Dof control in XR experience

Abstract

Systems, methods, and tools are disclosed for degree of freedom (DoF) control in an augmented reality (XR) experience. In an example, a device may determine a first basic degree of freedom (DoF) boundary associated with a user. The first basic DoF boundary may be determined based on at least one of information prior to runtime or runtime information. The device may determine a second basic DoF boundary associated with the user based at least on information prior to the runtime or the runtime information. The device may determine a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary. Under the condition that the determination of the merged DoF boundary is successful, the device may determine to control movement of the user based on the merged boundary.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of European Provisional Patent Application No. 22305881.9 filed on June 17, 2022, the contents of which are incorporated herein by reference. Background Art

[0003] Video coding systems may be used to compress digital video signals, e.g., to reduce storage and / or transmission bandwidth required for such signals. Video coding systems may include, for example, wavelet-based systems, object-based systems, and / or block-based systems (such as block-based hybrid video coding systems). In extended reality (XR) applications, mechanisms for providing control of degree of freedom boundaries may be insufficient. Summary of the invention

[0004] Systems, methods, and tools for degree of freedom (DoF) control in an extended reality (XR) experience are disclosed. In an example, a device may determine a first basic degree of freedom (DoF) boundary associated with a user. The first basic DoF boundary may be determined based on at least one of pre-runtime information or runtime information. The device may determine a second basic DoF boundary associated with the user based at least on the pre-runtime information or the runtime information. The device may determine a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary. Conditional on the success of the determination of the merged DoF boundary, the device may determine to control movement of the user based on the merged boundary.

[0005] Under the condition that the determination of the merged DoF boundary is unsuccessful, the device may modify the first basic DoF boundary or the second basic DoF boundary to obtain a modified DoF boundary. The device may determine a new merged DoF boundary based on the modified DoF boundary and the first basic DoF boundary or the second basic DoF boundary. The device may determine the modified DoF boundary by determining a volume asset that does not take into account one or more of the first basic DoF boundary or the second basic DoF boundary. The device may determine the modified DoF boundary by modifying a spatial constraint associated with the first basic DoF boundary or the second basic DoF boundary. The device may modify the spatial constraint by prompting the user to modify the user's physical environment.

[0006] On the condition that the determination of the merged DoF boundary is unsuccessful, the device may modify a virtual item within the XR environment associated with the user. The device may determine the merged DoF boundary based on the first base DoF boundary and the second base DoF boundary by determining that a physical environment of the first base DoF boundary and a physical environment of the second base DoF boundary are different. Based on the difference, the device may determine that the first base DoF boundary is not allowed in the merged DoF boundary.

[0007] The device may determine a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary by determining that the physical environment of the first basic DoF boundary is different from the physical environment of the second basic DoF boundary. Based on the difference, the device may determine the merged DoF boundary based on a common intersection of the first basic DoF boundary and the second basic DoF boundary.

[0008] Each feature disclosed anywhere herein is described and may be implemented separately / individually and in any combination with any other feature disclosed herein and / or with any feature disclosed elsewhere which may be implicitly or explicitly mentioned herein or may otherwise fall within the scope of the subject matter disclosed herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1A is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented.

[0010] Figure 1B is an example of a method that can be used according to an embodiment of the present invention. Figure 1A A system diagram of an example wireless transmit / receive unit (WTRU) for use within an illustrated communication system.

[0011] Figure 1C is an example of a method that can be used according to an embodiment of the present invention. Figure 1A System diagram of an example Radio Access Network (RAN) and an example Core Network (CN) for use within the illustrated communication system.

[0012] Figure 1D is an example of a method that can be used according to an embodiment of the present invention. Figure 1A System diagram of an additional example RAN and an additional example CN for use within the illustrated communication system.

[0013] Figure 2 is a schematic diagram illustrating an example video encoder.

[0014] Figure 3 is a schematic diagram illustrating an example of a video decoder.

[0015] Figure 4is a schematic diagram illustrating an example of a system in which various aspects and examples may be implemented.

[0016] Figure 5 An example of a protagonist is shown, where the player controls a tracking camera behind the protagonist.

[0017] Figure 6 An example of a runtime processing model for user DoF control is shown.

[0018] Figure 7 An example of a runtime processing model for user DoF control is shown.

[0019] Figure 8 Shown is the DoF constraint associated with a volumetric asset.

[0020] Fig. 9 An example boundary extension at the content grid node level is shown.

[0021] Fig.10 An example of conventional node-level boundary expansion is shown.

[0022] Fig.11 An example of boundary expansion at the root node level is shown.

[0023] Fig.12 An example of boundary extension at the grid level is shown.

[0024] Fig.13 An example of the calculation of a merged DoF boundary is shown. DETAILED DESCRIPTION

[0025] A detailed description of exemplary embodiments will now be described with reference to the various drawings. Although this specification provides detailed examples of possible implementations, it should be noted that the details are intended to be illustrative and in no way limit the scope of the application.

[0026] Figure 1A1 is a diagram illustrating an example communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multiple access system that provides content such as voice, data, video, messaging, broadcast, etc. to multiple wireless users. The communication system 100 may enable multiple wireless users to access such content through sharing of system resources (including wireless bandwidth). For example, the communication system 100 may employ one or more channel access methods such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), zero tail unique word DFT spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multi-carrier (FBMC), etc.

[0027] like Figure 1A As shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, RAN 104 / 113, CN 106 / 115, public switched telephone network (PSTN) 108, Internet 110 and other networks 112, but it should be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d (any of which may be referred to as a “station” and / or “STA”) may be configured to send and / or receive wireless signals and may include user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular phone, a personal digital assistant (PDA), a smart phone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (IoT) device, a watch or other wearable device, a head-mounted display (HMD), a vehicle, a drone, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in an industrial and / or automated process chain environment), a consumer electronic device, a device operating on a commercial and / or industrial wireless network, etc. Any of the WTRUs 102a, 102b, 102c, and 102d may be interchangeably referred to as a UE.

[0028] The communication system 100 may also include a base station 114a and / or a base station 114b. Each of the base stations 114a, 114b may be any type of device that is configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106 / 115, the Internet 110, and / or other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node B, an eNode B, a Home Node B, a Home eNode B, a gNB, an NR Node B, a site controller, an access point (AP), a wireless router, and the like. Although the base stations 114a, 114b are each depicted as a single element, it should be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0029] Base station 114a may be part of RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as base station controllers (BSC), radio network controllers (RNC), relay nodes, etc. Base station 114a and / or base station 114b may be configured to send and / or receive wireless signals on one or more carrier frequencies (which may be referred to as cells (not shown)). These frequencies may be in a licensed spectrum, an unlicensed spectrum, or a combination of a licensed spectrum and an unlicensed spectrum. A cell may provide coverage of wireless services to a specific geographic area, which may be relatively fixed or may change over time. A cell may be further divided into cell sectors. For example, a cell associated with base station 114a may be divided into three sectors. Therefore, in one embodiment, base station 114a may include three transceivers, i.e., one transceiver for each sector of the cell. In an embodiment, base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to send and / or receive signals in a desired spatial direction.

[0030] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0031] More specifically, as noted above, the communication system 100 may be a multiple access system and may employ one or more channel access schemes such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, the base station 114a in the RAN 104 / 113 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may use Wideband CDMA (WCDMA) to establish the air interface 115 / 116 / 117. WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink (DL) Packet Access (HSDPA) and / or High Speed ​​UL Packet Access (HSUPA).

[0032] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE) and / or Advanced LTE (LTE-A) and / or Advanced LTE Pro (LTE-A Pro).

[0033] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR radio access, which may establish the air interface 116 using New Radio (NR).

[0034] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may together implement LTE radio access and NR radio access, for example using the dual connectivity (DC) principle. Thus, the air interface utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions transmitted to / from multiple types of base stations (e.g., eNBs and gNBs).

[0035] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi)), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), etc.

[0036] Figure 1A The base station 114b in the may be, for example, a wireless router, a Home NodeB, a Home eNodeB, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a local area, such as a business location, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a road, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a picocell or a femtocell. As Figure 1A As shown, base station 114b may have a direct connection to Internet 110. Therefore, base station 114b may not need to access Internet 110 via CN 106 / 115.

[0037] The RAN 104 / 113 may be in communication with the CN 106 / 115, which may be any type of network configured to provide voice, data, applications and / or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have different quality of service (QoS) requirements, such as different throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. The CN 106 / 115 may provide call control, billing services, mobile location-based services, prepaid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions, such as user authentication. Although not described in detail in the text, the CN 106 / 115 may be configured to provide voice, data, applications and / or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have different quality of service (QoS) requirements, such as different throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. The CN 106 / 115 may provide call control, billing services, mobile location-based services, prepaid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions, such as user authentication. Figure 1AAlthough not shown in the figure, it will be appreciated that the RAN 104 / 113 and / or the CN 106 / 115 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 / 113 or a different RAT. For example, in addition to being connected to the RAN 104 / 113, which may utilize NR radio technology, the CN 106 / 115 may also be in communication with another RAN (not shown) that employs GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or WiFi radio technology.

[0038] The CN 106 / 115 may also act as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and / or the Internet Protocol (IP) in the TCP / IP Internet protocol suite. The networks 112 may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, the networks 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 / 113 or a different RAT.

[0039] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communication system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks via different wireless links). Figure 1A The illustrated WTRU 102c may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0040] Figure 1B is a system diagram illustrating an example WTRU 102. Figure 1B As shown, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and / or other peripherals 138. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0041] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, etc. The processor 118 may perform signal decoding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although Figure 1B The processor 118 and the transceiver 120 are depicted as separate components, but it is understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0042] The send / receive element 122 may be configured to send a signal to a base station (e.g., base station 114a) or receive a signal from the base station via an air interface 116. For example, in one embodiment, the send / receive element 122 may be an antenna configured to send and / or receive an RF signal. In an embodiment, the send / receive element 122 may be a transmitter / detector configured to send and / or receive, for example, an IR signal, a UV signal, or a visible light signal. In another embodiment, the send / receive element 122 may be configured to send and / or receive both an RF signal and an optical signal. It should be understood that the send / receive element 122 may be configured to send and / or receive any combination of wireless signals.

[0043] Although the transmit / receive element 122 Figure 1B Although depicted as a single element in the figure, the WTRU 102 may include any number of transmit / receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0044] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and to demodulate signals received by the transmit / receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. For example, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11.

[0045] The processor 118 of the WTRU 102 may be coupled to and may receive user input data from a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. In addition, the processor 118 may access information from and store data in any type of suitable memory, such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, or the like. In other embodiments, the processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0046] The processor 118 may receive power from the power source 134, and may be configured to distribute power to and / or control power to the other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0047] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to or in lieu of the information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) over the air interface 116 and / or determine the WTRU's location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by any suitable location-determination method while remaining consistent with an embodiment.

[0048] The processor 118 may be further coupled to other peripherals 138, which may include one or more software modules and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, module, a frequency modulation (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a virtual reality and / or augmented reality (VR / AR) device, an activity tracker, etc. Peripheral device 138 may include one or more sensors, which may be one or more of the following: a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geolocation sensor; an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0049] The WTRU 102 may include a full-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with specific subframes for UL (e.g., for transmission) and downlink (e.g., for reception)) may be concurrent and / or simultaneous. The full-duplex radio may include an interference management unit for reducing and / or substantially eliminating self-interference via signal processing performed via hardware (e.g., a choke) or via a processor (e.g., a separate processor (not shown) or via processor 118). In an embodiment, the WRTU 102 may include a half-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with specific subframes for UL (e.g., for transmission) or downlink (e.g., for reception)) may be concurrent and / or simultaneous.

[0050] Figure 1C 1 is a system diagram illustrating the RAN 104 and the CN 106 in accordance with an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0051] The RAN 104 may include evolved Node-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of evolved Node-Bs while remaining consistent with an embodiment. The evolved Node-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the evolved Node-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the evolved Node-B 160a, for example, may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0052] Each of the evolved Node Bs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and / or DL, etc. Figure 1C As shown, the eNode-Bs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0053] Figure 1C The illustrated CN 106 may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (or PGW) 166. While each of the foregoing elements is depicted as being part of the CN 106, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0054] The MME 162 may be connected to each of the evolved Node-Bs 162a, 162b, 162c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation / deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and / or WCDMA.

[0055] The SGW 164 may be connected to each of the evolved Node-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring the user plane during inter-evolved Node-B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, and the like.

[0056] The SGW 164 may be connected to the PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0057] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include or may be in communication with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0058] Although the WTRU Figures 1A to 1D Although described as wireless terminals, it is contemplated that in certain representative embodiments, such terminals may (eg, temporarily or permanently) use a wired communications interface with a communications network.

[0059] In a representative embodiment, the other network 112 may be a WLAN.

[0060] A WLAN in infrastructure basic service set (BSS) mode may have an access point (AP) for the BSS and one or more stations (STA) associated with the AP. The AP may have access or an interface to a distribution system (DS) or another type of wired / wireless network that carries traffic to and / or out of the BSS. Traffic from outside the BSS to the STA may be reached by the AP and may be delivered to the STA. Traffic from the STA to a destination outside the BSS may be transmitted to the AP to be delivered to the corresponding destination. Traffic between STAs within the BSS may be transmitted by the AP, for example, where the source STA may transmit traffic to the AP, and the AP may deliver traffic to the destination STA. Traffic between STAs within the BSS may be considered and / or referred to as point-to-point traffic. Direct link establishment (DLS) may be used to transmit point-to-point traffic between the source STA and the destination STA (e.g., directly between them). In certain representative embodiments, the DLS may use 802.11e DLS or 802.11z tunnel DLS (TDLS). A WLAN using an independent BSS (IBSS) mode may not have an AP, and STAs (eg, all STAs) within or using the IBSS may communicate directly with each other. The IBSS communication mode may sometimes be referred to herein as an "ad hoc" communication mode.

[0061] When using the 802.11ac infrastructure operating mode or a similar operating mode, the AP may send beacons on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., a 20 MHz wide bandwidth) or a width dynamically set via signaling. The primary channel may be an operating channel of the BSS and may be used by the STA to establish a connection with the AP. In certain representative embodiments, carrier sense multiple access / collision avoidance (CSMA / CA) may be implemented, for example, in an 802.11 system. For CSMA / CA, a STA (e.g., each STA) (including the AP) may sense the primary channel. If the primary channel is sensed / detected and / or determined to be busy by a particular STA, the particular STA may fall back. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0062] High throughput (HT) STAs may communicate using a 40 MHz wide channel, for example, via a combination of a primary 20 MHz channel and adjacent or non-adjacent 20 MHz channels to form a 40 MHz wide channel.

[0063] Very high throughput (VHT) STA can support 20MHz, 40MHz, 80MHz and / or 160MHz wide channels. 40MHz channels and / or 80MHz channels can be formed by combining continuous 20MHz channels. 160MHz channels can be formed by combining 8 continuous 20MHz channels, or by combining two non-continuous 80MHz channels (this can be called 80+80 configuration). For 80+80 configuration, after channel coding, the data can pass through a segment parser that can divide the data into two streams. Each stream can be processed by inverse fast Fourier transform (IFFT) and time domain processing separately. These streams can be mapped to two 80MHz channels, and data can be sent by the transmitter STA. At the receiver of the receiver STA, the above-mentioned operation for the 80+80 configuration can be reversed, and the combined data can be transmitted to the medium access control (MAC).

[0064] 802.11af and 802.11ah support operating modes below 1GHz. Channel operating bandwidths and carriers are reduced in 802.11af and 802.11ah relative to those used in 802.11n and 802.11ac. 802.11af supports 5MHz, 10MHz, and 20MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11ah supports 1MHz, 2MHz, 4MHz, 8MHz, and 16MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah may support instrument type control / machine type communications, such as MTC devices in macro coverage areas. MTC devices may have certain capabilities, such as limited capabilities, including support for (e.g., only support for) certain bandwidths and / or limited bandwidths. MTC devices may include batteries with battery life above a threshold (e.g., to maintain very long battery life).

[0065] WLAN systems that can support multiple channels and channel bandwidths (such as 802.11n, 802.11ac, 802.11af, and 802.11ah) include channels that can be designated as primary channels. The primary channel may have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by a STA (which supports the minimum bandwidth operating mode) from all STAs operating in the BSS. In the example of 802.11ah, for STAs (e.g., MTC-type devices) that support (e.g., only support) a 1MHz mode, the primary channel may be 1MHz wide, even if the AP and other STAs in the BSS support 2MHz, 4MHz, 8MHz, 16MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) settings may depend on the state of the primary channel. If the primary channel is busy, for example, because a STA (which only supports a 1MHz operating mode) is transmitting to the AP, the entire available band may be considered busy even if most of the band remains idle and may be available.

[0066] In the United States, the available frequency band for 802.11ah is 902MHz to 928MHz. In South Korea, the available frequency band is 917.5MHz to 923.5MHz. In Japan, the available frequency band is 916.5MHz to 927.5MHz. The total bandwidth available for 802.11ah is 6MHz to 26MHz, depending on the country code.

[0067] Figure 1D 1 is a system diagram illustrating the RAN 113 and the CN 115 in accordance with an embodiment. As noted above, the RAN 113 may employ NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 113 may also be in communication with the CN 115.

[0068] The RAN 113 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 113 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, the gNBs 180a, 180b may utilize beamforming to send signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a may, for example, use multiple antennas to send wireless signals to and / or receive wireless signals from the WTRU 102a. In an embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on an unlicensed spectrum, while the remaining component carriers may be on a licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement coordinated multi-point (CoMP) technology. For example, the WTRU 102a may receive coordinated transmissions from the gNB 180a and the gNB 180b (and / or the gNB 180c).

[0069] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with scalable parameter sets. For example, OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or transmit time intervals (TTIs) of varying or scalable lengths (e.g., containing different numbers of OFDM symbols and / or continuously varying absolute time lengths).

[0070] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c while not accessing other RANs (e.g., such as the eNodeBs 160a, 160b, 160c). In a standalone configuration, the WTRUs 102a, 102b, 102c may use one or more of the gNBs 180a, 180b, 180c as mobility anchors. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration, the WTRU 102a, 102b, 102c may communicate / connect with the gNB 180a, 180b, 180c while also communicating / connecting with another RAN, such as the evolved Node-B 160a, 160b, 160c. For example, the WTRU 102a, 102b, 102c may implement the DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more evolved Node-Bs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the evolved Node-B 160a, 160b, 160c may act as a mobility anchor for the WTRU 102a, 102b, 102c, and the gNB 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRU 102a, 102b, 102c.

[0071] Each of the gNBs 180a, 180b, 180c may be associated with a specific cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in UL and / or DL, support of network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data towards a user plane function (UPF) 184a, 184b, routing of control plane information towards an access and mobility management function (AMF) 182a, 182b, etc. Figure 1D As shown, gNBs 180a, 180b, and 180c may communicate with each other via an Xn interface.

[0072] Figure 1DThe illustrated CN 115 may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one session management function (SMF) 183a, 183b, and possible data networks (DNs) 185a, 185b. Although each of the foregoing elements is depicted as part of the CN 115, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0073] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via the N2 interface and may act as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRU 102a, 102b, 102c, supporting network slicing (e.g., handling different PDU sessions with different requirements), selecting a specific SMF 183a, 183b, managing registration areas, terminating NAS signaling, mobility management, etc. The AMF 182a, 182b may use network slicing to customize CN support for the WTRU 102a, 102b, 102c based on the type of services utilized by the WTRU 102a, 102b, 102c. For example, different network slices may be established for different use cases, such as services relying on ultra-reliable low latency (URLLC) access, services relying on enhanced mobile broadband (eMBB) access, services for machine type communication (MTC) access, etc. The AMF 162 may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies, such as WiFi.

[0074] The SMF 183a, 183b may be connected to the AMF 182a, 182b via the N11 interface in the CN 115. The SMF 183a, 183b may also be connected to the UPF 184a, 184b via the N4 interface in the CN 115. The SMF 183a, 183b may select and control the UPF 184a, 184b, and configure the traffic routing through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions such as managing and allocating UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0075] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via the N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, etc.

[0076] The CN 115 may facilitate communications with other networks. For example, the CN 115 may include or may communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 115 and the PSTN 108. In addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to local data networks (DNs) 185a, 185b via the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and the N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0077] Given that Figures 1A to 1D as well as Figures 1A to 1D Corresponding to the description of the present invention, one or more or all of the functions described herein with reference to one or more of the following may be performed by one or more simulation devices (not shown): WTRU102a-102d, base station 114a-114b, evolved Node B 160a-160c, MME 162, SGW 164, PGW 166, gNB 180a-180c, AMF 182a-182b, UPF 184a-184b, SMF 183a-183b, DN 185a-185b and / or any other device described herein. The simulation device may be one or more devices configured to mimic one or more or all of the functions described herein. For example, the simulation device may be used to test other devices and / or simulate network and / or WTRU functions.

[0078] The simulation device may be designed to implement one or more tests of other devices in a laboratory environment and / or in an operator network environment. For example, one or more simulation devices may perform one or more functions or all functions while being fully or partially implemented and / or deployed as part of a wired and / or wireless communication network in order to test other devices within the communication network. One or more simulation devices may perform one or more functions or all functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. The simulation device may be directly coupled to another device for testing purposes and / or may use over-the-air wireless communications to perform testing.

[0079] One or more simulation devices can perform one or more (including all) functions without being implemented / deployed as part of a wired and / or wireless communication network. For example, the simulation device can be used in a test scenario in a test lab and / or a non-deployed (e.g., testing) wired and / or wireless communication network to implement testing of one or more components. One or more simulation devices can be test equipment. Direct RF coupling and / or wireless communication via RF circuits (e.g., which can include one or more antennas) can be used by the simulation device to send and / or receive data.

[0080] The present application describes a number of aspects, including tools, features, examples or embodiments, models, methods, etc. Many of these aspects are described in a particular manner, and at least in order to illustrate individual features, are usually described in a manner that may sound restrictive. However, this is for the clarity of description and does not limit the application or scope of these aspects. In fact, all different aspects can be combined and interchanged to provide further aspects. In addition, these aspects can also be combined and interchanged with the aspects described in the earlier submission.

[0081] The aspects described and contemplated in this application can be implemented in many different forms. Figures 5 to 8 Some embodiments may be provided, but other embodiments are also contemplated. Figures 5 to 8 The discussion of the present invention does not limit the breadth of specific implementations. At least one of these aspects generally relates to video encoding and decoding, and at least one other aspect generally relates to sending a generated or encoded bitstream. These and other aspects can be implemented as methods, apparatus, a computer-readable storage medium having stored thereon instructions for encoding or decoding video data according to any of the methods, and / or a computer-readable storage medium having stored thereon a bitstream generated according to any of the methods.

[0082] In this application, the terms "reconstruction" and "decoding" may be used interchangeably, the terms "pixel" and "sample" may be used interchangeably, and the terms "image", "picture" and "frame" may be used interchangeably.

[0083] Various methods are described herein, and each method in the method includes one or more steps or actions for implementing the method. Unless the correct operation method requires a specific order of steps or actions, the order and / or purposes of specific steps and / or actions can be modified or combined. Additionally, terms such as "first", "second", etc. can be used to modify elements, components, steps, operations, etc. in various embodiments, such as, for example, "first decoding" and "second decoding". Unless specifically required, the use of such terms does not imply the sequencing of the modified operation. Therefore, in this example, the first decoding does not need to be performed before the second decoding, and can, for example, occur before, during, or in overlapping time periods of the second decoding.

[0084] Various methods and other aspects described herein may be used to modify a module, such as Figure 2 and Figure 3 Pre-encoding process 201, intra prediction 260, entropy decoding 245 and / or entropy decoding module 330, intra prediction 360, post-decoding process 385 of video encoder 200 and video decoder 300 are shown respectively. In addition, the subject matter disclosed herein presents aspects that are not limited to VVC or HEVC, and can be applied to, for example, any type, format or version of video decoding (whether described in a standard or described in a recommendation, whether pre-existing or developed in the future), as well as any such standard and recommendation extension (e.g., including VVC and HEVC). Unless otherwise indicated or technically excluded, the aspects described in this application can be used alone or in combination.

[0085] Various numerical values ​​are used in the examples described in this application, such as minimum and maximum ranges (e.g., 0 to 1, 0 to N, or 0 to 255), bit values ​​for indication or determination, default values, ID numbers (e.g., for adaptive IDs), etc. These and other specific values ​​are for the purpose of describing the examples, and the described aspects are not limited to these specific values.

[0086] Figure 2 2 is a schematic diagram illustrating an example video encoder. Variations of the example encoder 200 are contemplated, but the following describes encoder 200 for clarity without describing all contemplated variations.

[0087] Before being encoded, the video sequence may undergo pre-encoding processing (201), such as applying a color transform to an input color picture (e.g., converting from RGB 4:4:4 to YCbCr 4:2:0), or performing a remapping of input picture components to obtain a signal distribution that is more resilient to compression (e.g., using histogram equalization of one of the color components). Metadata may be associated with the pre-processing and appended to the bitstream.

[0088] In encoder 200, a picture is encoded by encoder elements as described below. The picture to be encoded is partitioned (202) and processed in units such as coding units (CUs). Each unit is encoded, for example, using intra mode or inter mode. When a unit is encoded in intra mode, the unit performs intra prediction (260). Motion estimation (275) and compensation (270) are performed in inter mode. The encoder decides (205) which of intra mode or inter mode to use to encode the unit, and indicates the intra / inter decision by, for example, a prediction mode flag. The prediction residual is calculated, for example, by subtracting (210) the prediction block from the original image block.

[0089] The prediction residual is then transformed (225) and quantized (230). The quantized transform coefficients, along with motion vectors and other syntax elements, are entropy coded (245) to output a bitstream. The encoder may skip the transform and apply quantization directly to the untransformed residual signal. The encoder may bypass both the transform and quantization, i.e., directly code the residual without applying the transform or quantization process.

[0090] The encoder decodes the coded block to provide a reference for further prediction. The quantized transform coefficients are dequantized (240) and inverse transformed (250) to decode the prediction residual. The image block is reconstructed by combining the decoded prediction residual and the prediction block (255). An in-loop filter (265) is applied to the reconstructed picture to perform, for example, deblocking / SAO (sample adaptive offset) filtering to reduce coding artifacts. The filtered image is stored at a reference picture buffer (280).

[0091] Figure 3 300 is a schematic diagram illustrating an example of a video decoder. In the example decoder 300, a bitstream is decoded by a decoder element, as described below. The video decoder 300 generally performs the same Figure 2 The encoder 200 may also generally perform video decoding as part of encoding the video data. For example, the encoder 200 may perform one or more of the video decoding steps presented herein. The encoder reconstructs the decoded image, for example, to maintain synchronization with the decoder with respect to one or more of the following: reference pictures, entropy coding contexts, and other decoder-related state variables.

[0092] Specifically, the input of the decoder includes a video bitstream, which may be generated by the video encoder 200. First, the bitstream is entropy decoded (330) to obtain transform coefficients, motion vectors, and other decoded information. Picture partition information indicates how the picture is partitioned. Therefore, the decoder can divide (335) the picture according to the decoded picture partition information. The transform coefficients are dequantized (340) and inverse transformed (350) to decode the prediction residual. The image block is reconstructed by combining (355) the decoded prediction residual and the prediction block. The prediction block can be obtained (370) from intra-frame prediction (360) or motion compensated prediction (i.e., inter-frame prediction) (375). An in-loop filter (365) is applied to the reconstructed image. The filtered image is stored at a reference picture buffer (380).

[0093] The decoded picture may also undergo post-decoding processing (385), such as an inverse color transform (e.g., conversion from YCbCr 4:2:0 to RGB 4:4:4) or performing an inverse remapping that is the inverse of the remapping process performed in the pre-encoding process (201). The post-decoding processing may use metadata derived in the pre-encoding process and signaled in the bitstream.

[0094] Figure 4 It is a schematic diagram showing an example of a system in which various aspects and embodiments described herein can be implemented. System 400 may be embodied as a device, which includes various components described below and is configured to perform one or more aspects of the aspects described in this document. Examples of such devices include, but are not limited to, various electronic devices, such as personal computers, laptop computers, smart phones, tablet computers, digital multimedia set-top boxes, digital television receivers, personal video recording systems, interconnected home appliances, and servers. The elements of system 400 may be embodied in a single integrated circuit (IC), multiple ICs, and / or discrete components individually or in combination. For example, in at least one example, the processing elements and encoder / decoder elements of system 400 are distributed on multiple ICs and / or discrete components. In various embodiments, system 400 is coupled to one or more other systems or other electronic devices via, for example, a communication bus or by a dedicated input and / or output port communication. In various embodiments, system 400 is configured to implement one or more aspects of the aspects described in this document.

[0095] The system 400 includes at least one processor 410 configured to execute instructions loaded therein for implementing, for example, various aspects described in this document. The processor 410 may include embedded memory, input and output interfaces, and various other circuits as known in the art. The system 400 includes at least one memory 420 (e.g., a volatile memory device and / or a non-volatile memory device). The system 400 includes a storage device 440, which may include a non-volatile memory and / or a volatile memory, including but not limited to an electrically erasable programmable read-only memory (EEPROM), a read-only memory (ROM), a programmable read-only memory (PROM), a random access memory (RAM), a dynamic random access memory (DRAM), a static random access memory (SRAM), a flash memory, a magnetic disk drive, and / or an optical disk drive. As a non-limiting example, the storage device 440 may include an internal storage device, an attached storage device (including a removable and non-removable storage device), and / or a network accessible storage device.

[0096] The system 400 includes an encoder / decoder module 430, which is configured to process data, for example, to provide encoded video or decoded video, and the encoder / decoder module 430 may include its own processor and memory. The encoder / decoder module 430 represents a module that may be included in a device to perform encoding and / or decoding functions. As is well known, a device may include one or both of an encoding module and a decoding module. Additionally, the encoder / decoder module 430 may be implemented as a separate element of the system 400, or may be incorporated into the processor 410 as a combination of hardware and software known to those skilled in the art.

[0097] Program code to be loaded onto the processor 410 or the encoder / decoder 430 to perform various aspects described in this document may be stored in the storage device 440 and subsequently loaded onto the memory 420 for execution by the processor 410. According to various embodiments, one or more of the processor 410, the memory 420, the storage device 440, and the encoder / decoder module 430 may store one or more of the various items during the execution of the processes described in this document. Such stored items may include, but are not limited to, input video, decoded video or partially decoded video, bitstreams, matrices, variables, and intermediate or final results of processing equations, formulas, operations, and operation logic.

[0098] In some embodiments, memory internal to the processor 410 and / or encoder / decoder module 430 is used to store instructions and provide working memory for processing required during encoding or decoding. However, in other embodiments, memory external to the processing device (e.g., the processing device may be the processor 410 or the encoder / decoder module 430) is used for one or more of these functions. The external memory may be a memory 420 and / or a storage device 440, such as a dynamic volatile memory and / or a non-volatile flash memory. In several embodiments, the external non-volatile flash memory is used to store, for example, an operating system for the television. In at least one embodiment, a fast external dynamic volatile memory such as RAM is used as working memory for video coding and decoding operations, such as, for example, MPEG-2 (MPEG refers to Moving Picture Experts Group, MPEG-2 is also known as ISO / IEC 13818, and 13818-1 is also known as H.222, 13818-2 is also known as H.262), HEVC (HEVC refers to High Efficiency Video Coding, also known as H.265 and MPEG-H Part 2), or VVC (Versatile Video Coding, a new standard developed by the Joint Video Experts Group JVET).

[0099] Inputs to the elements of system 400 may be provided through various input devices as indicated in block 445. Such input devices include, but are not limited to: (i) a radio frequency (RF) section that receives an RF signal, such as that transmitted over the air by a broadcaster; (ii) a component (COMP) input terminal (or a set of COMP input terminals); (iii) a universal serial bus (USB) input terminal; and / or (iv) a high-definition multimedia interface (HDMI) input terminal. Other examples ( Figure 4 ) includes composite video.

[0100] In various embodiments, the input device of block 445 has associated corresponding input processing elements as known in the art. For example, the RF section may be associated with elements applicable to the following items: (i) selecting a desired frequency (also referred to as selecting a signal, or band limiting a signal to a frequency band), (ii) down-converting the selected signal, (iii) again band-limiting to a narrower frequency band to select a signal frequency band that may be referred to as a channel in some embodiments, (iv) demodulating the down-converted and band-limited signal, (v) performing error correction, and (vi) demultiplexing to select a desired packet stream. The RF section of various embodiments includes one or more elements for performing these functions, such as a frequency selector, a signal selector, a band limiter, a channel selector, a filter, a down-converter, a demodulator, an error corrector, and a demultiplexer. The RF section may include a tuner that performs various functions in these functions, including, for example, down-converting a received signal to a lower frequency (e.g., an intermediate frequency or a near-baseband frequency) or to baseband. In a set-top box embodiment, the RF part and its associated input processing element receive the RF signal that sends by wired (for example, cable) medium, and filter to required frequency band by filtering, down-conversion and again to perform frequency selection.Various embodiments rearrange the order of above-mentioned (and other) elements, remove some elements in these elements, and / or add other elements that perform similar or different functions.Adding element can include and insert element between existing element, for example, insert amplifier and analog-to-digital converter.In various embodiments, the RF part comprises antenna.

[0101] Additionally, the USB and / or HDMI terminals may include corresponding interface processors for connecting the system 400 to other electronic devices across the USB and / or HDMI connections. It should be understood that various aspects of input processing (e.g., Reed-Solomon error correction) may be implemented as needed, for example, in a separate input processing IC or in the processor 410. Similarly, various aspects of USB or HDMI interface processing may be implemented as needed in a separate interface IC or in the processor 410. The demodulated, error-corrected, and demultiplexed streams are provided to various processing elements, including, for example, the processor 410 and the encoder / decoder 430, which operate in conjunction with the memory and storage elements to process the data streams as needed for presentation on the output device.

[0102] The various components of system 400 may be disposed within an integrated housing. Within the integrated housing, the various components may be interconnected and data may be sent between the components using a suitable connection arrangement 425 (e.g., an internal bus known in the art, including an inter-IC (I2C) bus, wiring, and a printed circuit board).

[0103] System 400 includes a communication interface 450 that enables communication with other devices via a communication channel 460. Communication interface 450 may include, but is not limited to, a transceiver configured to send and receive data through communication channel 460. Communication interface 450 may include, but is not limited to, a modem or a network card, and communication channel 460 may be implemented, for example, within a wired and / or wireless medium.

[0104] In various embodiments, data is streamed or otherwise provided to the system 400 using a wireless network such as a Wi-Fi network, e.g., IEEE 802.11 (IEEE refers to the Institute of Electrical and Electronics Engineers). The Wi-Fi signals of these examples are received by a communication channel 460 and a communication interface 450 suitable for Wi-Fi communication. The communication channel 460 of these embodiments is typically connected to an access point or router that provides access to an external network (including the Internet) for allowing streaming applications and other over-the-top communications. Other embodiments provide streaming data to the system 400 using a set-top box that delivers data via an HDMI connection of an input box 445. Other embodiments provide streaming data to the system 400 using an RF connection of an input box 445. As described above, various embodiments provide data in a non-streaming manner. Additionally, various embodiments use a wireless network other than Wi-Fi, such as a cellular network or a Bluetooth network.

[0105] System 400 can provide output signals to various output devices, including display 475, speaker 485 and other peripherals 495. Display 475 of various embodiments includes one or more of, for example, a touch screen display, an organic light emitting diode (OLED) display, a curved display and / or a foldable display. Display 475 can be used for television, tablet computer, laptop computer, cellular phone (mobile phone) or other devices. Display 475 can also be integrated with other components (for example, as in a smart phone), or it can be independent (for example, an external monitor for a laptop computer). In various examples of embodiments, other peripherals 495 include one or more of an independent digital video disc (or digital versatile disc) (DVR, applicable to both terms), a disc player, a stereo system and / or a lighting system. Various embodiments use one or more peripherals 495, which provide functions based on the output of system 400. For example, a disc player performs the function of playing the output of system 400.

[0106] In various embodiments, control signals are communicated between the system 400 and a display 475, a speaker 485, or other peripherals 495 using signaling such as AV.Link, consumer electronics control (CEC), or other communication protocols that enable device-to-device control with or without user intervention. Output devices may be communicatively coupled to the system 400 via dedicated connections through respective interfaces 470, 480, and 490. Alternatively, output devices may be connected to the system 400 via a communication interface 450 using a communication channel 460. The display 475 and the speaker 485 may be integrated into a single unit with other components of the system 400 in an electronic device such as, for example, a television. In various embodiments, the display interface 470 includes a display driver such as, for example, a timing controller (T Con) chip.

[0107] For example, if the RF portion of input 445 is part of a separate set-top box, display 475 and speaker 485 may alternatively be separate from one or more of the other components. In various embodiments in which display 475 and speaker 485 are external components, output signals may be provided via dedicated output connections including, for example, an HDMI port, a USB port, or a COMP output.

[0108] These embodiments may be performed by computer software implemented by the processor 410 or by hardware or by a combination of hardware and software. As a non-limiting example, these embodiments may be implemented by one or more integrated circuits. The memory 420 may be of any type suitable for the technical environment and may be implemented using any appropriate data storage technology, such as, as a non-limiting example, optical memory devices, magnetic memory devices, semiconductor-based memory devices, fixed memory, and removable memory. The processor 410 may be of any type suitable for the technical environment and, as a non-limiting example, may include one or more of a microprocessor, a general-purpose computer, a special-purpose computer, and a processor based on a multi-core architecture.

[0109] Various implementations involve decoding. As used in this application, "decoding" may encompass, for example, all or part of a process performed on a received coded sequence to produce a final output suitable for display. In various embodiments, such processes include one or more processes typically performed by a decoder, such as entropy decoding, inverse quantization, inverse transform, and differential decoding. In various embodiments, such processes also include or alternatively include processes performed by decoders of various implementations described in this application, such as determining a first basic degree of freedom (DoF) boundary associated with a user, wherein the first basic DoF boundary is determined based on information prior to runtime and runtime information; determining a second basic DoF boundary associated with the user during runtime; determining a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary; and, conditional on the success of the determination of the merged DoF boundary, modifying an extended reality (XR) environment associated with the runtime based on the merged DoF boundary.

[0110] As additional embodiments, in one example, "decoding" refers only to entropy decoding, in another embodiment, "decoding" refers only to differential decoding, and in another embodiment, "decoding" refers to a combination of entropy decoding and differential decoding. Whether the phrase "decoding process" is intended to refer specifically to a subset of operations or broadly to a broader decoding process will be clear based on the context of the specific description and is considered to be well understood by those skilled in the art.

[0111] Various implementations involve encoding. In a manner similar to the discussion above about "decoding", "encoding" as used in this application may cover, for example, all or part of a process performed on an input video sequence to produce an encoded bitstream. In various embodiments, such processes include one or more processes typically performed by an encoder, such as partitioning, differential encoding, transforming, quantization, and entropy encoding. In various embodiments, such processes also include or alternatively include processes performed by encoders of various implementations described in this application, such as determining a first basic degree of freedom (DoF) boundary associated with a user, wherein the first basic DoF boundary is determined based on information before runtime and runtime information; determining a second basic DoF boundary associated with the user during runtime; determining a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary; and, conditional on the success of the determination of the merged DoF boundary, modifying an extended reality (XR) environment associated with the runtime based on the merged DoF boundary.

[0112] As another example, in one embodiment, "encoding" refers only to entropy encoding, in another embodiment, "encoding" refers only to differential encoding, and in yet another embodiment, "encoding" refers to a combination of differential encoding and entropy encoding. Whether the phrase "encoding process" refers specifically to a subset of operations or broadly to a broader encoding process will be clear based on the context of the specific description, and is believed to be well understood by those skilled in the art.

[0113] Note that the syntax elements used herein (such as may be indicated in Tables 1 to 5 and otherwise indicated in discussions or figures presented herein) are descriptive terms. Therefore, they do not exclude the use of other syntax element names.

[0114] When the figures are presented as flow charts, it should be understood that they also provide block diagrams of corresponding devices. Similarly, when the figures are presented as block diagrams, it should be understood that they also provide flow charts of corresponding methods / processes.

[0115] During the encoding process, a balance or trade-off between rate and distortion is usually considered, which often takes into account constraints of computational complexity. Rate-distortion optimization is usually expressed as minimizing a rate-distortion function, which is a weighted sum of rate and distortion. There are different methods to solve the rate-distortion optimization problem. For example, these methods can be based on extensive testing of all coding options (including all considered modes or decoding parameter values), and fully evaluate their decoding costs and the associated distortion of the reconstructed signal after decoding and decoding. Faster methods can also be used to reduce coding complexity, especially for the calculation of approximate distortion based on prediction or prediction residual signals rather than reconstructed residual signals. A mixture of these two methods can also be used, such as by using approximate distortion for only some of the possible coding options, and using full distortion for other coding options. Other methods only evaluate a subset of possible coding options. More generally, many methods use any of a variety of techniques to perform optimization, but optimization is not necessarily a complete evaluation of both decoding costs and associated distortions.

[0116] The specific implementations and aspects described herein may be implemented in, for example, methods or processes, devices, software programs, data streams, or signals. Even if discussed only in the context of a single form of specific implementation (e.g., discussed only as a method), the specific implementation of the features discussed may also be implemented in other forms (e.g., devices or programs). Devices may be implemented in, for example, appropriate hardware, software, and firmware. These methods may be implemented in, for example, a processor, which generally refers to a processing device, including, for example, a computer, a microprocessor, an integrated circuit, or a programmable logic device. Processors also include communication devices, such as, for example, computers, mobile phones, portable / personal digital assistants ("PDAs"), and other devices that facilitate information communication between end users.

[0117] Reference to "one embodiment," "an embodiment," "an example," or "an implementation," or "an implementation," and other variations thereof, means that a particular feature, structure, characteristic, etc. described in connection with the embodiment is included in at least one embodiment. Thus, the appearance of the phrases "in one embodiment," "in an embodiment," "in an example," or "in an implementation," or "in an implementation," and any other variations thereof in various places throughout this application are not necessarily all referring to the same embodiment or example.

[0118] Additionally, the present application may involve "determining" various information. Determining information may include, for example, estimating information, calculating information, predicting information, or retrieving information from a memory. Obtaining may include receiving, retrieving, constructing, generating, and / or determining.

[0119] Furthermore, the present application may refer to "accessing" various information. Accessing information may include, for example, one or more of receiving information, retrieving information (e.g., from a memory), storing information, moving information, copying information, calculating information, determining information, predicting information, or estimating information.

[0120] Additionally, the present application may involve "receiving" various information. Like "accessing," receiving is intended to be a broad term. Receiving information may include, for example, one or more of accessing information or retrieving information (e.g., from a memory). Moreover, "receiving" generally involves, in one way or another, during operations such as, for example, storing information, processing information, sending information, moving information, copying information, erasing information, calculating information, determining information, predicting information, or estimating information.

[0121] It should be understood that, for example, in the case of "A / B," "A and / or B," and "at least one of A and B," the use of any of the following " / ," "and / or," and "at least one of" is intended to encompass selecting only the first listed option (A), or selecting only the second listed option (B), or selecting both options (A and B). As a further example, in the case of "A, B, and / or C" and "at least one of A, B, and C," such phrases are intended to encompass selecting only the first listed option (A), or selecting only the second listed option (B), or selecting only the third listed option (C), or selecting only the first listed option and the second listed option (A and B), or selecting only the first listed option and the third listed option (A and C), or selecting only the second listed option and the third listed option (B and C), or selecting all three options (A and B and C). This can be extended to as many items as listed, as would be apparent to one of ordinary skill in the art and related arts.

[0122] Moreover, as used herein, the word "signaling" especially refers to indicating something to the corresponding decoder. For example, in some embodiments, the encoder (e.g., to the decoder) signals MPD, adaptation set, representation, preselection, G-PCC component, G-PCCComponent descriptor, G-PCC descriptor or basic attribute descriptor, supplementary attribute descriptor, G-PCC tile inventory descriptor, G-PCC static space region descriptor, GPCCTileId descriptor, GPCC3DRegionID descriptor, other descriptors, elements and attributes, metadata, mode, etc. (e.g., as disclosed herein, included in Table 1 to Table 5). In this way, in the embodiment, the same parameters are used at both the encoder side and the decoder side. Therefore, for example, the encoder can send (explicit signaling) specific parameters to the decoder so that the decoder can use the same specific parameters. On the contrary, if the decoder already has specific parameters and other parameters, signaling can be used without sending (implicit signaling) to simply allow the decoder to know and select specific parameters. By avoiding sending any actual function, bit saving is achieved in various embodiments. It should be understood that signaling can be implemented in a variety of ways. For example, in various embodiments, one or more grammatical elements, flags, etc. are used to signal information to the corresponding decoder. Although the verb form of the word "signaling" is mentioned above, the word can also be used as the noun "signal" in this article.

[0123] It will be apparent to one of ordinary skill in the art that a specific implementation may generate a variety of signals formatted to carry, for example, storable or transmittable information. The information may include, for example, instructions for executing a method or data generated by one of the described specific implementations. For example, a signal may be formatted to carry a bit stream of the described embodiment. Such a signal may be formatted as, for example, an electromagnetic wave (e.g., using a radio frequency portion of a spectrum) or a baseband signal. Formatting may include, for example, encoding a data stream and modulating a carrier using the encoded data stream. The information carried by the signal may be, for example, analog or digital information. As is well known, the signal may be sent over a variety of different wired or wireless links. The signal may be stored on a processor readable medium.

[0124] In extended reality (XR) applications, user movement may be defined as degrees of freedom (DoF), which may be affected (e.g., limited) by one or more of the following constraints: the capabilities allowed for the user in the XR experience; viewing restrictions for the XR asset (e.g., volumetric video streams or other media assets with limited viewing angles due to an inherited capture configuration); the type of XR experience associated with the dedicated user movement; the performance of spatial tracking implemented to provide accurate user pose estimation at runtime; and / or the available space in which the user can move freely and safely. The capabilities allowed for the user in the XR experience may include 6DoF capabilities and / or 3DoF capabilities. XR games may include modes, such as a player mode and a spectator mode. Two or more participants may join to play an XR game in a player mode. Spectators may join to watch an XR game in spectator mode. Participants in player mode may have DoF capabilities (e.g., 6DoF capabilities) to move freely within the room. Participants in spectator mode may have modified DoF capabilities (e.g., 3 capabilities) to watch participants in player mode play the game. Viewing of one or more XR assets or other media assets, such as volumetric video streams (e.g., MPEG Point Cloud Compression (PCC), MPEG Immersive Video (MIV), etc.), may have a limited viewing angle due to an inherited capture configuration. Types of XR experiences (e.g., requiring dedicated user movement) may include, for example, an XR racing simulator that may use a seated user, an XR dance game that may use room-scale user movement, and / or a museum tour XR experience that may use world-scale user movement. The performance of spatial tracking to provide accurate user pose estimation at runtime may include different types of tracking that exist, such as outside-in, inside-out, world tracking, simultaneous localization and / or mapping (SLAM), etc. The available space may be a space in which a user may move freely and safely, which may be related to a fully immersive virtual reality (VR) experience in which the user cannot see their real (e.g., their physical) surroundings.

[0125] The constraints described herein may be static. For example, a set of constraints may not change during an XR experience. Viewing (e.g., viewing restrictions) and spatial tracking performance from volumetric assets may be known before the application is run. Constraints may be timed. For example, a set of constraints may be expected to be applied at a given time instance during the playback of an XR experience. The timing of the playback of timed constraints may be encapsulated by means other than scene description. The capabilities of a user representation may evolve based on the time over which the XR experience has passed. A user representation (e.g., an avatar / camera) may follow a predefined path within a virtual world. Constraints may be non-timed. For example, a set of constraints may be applied (e.g., expected to be applied) when an event occurs during the playback of an XR experience. The triggering of constraints may be encapsulated by means other than scene description. Available space may be modified at runtime due to changes (e.g., any changes) in the user's real environment (e.g., accurate estimates of available space, displacement of real objects, etc.). The user's capabilities may evolve based on user actions at runtime (e.g., gaining experience, finding specific virtual items, etc.). These events may be predefined within an XR interaction framework that includes a combination of triggers and actions.

[0126] Constraints can define different limited ranges for DoF for users experiencing different use cases. For example, when multiple users share a common XR experience (e.g., in unison), a framework can be used to define and control multiple DoF boundaries.

[0127] A player in an XR experience may observe the XR experience in different examples. In an example, the XR experience may be observed from the perspective of a protagonist (such as a first-person shooter game). In an example, the protagonist may be viewed on a screen during gameplay (such as in a third-person shooter game). The user experience mode in the first form may be referred to herein as viewer, and the user experience mode in the second form may be referred to herein as “viewer+avatar,” where an avatar is a model of the protagonist playing the game (e.g., a Figure 5 shown).

[0128] DoF constraints may apply to one case (e.g., individual cases) and / or multiple cases (e.g., multiple cases in combination). Where two forms of user experience modes are considered, the term "user representation" may be used. In an example, one user (e.g., represented via an avatar or camera in a 3D scene) may have the ability to fly, and another user may have the ability to crawl.

[0129] Figure 5 An example of a protagonist is shown, where the player controls a tracking camera located directly behind the protagonist. The DoF constraint may include a DoF boundary. The DoF boundary may be represented by a bounded volume. Within the bounded volume, the DoF constraint may be applicable.

[0130] A framework may be used to control the DoF boundaries of users sharing an XR experience. The framework may include one or more of the following: determining a base boundary based on the user's DoF constraints; calculating a merged DoF boundary for the user; or controlling user movement relative to a merged DoF boundary (e.g., if the user reaches an allowed boundary or if the calculation indicates that no merged DoF boundary is possible, one or more predefined actions may be initiated).

[0131] XR scene description semantics may be enhanced to provide, for example, predefined data associated with a framework. For example, at the scene level, predefined data may be common to users (e.g., all users) to avoid data duplication, such as data related to spatial tracking performance when users (e.g., all users) have the same type of XR device, and / or data related to available space when users (e.g., all users) share the same real environment. For user representations in scene descriptions (e.g., user representations that may involve avatars / cameras), user-specific predefined data may be included as data related to user mobility capabilities in addition to conventional user representation data in the XR experience (e.g., view frustum, avatar size, mesh colliders).

[0132] A scene description framework using the Khonos glTF extension mechanism may be utilized in conjunction with one or more of the features described herein. Figure 6 As shown, a runtime processing model can be shown to users sharing an XR experience.

[0133] Figure 6 An example block of a technique for managing DoF boundaries within an XR environment is illustrated. At 602, an initialization phase can be performed. The initialization phase can establish parameters and data structures associated with performing the technique. At 604, a base DoF boundary can be determined. For example, analysis can be performed on data input from a source such as user settings, sensor data, or system configuration. At 606, a merged DoF boundary can be calculated. A merged DoF boundary can be calculated based on a subset of the base boundaries, for example, integrated into a comprehensive boundary. One or more merged DoF boundaries can be utilized to guide the movement of a user within the XR environment.

[0134] At 608, a check may be made to determine whether the calculation of the merged boundary was successful. If the calculation of the merged boundary was not successful, as indicated by the path labeled "No" to 610, a boundary failure action may be initiated. The calculation of the merged boundary may not be successful, which may occur if no common intersection volume between the base boundaries is found; a boundary failure action may be initiated.

[0135] The boundary failure actions that may be initiated at 610 may include displaying an error message before terminating the application at 612. A user may have their own boundary failure actions that are referenced in the user's representation (e.g., avatar / camera) glTF extension via the boundaryFailedActions parameter. The boundaryFailedActions parameter may include a set of numbers corresponding to actions defined in the interaction framework, and may look similar to "boundaryFailedActions".

[0136] At 610, in the case of a boundary failure action, the technique may stop at 612. If the calculation of the merged boundary at 608 is successful, as indicated by the path labeled "yes" to 614, the user's movement within the XR environment may be controlled relative to the merged DoF boundary. At 616, calculations may be performed to evaluate whether the user has reached the merged boundary. If the user has reached the boundary, as indicated by the path labeled "yes" to 618, a boundary reached action may be initiated.

[0137] At 618, once the boundary arrival action has been initiated, or if the user has not reached the merged boundary at 616, it can be determined whether the DoF boundary is static at 620. At 620, if the boundary is static, as represented by the path labeled "Yes" returning to 614, then control of user movement within the XR environment based on the merged DoF boundary can be maintained. If the boundary is not static, as indicated by the path labeled "No" returning to 604, then the process of determining the basic degree of freedom boundary can be restarted.

[0138] Figure 6 An example of a runtime processing model for user DoF control is shown. The processing model may include one or more of: determining a base DoF boundary; calculating a merged DoF boundary; and / or controlling user movement relative to a merged DoF boundary.

[0139] A determination of basic DoF boundaries may be provided. For the user, the DoF constraints that trigger the determination of basic DoF boundaries may be based on a set of inputs. There may be multiple (e.g., two) DoF constraints, which may include one or more of the following. The constraints may include DoF constraints defined before the runtime of the application, which may be calculated by preprocessing techniques. Information about DoF constraints may be provided to the application for the user to experience the XR scene. For example, pre-calculated DoF constraints may be used so that the user representation can move freely and safely. The DoF constraints may have been calculated based on a scanned representation of the user environment (e.g., or based on other means). The pre-calculated DoF constraints may be a restricted viewing space associated with a 3D object represented by the user. The constraints may include DoF constraints defined by the application at runtime. The application may rely on an XR framework such as OpenXR to determine the DoF constraints.

[0140] DoF constraints defined before runtime may be provided. Predefined data for constrained DoF may be provided in an XR scene description file. The XR scene description file may be the entry point for a user's application to run and render an XR experience. To provide data about constrained DoF, the XR scene description file may be enhanced by adding a glTF extension.

[0141] Figure 7 An example block diagram of a technique for managing DoF boundaries within an XR environment is illustrated. At 702, there may be an initialization process. The initialization process may set system parameters and data structures for the technique. At 704, basic DoF boundaries defined prior to runtime may be determined. These boundaries may be based on preset configurations, system settings, or user preferences. At 706, basic DoF boundaries defined at runtime may be determined. Basic DoF boundaries defined at runtime may involve using real-time inputs, such as sensor data or user interactions.

[0142] At 708, it may be determined whether the base DoF boundary is determined both before and at runtime. If the base DoF boundary is determined both before and at runtime, as indicated by the path marked “yes” to 710, the final base DoF boundary may be calculated. At 712, a merged DoF boundary may be calculated based on the base boundary and the final base DoF boundary. At 714, a check may be performed to assess whether the calculation of the merged boundary was successful. If the calculation is unsuccessful, as indicated by the path marked “no” to 716, a boundary failure action may be initiated. The boundary failure action that may be initiated at 716 may include displaying an error message or modifying the base DoF boundary to create a valid merged boundary. These modifications may include user instructions to modify the user's surroundings, adjustments to gestures or certain volumetric assets, and / or changes to DoF constraints related to the user's representation capabilities (e.g., removing portions related to the user's physical surroundings from the XR scene).

[0143] At 718, it may be determined whether a new merged DoF boundary may be calculated. If a merged DoF boundary is not calculated (e.g., cannot be calculated, or cannot be accurately calculated), as indicated by the path labeled "No" to 720, the process may stop. At 720, if the calculation of the new merged DoF boundary is unsuccessful, the process may terminate and an error message may be displayed. If the calculation of the new merged DoF boundary is successful, as indicated by the path labeled "Yes" to 722, user movement within the XR environment may be controlled relative to the merged DoF boundary. Interactions within the XR environment (e.g., interactions in addition to interactions allowed before the new merged DoF boundary was calculated) may be allowed because the new merged DoF boundary may provide a larger space for user interaction. The calculation of the new merged DoF boundary may enable rendering (e.g., more refined rendering) because an accurate (e.g., more accurate) understanding of the available physical space may be available. The calculation of the new merged DoF boundary may enable safety features, such as an alert or visual indication when a user approaches the merged DoF boundary.

[0144] At 722, after controlling the user to move, an evaluation can be made at 724, whether the user has reached the merged boundary. At 724, if the user has reached the merged boundary, as indicated by the path marked as "yes" to 726, a boundary reaching action can be initiated.

[0145] At 726, once the boundary reach action has been initiated, or if the user has not reached the merged boundary at 724, it can be determined whether the DoF boundary is static at 728. At 728, if the boundary is static, as indicated by the path labeled "Yes" returning to 722, user movement can continue to be controlled based on the merged DoF boundary. If the boundary is not static, as indicated by the path labeled "No" returning to 704, determining the basic degree of freedom boundary previously defined at runtime can be started again.

[0146] For DoF constraints based on volumetric assets, there may be a volumetric asset that is a partial representation of a volumetric scene or a volumetric 3D object. If the volumetric asset cannot be used by a viewer in an unbounded space, the volumetric asset may provide parameters about a restricted viewing space in which the user may have a viewing experience (e.g., an optimal viewing experience) of the volumetric asset.

[0147] In an example, if a 3D object is partially captured, the 3D object author's intention may be to not allow the user to view the 3D object surface where capture was not performed. Not allowing the user to view the 3D object may result in limited user movement within the bounded volume, because corresponding data for the 3D object may not exist in the view outside the bounded volume. Figure 8 The potential bounding volume can be shown in .

[0148] Figure 8 An example of a DoF constraint from a volumetric asset is shown. The DoF constraint can be represented as an extension to a node. The node can refer to a camera representing a scene in "viewer" mode, or the extension of the node can refer to a protagonist representing a scene in "viewer+avatar" mode. In the example, DoF constraints can be provided to XR applications by adding a glTF extension at the mesh level representing a 3D object.

[0149] There may be a variety of techniques for providing DoF constraints. For example, the coordinates of the DoF boundary may be provided by one or more of the following. The coordinates may be provided by a mesh object in a glTF file. The mesh object may represent a bounded volume geometry. The data for the bounded volume geometry may be embedded with the 3D object itself or may be provided by external means. The coordinates may be provided by parameters representing the bounded volume. There may be a variety of types of bounded volumes, such as cuboids, spheres, and the like. For a cuboid, the parameters may include vertex positions. For a sphere, the parameters may include the radius of the bounded sphere. These parameters may affect the user's movement and restrict the user to a viewing space enclosed within the DoF boundary.

[0150] The user's orientation may be constrained within a bounding volume. In an example, a minimum rotation angle and a maximum rotation angle may be provided. Rotations in glTF files may be represented by quaternions.

[0151] In an example, when a bounding volume is attached to a viewer node or an avatar node, the bounding volume and DoF constraints may be expressed in the world coordinate space of the XR scene.

[0152] Fig. 9 An example bounding extension at the content mesh node level is shown. In an example, when a bounding volume is attached as an extension to a regular node, the regular node may refer to a mesh 3D object, such as Fig. 9 The coordinate space of the bounded geometry can be the same as the coordinate space of the mesh 3D object. There may be an implicit offset between the 3D object geometry and the bounded volume geometry. Bounded volumes and DoF constraints can be applied to attached nodes (e.g. Fig. 9 DoF constraints can be applied to the children of regular nodes.

[0153] Fig.10 An example of bounding extension at the regular node level is shown. In the example, if a bounding volume is attached as an extension to a regular node in the node hierarchy, then another regular node (e.g., Fig.10 The nodes in 2) can refer to mesh 3D objects, such as Fig.10 The coordinate space of the bounded geometry may be different from the coordinate space of the mesh 3D object, because both geometries may follow the coordinate space of the node they inherit from. Fig.10 Provides bounded volume and DoF constraints in the local coordinate space of the node in 1). DoF constraints can be applied to the child nodes of a regular node.

[0154] Fig.11 An example of bounds extension at the root node level is shown. In the example, when a bounded volume is attached to the root node as an extension, a regular node (e.g. Fig.11 The nodes in 2) can refer to mesh 3D objects, such as Fig.11 The coordinate space of the bounded geometry can be the same as the coordinate space of the root node. Fig.11 Provides bounding volume and DoF constraints in the local coordinate space of the root node in .

[0155] Fig.12 An example of grid-level boundary expansion is shown. In the example, Fig.12 As shown, if a bounded volume is attached to a mesh as an extension, the coordinate space of the bounded geometry can be the same as the coordinate space of the mesh 3D object. There may be an implicit offset between the 3D object geometry and the bounded volume geometry. This can be done at the attachment node (e.g., Fig.12 The bounded volume and DoF constraints are provided in the local coordinate space of the node 1).

[0156] In an example, DoF constraint data may be embedded in the volume asset format. The XR application may retrieve the DoF constraints after the decoding step. For example, an immersive video (e.g., MIV) may define viewing space metadata corresponding to viewing domain constraints. The XR application may calculate the relevant DoF boundaries based on the provided metadata. The data of the DoF boundaries may be provided as a patch update to the scene description file. The patch update may update the scene description to generate a syntax as described herein.

[0157] Content may have DoF characteristics. Content may adopt DoF constraints that are different from those of the main scene. In an example, a viewer may freely perform 6DoF movements within the viewing space. In an example, binoculars may be positioned in the scene. The viewer may want to view from the binoculars. To simulate the conditions of a viewer viewing from binoculars, a 360-degree video may be displayed. The viewer may interact with the scene and choose to observe from the perspective of the binoculars. Upon selection, the viewer's DoF is changed to a content-specific DoF, for example, 3DoF in the case of a 360-degree video. The rotation of the viewer's head movement is recorded and registered by the application. The rotation of the viewer's head movement corresponds to the rotation at which the frame will be rendered. Content may explicitly specify the range of rotations possible for content rendering. Viewers who intend to rotate beyond this range may trigger an interaction, thereby initiating an action. The relationship between actions and interactions may be specified in an extension.

[0158] The user may move around in their physical environment. Translational movements may be recorded. Translational movements in the case of 360-degree video may have no effect on rendering, as the content may support 3DoF. The XR runtime may monitor the user's recorded translational movements to determine that the user is within the bounds of the restricted viewing space conveyed by the main scene. If the user translates out of the viewing space, the translation may be recorded as an interaction. Appropriate actions for interactions may be specified in the extension.

[0159] When the viewer intends to exit from the binocular experience, the scene DoF constraints may take over. The user may be positioned back to the scene from which the user entered the binocular experience. The viewer's gesture movements may be recorded and registered to provide correct rendering of the scene frame. Frame rendering may be controlled by the user's translation and rotation properties.

[0160] The content may correspond to a 6DoF constraint. The properties of the 6DoF constraint of the content may be different from the properties of the parent 6DoF properties of the scene or scene object in the hierarchy described herein. The DoF constraint of the element in the leaf node may take precedence.

[0161] Table 1 may represent the semantics of an extension representing a DoF constraint that includes information related to the DoF boundary.

[0162] Table 1: MPEG_mesh / node_boundary_extension

[0163]

[0164]

[0165]

[0166] For DoF constraints derived from the type of XR application and / or the performance of the user tracking system, the type of XR application and / or the performance of the user tracking system may affect the user movement to allow accurate pose estimation.

[0167] Multiple user constraint spaces may be provided, which may be referred to as XR reference spaces. In an example, multiple user constraint spaces may be provided, for example, using the OpenXR framework and / or the WebXR framework. In an example, the characteristics of the WebXR reference space may include one or more of the following. A local reference space may correspond to a seated XR experience (e.g., an immersive 2D video viewer, a racing simulator, and / or a solar system explorer) that may not involve a user moving around in space. It may correspond to 3DoF / 3DoF+user constraints associated with user head movement. A bounded reference space may correspond to a room-level XR experience (e.g., an XR dance game, VR painting / sculpting, etc.), where a user moves around in their physical environment beyond fixed boundaries to interact with virtual content (e.g., fully interactive). A bounded reference space may correspond to a constrained 6DoF. The boundaries may be fixed and pre-established, depending on the space of the XR experience (e.g., spatial requirements). Unbounded reference space may correspond to a world-class XR experience (e.g., a museum visit, a city tour, etc.) where the user is free to move around and travel a certain distance in their physical environment. Unbounded reference space may correspond to 6DoF with no boundaries (e.g., or with infinite boundaries). Geospatial tracking systems can be used for outdoor XR experiences. View reference space may correspond to an XR experience (e.g., a heads-up display of information, a furniture viewer that uses click and drag controls to look around, etc.) where the XR content can stay at a fixed point so that it looks like there is no tracking. The origin of the reference space can (e.g., can always) be at the posture of the viewer device. User DoF constraints may depend on the performance of the user tracking system.

[0168] DoF constraints can be provided to XR applications by adding glTF extensions, for example, at the scene level (in the case where users (e.g., all users) have the same type of reference space) or at the user representation (e.g., avatar / camera) level for a dedicated user reference space. The type of reference space between local view type, bounded view type, and unbounded view type can be provided using enumerators or explicit text.

[0169] For local reference space and bounded reference space, boundary parameters can be defined. DoF constraints can be provided in one or more of the following examples. The coordinates of the DoF boundary can be provided by a mesh object in a glTF file. The mesh object can represent a bounded volume geometry. Coordinates can be provided by parameters representing the bounded volume. There can be many types of bounded volumes, such as a cuboid, a sphere, etc. For a cuboid, the parameters can include the global position of the vertices. For a sphere, the parameter can be the radius of the bounded sphere.

[0170] Table 2 illustrates an example of providing data in the XR application world space.

[0171] Table 2: Providing data in the XR application world space .

[0172]

[0173]

[0174]

[0175] DoF constraints may be related to available space. The available space in which a user can move freely and safely may be known before runtime based on analysis of a scanned representation of the real environment. For example, the largest area of ​​the ground surface free of obstacles (e.g., any obstacles) may be determined during a previous calculation by performing one or more of the following: by iterating over the scanned mesh vertices and by identifying vertices with the same height (e.g., the same lowest y coordinate); by computing contours that enclose different ground surface region candidates; or by taking the largest area between region candidates (e.g., all region candidates).

[0176] The resulting area may be defined by a polygonal outline comprising connected vertices. The height of a ceiling or hanging obstacles (e.g., any hanging obstacles) above the resulting maximum area may be determined to identify the available 3D space. The available space boundaries may be provided in a scene description file.

[0177] Available space constraints may be provided to XR applications by adding glTF extensions, for example, at the scene level (in the case where users share the same real environment) or at the level of the user representation (e.g., avatar / camera) of the real environment for a dedicated user. There may be multiple ways of representing DoF constraints. For example, the coordinates of the DoF boundaries may be provided by a mesh object in a glTF file. The mesh object may represent a bounding volume geometry. The coordinates may be provided by parameters representing the bounding volume. There may be different types of bounding volumes, such as a cuboid, a sphere, etc. For a cuboid, the parameters may include the vertex global position. For a sphere, the parameter may be the radius of the bounding sphere.

[0178] Table 3 illustrates an example of providing data in the XR application world space.

[0179] Table 3: Providing data in the XR application world space

[0180]

[0181]

[0182] With respect to DoF constraints related to user representation capabilities in an XR experience, a user representation may not have the same DoF in an XR experience. In an example, a user representation may be allowed to walk around (e.g., everywhere) in a virtual world. A user representation may be allowed to walk around within a single room. A user representation may fly, and a user representation may crawl, etc.

[0183] The constraints may be one or more of the following. Constraints may be static (e.g., because the constraints do not change during the XR experience). Constraints may be timed (e.g., applied at a given time instance as expected during playback of the XR experience). The capabilities of the user representation may evolve based on the time that the XR experience passes. The user representation may follow a predefined path within the virtual world. The constraints may be untimed constraints, which are expected to apply when events occur during playback of the XR experience. The user's capabilities may evolve based on user actions at runtime (e.g., gaining experience, finding a specific virtual item, etc.). Events may be predefined within the XR interaction framework that includes a combination of triggers and actions.

[0184] Table 4 illustrates example semantics of actions related to modification of user capabilities at runtime.

[0185] Table 4: Semantics of actions related to modification of user capabilities at runtime .

[0186]

[0187] Capabilities constraints with one or more of the following parameters may be provided to the XR application by adding a glTF extension at the user representation (e.g., avatar / camera) level. The capabilitiesBoundaries parameter may define the vertex coordinates of the bounds represented in the XR application world space. These coordinates may be provided by a mesh object in the glTF file. A mesh object may represent a bounded volume geometry. The coordinates may be provided by parameters representing the bounded volume. There may be different types of bounded volumes, such as a cuboid, a sphere, and the like. For a cuboid, the parameters may include the vertex global position. For a sphere, the parameter may be the radius of the bounded sphere. The capabilitiesTimeBehavior parameter may define the time behavior of the bounds using an enumeration or explicit text between static behavior, timed behavior, or non-timed behavior. If a timedcapabilitiesTimeBehavior is defined, the timing data may be provided by one or more of the following. The timing data may be provided by the capabilitiesTimedAccessor parameter indicating an associated accessor with the MPEG_accessor_timed extension in the glTF accessor array or by the capabilitiesMediaSource parameter indicating an associated media in the MPEG_media extension. When the capability data evolves on a per-frame basis, the capabilitiesTimedAccessor parameter may be used. When the capability data evolves on a predefined timestamp basis, such as a composition timestamp (CTS) (e.g., as shown in Table 5), the capabilitiesMediaSource parameter may be used. The capability data associated with the capabilitiesMediaSource parameter may be provided in a JSON file with mimetype equal to "application / json".

[0188] Table 5

[0189]

[0190]

[0191] DoF constraints may be defined at runtime. One or more DoF constraints may be determined at runtime by the XR application using a dedicated XR framework (e.g., OpenXR). In an example, when the scanned environment is not analyzed in a previous step (e.g., before runtime), the available space in which the user representation can move freely and safely may be determined.

[0192] The application can rely on the OpenXR API and the GetReferenceSpaceBoundsRect() technique to calculate the available space.

[0193] In an example, the DoF constraints may be determined based on both pre-runtime information and runtime information.

[0194] In an example, available space within which a user can move freely and safely may be determined. The current user environment may be evolving over time and may have changed from scanned data manipulation completed previously at runtime (e.g., a table or chair has been moved). The relevant DoF bounds may not be consistent between predefined information (e.g., provided in a scene description file) and runtime information (e.g., provided from the GetReferenceSpaceBoundsRect() OpenXR API).

[0195] Calculations may be used to determine the final relevant DoF bounds. Techniques for calculation may be used such as: ignoring DoF constraints previously determined at runtime and taking the most recent DoF constraint provided at runtime; and / or taking the common intersection volume between the 2 DoF constraints.

[0196] A calculation of a merged DoF boundary may be provided. The merged DoF boundary of the user representation may correspond to a common intersection volume between the basic boundaries (eg, all basic boundaries) determined in the techniques described herein, such as Fig.13 shown.

[0197] Fig.13 An example of calculation of a merged DoF boundary is shown. The merged DoF boundary may be calculated, for example, at the start of an XR application if the base constraints are static or change periodically (eg, at most every frame) for time-evolving or dynamically defined boundaries.

[0198] If the computation of the user's merged boundary fails (eg, if there is no common intersection volume between all base boundaries), the XR application may initiate a set of predefined boundary failure actions. The set of predefined boundary failure actions may be defined within the interaction framework.

[0199] For example, a boundary failure action can be to display an error message. A boundary failure action can modify one or several basic DoF boundaries to obtain a valid (e.g., non-empty) merged DoF boundary, for example: to notify the user to move or rearrange their real environment to expand / modify the available space constraints; to modify the pose or ignore the volume asset to modify / suppress its related DoF constraints; and / or to modify the DoF constraints related to the user's expressive capabilities. If there is still no valid merged DoF boundary in the case of boundary failure action modification, an error message can be displayed before stopping the application.

[0200] A user may have dedicated boundary failure actions. Dedicated boundary failure actions may be referenced within a user representation (e.g., avatar / camera) glTF extension by adding a boundaryFailedActions parameter. The boundaryFailedActions parameter may include a set of numbers (e.g., an array of integers). The set of numbers may correspond to the positions of actions defined in the action array of the interaction framework. "boundaryFailedActions": [1,3]

[0201] Controlling user movement relative to the merged DoF boundaries may be provided. The XR application may periodically (e.g., at most every frame) control the user's position to check whether the user is within the merged DoF boundaries.

[0202] The determination of whether a user is within the merged DoF boundary may be based on one or more user movements. If user movement (e.g., significant user movement) is detected, a boundary check may be performed (e.g., only performed). In an example, the XR application may rely on trajectory prediction calculations to determine in advance whether the user is about to reach the merged boundary.

[0203] Once the user reaches or nearly reaches the merged boundary, the XR application may initiate a set of boundary reaching actions (e.g., predefined boundary reaching actions). The set of boundary reaching actions may be defined within the interaction framework. The set of boundary reaching actions may include one or more of the following: a gradual transition to a black screen rendering; display of a warning message; a haptic vibration signal; or an audio signal.

[0204] Users can have dedicated boundary reaching actions. These actions can be referenced in the previous user representation / camera glTF extension by adding the boundaryReachedActions parameter. The boundaryReachedActions parameter can include a set of numbers (e.g., an array of integers). The set of numbers can correspond to the positions of the actions defined in the action array of the interaction framework, as follows:

[0205] "boundaryReachedActions":[0,2]

[0206] Although the features and elements are described above in specific combinations, it will be understood by those of ordinary skill in the art that each feature or element may be used alone or in any combination with other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (sent via a wired or wireless connection) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media (such as built-in hard disks and removable disks), magneto-optical media, and optical media (such as CD-ROM disks and digital versatile disks (DVDs)). A processor associated with software may be used to implement a radio frequency transceiver for a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. A device, comprising: A processor, the processor being configured to: determining a first base degree of freedom (DoF) boundary associated with the user, wherein the first base DoF boundary is determined based on at least one of pre-runtime information or runtime information; determining a second base DoF boundary associated with the user based at least on the pre-runtime information or the run-time information; determining a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary; as well as Conditional upon the success of the determination of the merged DoF boundary, determining to control movement of the user based on the merged boundary. 2 . The apparatus according to claim 1 , wherein under the condition that the determination of the merged DoF boundary is unsuccessful, the processor is further configured to modify the first basic DoF boundary or the second basic DoF boundary to obtain a modified DoF boundary.

3. The apparatus of claim 2, wherein the processor is further configured to: A new merged DoF boundary is determined based on the modified DoF boundary and the first basic DoF boundary or the second basic DoF boundary.

4. The apparatus of claim 3, wherein the processor is further configured to: The modified DoF boundary is determined by determining a volumetric asset that disregards one or more of the first base DoF boundary or the second base DoF boundary.

5. The apparatus of claim 3, wherein the processor is further configured to: The modified DoF boundary is determined by modifying a spatial constraint associated with the first basic DoF boundary or the second basic DoF boundary.

6. The apparatus of claim 5, wherein the processor is configured to modify the spatial constraint comprises: The processor is configured to prompt the user to modify the user's physical environment. 7 . The device of claim 1 , wherein, conditional upon the determination of the merged DoF boundary being unsuccessful, the processor is further configured to modify a virtual item within an XR environment associated with the user.

8. The device of claim 1 , wherein the processor is configured to determine a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary comprises: The processor is configured to: determining that a physical environment of the first basic DoF boundary is different from a physical environment of the second basic DoF boundary; as well as Based on the difference, it is determined that the first base DoF boundary is not allowed in the merged DoF boundary.

9. The device of claim 1 , wherein the processor is configured to determine a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary comprises: The processor is configured to: determining that a physical environment of the first basic DoF boundary is different from a physical environment of the second basic DoF boundary; as well as Based on the difference, the merged DoF boundary is determined based on a common intersection of the first basic DoF boundary and the second basic DoF boundary.

10. A method comprising: determining a first base degree of freedom (DoF) boundary associated with the user, wherein the first base DoF boundary is determined based on at least one of pre-runtime information or runtime information; determining a second base DoF boundary associated with the user based at least on the pre-runtime information or the run-time information; determining a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary; as well as Conditional upon the success of the determination of the merged DoF boundary, determining to control movement of the user based on the merged boundary.

11. The method of claim 10, wherein under the condition that the determination of the merged DoF boundary is unsuccessful, the method further comprises: The first basic DoF boundary or the second basic DoF boundary is modified to obtain a modified DoF boundary.

12. The method according to claim 11, wherein the method further comprises: A new merged DoF boundary is determined based on the modified DoF boundary and the first basic DoF boundary or the second basic DoF boundary.

13. The method according to claim 12, wherein the method further comprises: The modified DoF boundary is determined by determining a volumetric asset that disregards one or more of the first base DoF boundary or the second base DoF boundary.

14. The method according to claim 12, wherein the method further comprises: The modified DoF boundary is determined by modifying a spatial constraint associated with the first basic DoF boundary or the second basic DoF boundary.

15. The method of claim 14, wherein modifying the spatial constraint comprises: The user is prompted to modify the user's physical environment.

16. The method of claim 10, wherein under the condition that the determination of the merged DoF boundary is unsuccessful, the method further comprises: A virtual item within the XR environment associated with the user is modified.

17. The method of claim 10, wherein determining a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary comprises: determining that a physical environment of the first basic DoF boundary is different from a physical environment of the second basic DoF boundary; as well as Based on the difference, it is determined that the first base DoF boundary is not allowed in the merged DoF boundary.

18. The method of claim 10, wherein determining a merged DoF boundary based on the first basic DoF boundary and the second basic DoF boundary comprises: determining that a physical environment of the first basic DoF boundary is different from a physical environment of the second basic DoF boundary; as well as Based on the difference, the merged DoF boundary is determined based on a common intersection of the first basic DoF boundary and the second basic DoF boundary.

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