  404 , behind the chair. 
     Accordingly, a portion of the virtual ball is not displayed as part of the representation of the virtual ball  420 . In the fourth image of the XR environment  404 , the portion of the virtual ball that is not displayed is correctly estimated, resulting in realistic occlusion in which no portion of the representation of the virtual ball  420  is visible through the representation of the chair  410  and there is no gap between the representation of the virtual ball  420  and the representation of the chair  410 . 
       FIG.  5 A  illustrates an image of the physical environment  501  upon which the XR environment of  FIGS.  4 A- 4 D  is based. The image of the physical environment  501  includes the representation of the chair  410  and the representation of the floor  412 . 
     In various implementations, the image of the physical environment  501  includes an m×n matrix of pixels. Each pixel is associated with a respective pixel location defined by a respective row and respective column of the matrix. Each pixel is further associated with a respective pixel value. In various implementations, the pixel value is a single value, e.g., ranging from 0 to 255. In various implementations, the pixel value is an RGB triplet including a red value, green value, and blue value. 
       FIG.  5 B  illustrates the image of the physical environment  501  of  FIG.  5 A  with a representation of a sparse depth map  530  overlaid thereon. The sparse depth map includes a plurality of depth elements (represented by black circles in  FIG.  5 B ), each associated with a respective pixel location of the image of the physical environment  501  and a respective depth. The sparse depth map includes a depth for a number (but not all) of the pixels of the image of the physical environment  501 . In various implementations, the sparse depth map is generated by using a depth sensor, such as a 3D scanner or LIDAR scanner. In various implementations, the depth sensor includes a plurality of depth sensor elements and each of the depth elements corresponds to a respective depth sensor element. 
       FIG.  5 C  illustrates a first dense depth map  502  for the image of the physical environment  501  of  FIG.  5 A . The first dense depth map  502  includes a depth for each pixel of the image of the physical environment  501 .  FIG.  5 C  illustrates the depth for each pixel of the image of the physical environment  501  in grayscale, where lighter colors correspond to greater depths. Accordingly, the region of the first dense depth map corresponding to the floor  512  is lighter than the region of the first dense depth map corresponding to the chair  510 . Further, the region of the first dense depth map corresponding to floor  512  trends lighter further from the camera (or depth sensor) towards the wall. Further, various regions of the first dense depth map  502  corresponding to different portions of the chair are different intensities, with the back of the chair being darkest, the left arm of the chair being lighter, and the seat of the chair being lightest (but still darker than the region of the first dense depth map corresponding to the floor  512 ). 
     In various implementations, the first dense depth map  502  is generated from the sparse depth map using interpolation or other techniques. In various implementations, the first dense depth map  502  is generated from the sparse depth map using the image of the physical environment  501  or a mesh model of the physical environment as guidance. 
     Notably, due to the low resolution of the sparse depth map (of which the representation of the sparse depth map  530  is shown in  FIG.  5 B ), the edges of the region of the first dense depth map corresponding to the chair  510  poorly correspond to the edges of the region occupied by the representation of the chair  410  in the image of the physical environment  501 . 
       FIG.  5 D  illustrates an image of a virtual ball  503  rendered at the same location as in  FIGS.  4 B- 4 D . In various implementations, the image of the virtual ball  503  includes an m×n matrix of pixels. Each pixel is associated with a respective pixel location defined by a respective row and respective column of the matrix. Each pixel is further associated with a respective pixel value. In various implementations, the pixel value is a single value, e.g., ranging from 0 to 255. In various implementations, the pixel value is an RGB triplet including a red value, green value, and blue value. In various implementations, the pixel value is an RGBA set including a red value, green value, blue value, and transparency value. In various implementations, pixels corresponding to regions without content include a transparency value indicating complete transparency (e.g., an alpha value of 0). 
       FIG.  5 E  illustrates a second dense depth map  504  for the virtual ball. The second dense depth map  504  includes a depth value for each pixel of the image of the virtual ball  503  including content. In various implementations, the second depth map  504  includes a placeholder value (e.g., 0, NaN, or infinity) for pixels of the image not including content.  FIG.  5 E  illustrates the depth for each pixel of the image of the virtual ball  503  in grayscale, where lighter colors correspond to greater depths. Accordingly, the region of the second dense depth map  504  corresponding to the virtual ball  520  is darker than the remainder of the second dense depth map  504  (but not as dark as the region of the first dense depth map  502  corresponding to the chair  510 ). 
       FIG.  5 F  illustrates an occlusion map  505  based on the first dense depth map  502  of  FIG.  5 C  and the second dense depth map  504  of  FIG.  5 E . In various implementations, the occlusion map  505  includes an m×n matrix of pixels. Each pixel is associated with a respective pixel location defined by a respective row and respective column of the matrix. Each pixel is further associated with a respective pixel value. In various implementations, the pixel value is either 0 or 1. In various implementations, the pixel value ranges from 0 to 1. 
     The occlusion map  505  includes an occlusion region  541  estimating pixel locations at which the virtual ball is occluded by objects in the physical environment. 
     In various implementations, each pixel of the occlusion map  505  is set to a value of 0 if the pixel value (corresponding to depth, not closeness) of the corresponding pixel of the second dense depth map  504  is less than the pixel value of the corresponding pixel of the first dense depth map  502 ; otherwise, the pixel value is set to a value of 1. Alternatively, each pixel of the occlusion map  505  is set to a value of 0 if the pixel value (corresponding to closeness, not depth) of the corresponding pixel of the second dense depth map  504  is greater than the pixel value of the corresponding pixel of the first dense depth map  502 ; otherwise, the pixel value is set to a value of 1. 
     In various implementations, each pixel of the occlusion map  505  is set to a value of 0 if the pixel value (corresponding to depth, not closeness) of the corresponding pixel of the second dense depth map  504  is the placeholder value or less than the pixel value of the corresponding pixel of the first dense depth map  502 ; otherwise, the pixel value is set to a value of 1. Alternatively, each pixel of the occlusion map  505  is set to a value of 0 if the pixel value (corresponding to closeness, not depth) of the corresponding pixel of the second dense depth map  504  is the placeholder value or greater than the pixel value of the corresponding pixel of the first dense depth map  502 ; otherwise, the pixel value is set to a value of 1. 
       FIG.  5 G  illustrates an occluded image of the virtual ball  506  based on the image of the virtual ball  503  of  FIG.  5 D  and the occlusion map  505  of  FIG.  5 F . In various implementations, the occluded image of the virtual ball  506  includes an m×n matrix of pixels. Each pixel is associated with a respective pixel location defined by a respective row and respective column of the matrix. Each pixel is further associated with a respective pixel value. In various implementations, the pixel value is a single value, e.g., ranging from 0 to 255. In various implementations, the pixel value is an RGB triplet including a red value, green value, and blue value. In various implementations, the pixel value is an RGBA set including a red value, green value, blue value, and transparency value (or alpha value). In various implementations, pixels corresponding to regions without content include a transparency value indicating complete transparency (e.g., an alpha value of 0). 
     The occluded image of the virtual ball  506  includes an occluded representation of the virtual ball  421 . The occluded image of the virtual ball  506  differs from image of the virtual ball  503  in that the occluded representation of the virtual ball  421  does not include a portion occluded by objects in the physical environment. 
     In various implementations, the occluded image of the virtual ball  506  is generated by modifying the transparency value of each pixel at a respective pixel location based on the pixel value of the corresponding pixel of the occlusion map  505 . In various implementations, the transparency value is set to a value, wherein the value is 1 minus the pixel value of the corresponding pixel of the occlusion map  505 . In various implementations, the transparency value is multiplied by a factor, wherein the factor is 1 minus the pixel value of the corresponding pixel of the occlusion map  505 . 
       FIG.  5 H  illustrates a composite image  507  based on the occluded image of the virtual ball  506  of  FIG.  5 G  and the image of the physical environment  501  of  FIG.  5 A . In various implementations, the composite image  507  is a composite of the occluded image of the virtual ball  506  and the image of the physical environment  501 . In various implementations, the composite image  507  includes an m×n matrix of pixels. Each pixel is associated with a respective pixel location defined by a respective row and respective column of the matrix. Each pixel is further associated with a respective pixel value. In various implementations, the pixel value is a single value, e.g., ranging from 0 to 255. In various implementations, the pixel value is an RGB triplet including a red value, green value, and blue value. 
     In various implementations, the pixel value of a pixel of the composite image at a respective location (C c ) is a weighted average of the RGB value (or grayscale value) of the corresponding pixel of the occluded image of the virtual ball  506  (C o ) and the corresponding pixel value of the image of the physical environment  501  (C p ), weighted by the transparency value of the corresponding pixel of the occluded image of the virtual ball  506  (α), e.g. C c =αC o +(1−α)C p . 
     Notably, due to the poor correspondence between the edges of the region of the first dense depth map corresponding to the chair  510  (illustrated in  FIG.  5 C ) and the edges of the region occupied by the representation of the chair  410  in the image of the physical environment  501  (illustrated in  FIG.  5 A ) caused by the low resolution of the sparse depth map, the virtual ball is over-occluded, resulting in a gap  527  in  FIG.  5 H . 
     Increasing the resolution of the sparse depth map increases the correspondence between edges of the first dense depth map  502  and the image of the physical environment  501  and, therefore, decreases under-occlusion and over-occlusion. However, increasing the number of depth sensor elements of a depth sensor increases the cost of the depth sensor. Further, using a larger number of depth sensor elements of a depth sensor increases the power consumed by the depth sensor. 
     As noted above, in various implementations, a sparse depth map is generated by using a depth sensor including a plurality of depth sensor elements. Each depth sensor element generates a depth element of the sparse depth map for a respective location of the image of the physical environment  501 . 
     In various implementations, the depth sensor is adjusted to change the respective locations of the image of the physical environment  501  prior to activation of the depth sensor elements to generate the sparse depth map. For example, in various implementations, a varifocal lens of the depth sensor is adjusted to bring the respective locations closer together or further apart. As another example, in various implementations, at least a portion of the depth sensor (such as a lens) is tilted to move the respective locations up, down, left, or right. Thus, the depth sensor generates a higher density of depth elements at a relevant area of the image, such as the area in which a virtual object is to be displayed (e.g., where occlusion may occur), an area surrounding a gaze of a user (e.g., where under-occlusion or over-occlusion may be noticed), or the area of a hand of a user (e.g., where occlusion may occur or be noticed in the future). 
     In various implementations, a subset of the depth sensor elements is selected for activation to generate the sparse depth map. For example, in various implementations, the resolution of the sparse depth map is reduced (in various implementations, to zero), in non-relevant areas. Thus, the depth sensor consumes less power by not activating depth sensor elements corresponding to non-relevant areas of the image of the physical environment  501 . In various implementations, the depth sensor elements are partitioned into groups, each group including the depth sensor elements corresponding to tiles of the image of the physical environment  501 . For example, in various implementations, the depth sensor elements are partitioned into an upper-left group (corresponding to the upper-left quadrant of the image of the physical environment  501 ), an upper-right group (corresponding to the upper-right quadrant of the image of the physical environment  501 ), a lower-left group (corresponding to the lower-left quadrant of the image of the physical environment  501 ), and a lower-right group (corresponding to the lower-right quadrant of the image of the physical environment  501 ). In various implementations, selecting the subset of the depth sensor elements includes selecting groups of the depth sensor elements in relevant locations or areas. 
       FIG.  6 A  illustrates the image of the physical environment  501  of  FIG.  5 A  with a representation of a first sparse depth map  601  overlaid thereon. The first sparse depth map includes a plurality of depth elements in an area in which the virtual ball is to be displayed. In various implementations, the first sparse depth map is generated using a depth sensor adjusted to generate depth elements over the area in which the virtual ball is to be displayed. In various implementations, the first sparse depth map is generated by selecting depth sensor elements corresponding to locations in the area in which the virtual ball is to be displayed. 
       FIG.  6 B  illustrates the image of the physical environment  501  of  FIG.  5 A  with a representation of a second sparse depth map  602  overlaid thereon. The second sparse depth map includes a plurality of depth elements in the upper-right quadrant of the image of the physical environment  501  in which a gaze of the user is directed (as indicated by a gaze indicator  450  also overlaid on the image of the physical environment  501 ). In various implementations, the second sparse depth map is generated using a depth sensor adjusted to generate depth elements over the quadrant in which the gaze of the user is directed. In various implementations, the second sparse depth map is generated by selecting a group of depth sensor elements including the location to which the gaze of the user is directed. 
       FIG.  6 C  illustrates the image of the physical environment  501  of  FIG.  5 A  with a representation of a third sparse depth map  603  overlaid thereon. The third sparse depth map includes a plurality of depth elements having a higher concentration (or resolution) in the area in which the hand of user  690  is detected. In various implementations, the hand of the user  690  is detected in the image of the physical environment  501  using object recognition or gesture tracking techniques. In various implementations, the hand of the user  690  is detected using an inertial measurement unit (IMU) coupled to the hand of the user  690 . In various implementations, the third sparse depth map is generated using a depth sensor adjusted to generate depth elements having a higher concentration in the area in which the hand of the user  690  is detected. In various implementations, the third sparse depth map is generated by selecting a greater concentration of depth sensor elements corresponding to locations in the area in which the hand of the user  690  than depth sensor elements corresponding to locations outside the area in which the hand of the user  690  is detected. Thus, the percentage of depth sensor elements selected within the area is greater than the percentage of depth sensor elements selected outside of the area. 
     Any of the sparse depth maps (or properties thereof) can be used when selection is based on location of virtual objects, gaze, object recognition, or other heuristics. For example, when a virtual object is at a location, the second sparse depth map  602  (selecting a group of depth sensor elements corresponding to an area including the location without selecting other depth sensor elements) or the third sparse depth map  603  (selecting a greater percentage of depth sensor elements inside an area including the location than outside the area) can be used. As another example, when gaze is directed to a location, the first sparse depth map  601  (selecting depth sensor elements in an area surrounding the location without selecting other depth sensor elements) or the third sparse depth map  603  can be used. As another example, when a real object is at a location, the first sparse depth map  601  or the second sparse depth map  602  can be used. 
       FIG.  7    is a flowchart representation of a method  700  of activating a depth sensor in accordance with some implementations. In various implementations, the method  700  is performed by a device with a depth sensor including a plurality of depth sensor elements, a display, one or more processors, and non-transitory memory (e.g., the electronic device  120  of  FIG.  3   ). In some implementations, the method  700  is performed by processing logic, including hardware, firmware, software, or a combination thereof. In some implementations, the method  700  is performed by a processor executing instructions (e.g., code) stored in a non-transitory computer-readable medium (e.g., a memory). 
     The method  700  begins, in block  710 , with the device obtaining content to be displayed on the display in association with a physical environment. For example,  FIG.  5 D  illustrates an image of a virtual ball  503 . In various implementations, the display is an opaque display and the content is displayed in association with the physical environment as a composite image of at least a portion of the content and an image of the physical environment. For example,  FIG.  5 H  illustrates a composite image  507  including the occluded representation of the virtual ball  421  composited with the image of the physical environment  501  of  FIG.  5 A . In various implementations, the display is a transparent display and the virtual content is displayed in association with the physical environment as a projection over a view of the physical environment. 
     The method  700  continues, in block  720 , with the device selecting a subset of the plurality of depth sensor elements. In various implementations, selecting the subset of the plurality of depth sensor elements is based on the content. In various implementations, the content is to be displayed over an area of the display, each of the plurality of depth sensor elements corresponds to an element location on the display, and a depth sensor element of the plurality of depth sensor elements is more likely to be selected if the corresponding element location is within the area. For example,  FIG.  6 A  illustrates a sparse depth map generated by selecting depth sensor elements having corresponding element locations in an area in which the virtual ball is to be displayed. 
     In various implementations, selecting the subset of the plurality of depth sensor elements is based on a gaze of a user. In various implementations, the gaze of the user corresponds to a gaze location on the display, each of the plurality of depth sensor elements corresponds to an element location on the display, and a depth sensor element of the plurality of depth sensor elements is more likely to be selected if the corresponding element location is within a threshold distance of the gaze location. For example,  FIG.  6 B  illustrates a sparse depth map generated by selecting depth sensor elements having corresponding element locations in a quadrant of a gaze location of a gaze of the user. 
     In various implementations, selecting the subset of the plurality of depth sensor elements is based on a body pose of a user. In various implementations, selecting the subset of the plurality of depth sensor elements is based on a hand position of a user. In various implementations, the hand position of the user corresponds to a hand area of the display, wherein each of the plurality of depth sensor elements corresponds to an element location on the display, and wherein a depth sensor element of the plurality of depth sensor elements is more likely to be selected if the corresponding element location is within the hand area of the display. For example,  FIG.  6 C  illustrates a sparse depth map generated by preferentially selecting depth sensor elements having corresponding element locations in a hand area of the display. 
     In various implementations, selecting the subset of the plurality of depth sensor elements is based on a stored depth map of the scene stored in the non-transitory memory. In various implementations, selecting the subset of the plurality of depth sensor elements is based on pixel locations of depth elements of the stored depth map. For example, if the stored depth map includes depth elements for pixel locations on the right side of the display, depth sensor elements for element locations on the left side of the display are selected to generate a complete depth map. In various implementations, selecting the subset of the plurality of depth sensor elements is based on pixel times of elements of the stored depth map. For example, if the stored depth map includes a first set of depth elements for pixel locations on the right side of the display associated with a first capture time and a second set of depth elements for pixel locations on the left side of the display associated with a second capture time, depth sensor elements for element locations on side of the display least recently captured are selected. 
     In various implementations, selecting the subset of the plurality of depth sensor elements is based on a dynamism of the physical environment. For example, if the physical environment is more dynamic, more depth sensor elements are selected than if the physical environment is static. 
     In various implementations, selecting the subset of the plurality of depth sensor elements is based on an amount of available power. For example, if a battery level is low, fewer depth sensor elements are selected than if the battery level is high. 
     In various implementations, each of the plurality of depth sensor elements corresponds to an element location on the display. In various implementations, selecting the subset of the plurality of depth sensor elements includes selecting depth sensor elements with corresponding element locations within a contiguous area without selecting depth sensor elements with corresponding element locations outside of the contiguous area. In various implementations, selecting the subset of the plurality of depth sensor elements includes selecting a higher percentage of the depth sensor elements with corresponding element locations within a contiguous area than the percentage of depth sensor elements selected with corresponding element locations outside of the contiguous area. 
     The method  700  continues, in block  730 , with the device activating the subset of the plurality of depth sensor elements to obtain a depth map of the physical environment. For example,  FIG.  5 B  illustrates a representation of a sparse depth map  530  which may be generated with a depth sensor. As another example,  FIG.  5 C  illustrates a dense depth map  502  based on the sparse depth map  530  of  FIG.  5 B . 
     In various implementations, activating the subset of the plurality of depth sensor elements to obtain a depth map of the physical environment excludes activating others of the plurality of depth sensor elements. In various implementations, the depth map of the physical environment is based on the output of the subset of the plurality of depth sensor elements without being based on others of the plurality of depth sensor elements. 
     The method  700  continues, in block  740 , with the device displaying, on the display, at least a portion of the content based on the depth map of the physical environment. For example,  FIG.  5 H  illustrates a composite image  507  including the occluded representation of the virtual ball  421  composited with the image of the physical environment  501  of  FIG.  5 A . 
     Thus, in various implementations, power consumption by depth sensor elements of the depth sensor is balanced with the usefulness (or importance, worth, or significance) of the depth elements of the generated depth map. Accordingly, in various implementations, depth sensor elements are not activated (or, at least, few depth sensor elements are activated) to generate depth elements that are not used (e.g., to determine if occlusion is to occur), are not noticed (e.g., where the user is not looking), or redundant (e.g., previously determined and stored and unchanging). 
     While various aspects of implementations within the scope of the appended claims are described above, it should be apparent that the various features of implementations described above may be embodied in a wide variety of forms and that any specific structure and/or function described above is merely illustrative. Based on the present disclosure one skilled in the art should appreciate that an aspect described herein may be implemented independently of any other aspects and that two or more of these aspects may be combined in various ways. For example, an apparatus may be implemented and/or a method may be practiced using any number of the aspects set forth herein. In addition, such an apparatus may be implemented and/or such a method may be practiced using other structure and/or functionality in addition to or other than one or more of the aspects set forth herein. 
     It will also be understood that, although the terms “first,” “second,” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first node could be termed a second node, and, similarly, a second node could be termed a first node, which changing the meaning of the description, so long as all occurrences of the “first node” are renamed consistently and all occurrences of the “second node” are renamed consistently. The first node and the second node are both nodes, but they are not the same node. 
     The terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting of the claims. As used in the description of the implementations and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the term “and/or” as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. 
     As used herein, the term “if” may be construed to mean “when” or “upon” or “in response to determining” or “in accordance with a determination” or “in response to detecting,” that a stated condition precedent is true, depending on the context. Similarly, the phrase “if it is determined [that a stated condition precedent is true]” or “if [a stated condition precedent is true]” or “when [a stated condition precedent is true]” may be construed to mean “upon determining” or “in response to determining” or “in accordance with a determination” or “upon detecting” or “in response to detecting” that the stated condition precedent is true, depending on the context.

Metadata:
Filing Date: 20210719
Publication Date: 20230801
Grant Date: 20230801
Priority Date: 20200730
Inventors: SALTER, Thomas G.
CHIMALAMARRI, ANSHU KAMESWAR
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F3/011", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/013", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01S17/89", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06T7/50", "inventive": true, "first": true, "tree": "[]"}, {"code": "G01C3/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/013", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06T15/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06T19/006", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06T19/006", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06T15/40", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06T7/50", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06T19/006", "inventive": true, "first": false, "tree": "[]"}, {"code": "G01C3/08", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06T15/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/013", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 87472839