Video coding incorporating intra sub-partitions and template-based intra mode derivation techniques

Abstract

The coding block on which the ISP has been initiated may include a plurality of sub-partitions. For a first sub-partition in the coded block, an intra prediction mode may be derived based on template samples associated with the first sub-partition. The first sub-partition may be decoded based on the intra prediction mode. For a second sub-partition in the coded block, an intra prediction mode may be derived based on template samples associated with the second sub-partition, and the second sub-partition may be decoded based on the intra prediction mode. Sub-partitions in the coding block may independently derive intra prediction modes using decoder-side intra mode derivation and / or template-based intra mode derivation.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of European Provisional Patent Application 22306527.7 filed on October 11, 2022, the contents of which are incorporated herein by reference. Background Art

[0002] Video coding systems can be used to compress digital video signals, for example to reduce the storage and / or transmission bandwidth required for such signals. Video coding systems can include, for example, block-based, wavelet-based, and / or object-based systems. Summary of the invention

[0003] Template-based intra mode derivation (TIMD) and intra sub partition (ISP) processes can be combined to use reconstructed samples from ISP in TIMD. Systems, methods, and tools for performing TIMD processes for subpartitions of decoding blocks (e.g., transform units (TUs)) are disclosed. In various examples, when used with ISP, TIMD can be performed independently for each subpartition. The order of encoding / decoding can be determined based on the identified conditions, which can enable the use of more reference samples. In various examples, when the ISP subpartitions are thinner and / or smaller (e.g., subpartitions with a width or height of less than four), independent subpartition level TIMD derivation and / or encoding / decoding reordering can be used.

[0004] The ISP-enabled coding block may include multiple subpartitions. For a first subpartition in the coding block, a first intra prediction mode may be derived based on a template sample associated with the first subpartition. The first subpartition may be decoded based on the intra prediction mode. For a second subpartition in the coding block, a second intra prediction mode may be derived based on a template sample associated with the second subpartition, and the second subpartition may be decoded based on the second intra prediction mode. The intra prediction mode(s) for the subpartitions of the coding block may be independently derived using decoder-side intra mode derivation and / or template-based intra mode derivation.

[0005] For example, a prediction mode for a coding block may be derived based on a template sample of the coding block. A subpartition may be decoded based on an intra prediction mode derived based on a template sample of the coding block (e.g., at a block level) and an intra prediction mode derived based on a template sample of the subpartition (e.g., at a subpartition level).

[0006] For example, a video encoder may determine to use an ISP mode to encode a coding block. The coding block may include a plurality of subpartitions. For a first subpartition in the coding block, an intra-prediction mode may be derived based on a template sample associated with the first subpartition. The first subpartition may be encoded based on the intra-prediction mode. For a second subpartition in the coding block, an intra-prediction mode may be derived based on a template sample associated with the second subpartition, and the second subpartition may be encoded based on the intra-prediction mode.

[0007] For example, probable prediction modes may be obtained for a subpartition. Based on the probable prediction modes, the prediction of the template samples associated with the subpartition may be calculated, and a corresponding prediction error corresponding to the probable prediction mode may be calculated (e.g., based on the prediction of the template samples and a decoded reference sample of the template samples). For example, an intra-prediction mode may be selected from among the probable prediction modes based on the prediction error (e.g., in encoding and / or decoding the subpartition).

[0008] A video decoding device may be configured to obtain a coding block having a plurality of sub-partitions. The video decoding device may derive an intra-prediction mode for a sub-partition based on a template associated with the sub-partition (e.g., each sub-partition) (e.g., each sub-partition may have a template for deriving an intra-prediction mode). The decoding device may decode the sub-partition (e.g., each sub-partition) based on the derived intra-prediction mode for the sub-partition (e.g., as opposed to decoding based on an intra-prediction mode derived for the coding block).

[0009] The video decoding apparatus may reconstruct the first sub-partition, and a template for a second sub-partition (eg, a next ordered sub-partition) may be based on one or more reconstructed samples of the first sub-partition. For example, the template for the second sub-partition may include one or more reconstructed samples in the first sub-partition.

[0010] The video decoding device may obtain a plurality of possible prediction modes associated with the sub-partition. The video decoding device may determine a plurality of predictions of a template associated with the sub-partition based on the plurality of possible prediction modes associated with the sub-partition. The video decoding device may derive an intra-prediction mode, for example, based on the plurality of predictions of the template. The video decoding device may repeat this process for each sub-partition, such that the intra-prediction mode derived for each sub-partition is based on (e.g., based in part on) a plurality of predictions of the template associated with the respective sub-partition.

[0011] The video decoding apparatus may derive, for each sub-partition, a second intra prediction mode based on the template associated with the respective sub-partition and the plurality of predictions of the template associated with the respective sub-partition. The video decoding apparatus may decode each sub-partition based on the second intra prediction mode associated with the respective sub-partition.

[0012] In an example, a second prediction mode may be associated with the coding block.The video decoding apparatus may decode each sub-partition based on the intra prediction mode associated with the corresponding sub-partition and the second prediction mode associated with the coding block.

[0013] The video decoding apparatus may identify a plurality of candidate modes based on the first intra prediction mode, and may derive the second intra prediction mode from the plurality of candidate modes. For example, a TIMD search may be performed on a mode adjacent to the derived mode.

[0014] The video decoding apparatus may obtain, for example, a sub-partition (eg, each sub-partition), a plurality of prediction errors associated with a template associated with the sub-partition, and may derive an intra prediction mode for the sub-partition based on the plurality of prediction errors. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1A is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented.

[0016] Figure 1B is a diagram showing the embodiment of the invention. Figure 1A A system diagram of an example wireless transmit / receive unit (WTRU) for use within the illustrated communication system.

[0017] Figure 1C is a diagram showing the embodiment of the 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.

[0018] Figure 1D is a diagram showing the embodiment of the invention. Figure 1A System diagram of yet another example RAN and yet another example CN for use within the illustrated communication system.

[0019] Figure 2 An example video encoder is shown.

[0020] Figure 3 An example video decoder is shown.

[0021] Figure 4 Example systems are shown in which various aspects and examples may be implemented.

[0022] Figure 5A Example reference samples for intra prediction are shown.

[0023] Figure 5B An example sample replacement scenario for intra prediction is shown.

[0024] Figure 6 An example reference sample replacement for intra prediction is shown.

[0025] Fig. 7A , 7B 7C show example intra prediction directions for intra prediction modes.

[0026] Fig. 8A and 8B Example wide angle intra prediction is shown.

[0027] Fig. 9 An example comparison of wide-angle intra prediction mode and angular prediction mode is shown.

[0028] Fig.10 An example planar mode interpolation is shown.

[0029] Fig.11 An example inter prediction mode scenario using reconstructed reference samples is shown.

[0030] Fig. 12A , 12B and 12C show an example template-based intra mode derivation (TIMD) process.

[0031] Fig.13A and Fig. 13B Example sub-partitioning of coding units based on block size is shown.

[0032] Fig.14 An example sub-partitioning scenario using an И-scan order is shown.

[0033] Fig.15 An example scanning order for a reference sample scene is shown.

[0034] Fig.16A An example of transform unit scanning using a Z-scan order is shown.

[0035] Fig. 16B An example of transform unit scanning using a И scan order is shown.

[0036] Fig.17A , 17B 17C show examples of reordered intra subpartitioning (ISP) decoding. DETAILED DESCRIPTION

[0037] Figure 1A 1 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.

[0038] 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.

[0039] 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. While the base stations 114a, 114b are each depicted as a single element, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0040] The base station 114a may be part of the RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, etc. The base station 114a and / or the 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 licensed and unlicensed spectrums. A cell may provide coverage of wireless services to a specific geographic area, which may be relatively fixed or may change over time. The cell may be further divided into cell sectors. For example, a cell associated with the base station 114a may be divided into three sectors. Therefore, in one embodiment, the base station 114a may include three transceivers, i.e., one transceiver for each sector of the cell. In an embodiment, the 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.

[0041] 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).

[0042] 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).

[0043] 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) that may establish the air interface 116 using Long Term Evolution (LTE) and / or Advanced LTE (LTE-A) and / or Advanced LTE Pro (LTE-APro).

[0044] 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).

[0045] 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 used 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).

[0046] 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, CDMA2000EV-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.

[0047] 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 yet 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.

[0048] 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 advanced 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 advanced 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, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0049] The CN 106 / 115 may also serve 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 communication networks 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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 by 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, IR, UV or visible light signals. In another embodiment, the send / receive element 122 may be configured to send and / or receive both RF signals and optical signals. It should be understood that the send / receive element 122 may be configured to send and / or receive any combination of wireless signals.

[0054] Although the transmit / receive element 122 Figure 1B 1 as a single element, 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.

[0055] 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.

[0056] 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, and the like. In other embodiments, the processor 118 may access information from and store data in a memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0057] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control power to 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.

[0058] 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 its 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.

[0059] The processor 118 may also be 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.

[0060] The WTRU 102 may include a full-duplex radio for which transmission and reception of some or all 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 the processor 118). In an embodiment, the WRTU 102 may include a half-duplex radio for which transmission and reception of some or all 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.

[0061] 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.

[0062] 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.

[0063] 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 UL and / or DL, etc. Figure 1C As shown, the eNode-Bs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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 networks and / or wireless networks owned and / or operated by other service providers.

[0069] 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.

[0070] In a representative embodiment, the other network 112 may be a WLAN.

[0071] 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 carries traffic away from the BSS. Traffic originating from outside the BSS and leading to the STA may be reached by the AP and may be delivered to the STA. Traffic originating from the STA and leading 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, wherein 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. Point-to-point traffic may be transmitted between the source STA and the destination STA (e.g., directly between them) using a direct link establishment (DLS). 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 within or using the IBSS (eg, all STAs in the STA) may communicate directly with each other. The IBSS communication mode may sometimes be referred to herein as an "ad hoc" communication mode.

[0072] 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 listen to the primary channel. In the case where the primary channel is listened / detected and / or determined to be busy by a specific STA, the specific STA may back off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0073] 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.

[0074] 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).

[0075] 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).

[0076] 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 (supporting only a 1MHz operating mode) is sending to the AP, the entire available frequency band may be considered busy even if most of the frequency bands remain idle and may be available.

[0077] 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.

[0078] Figure 1D 1 is a system diagram showing the RAN 113 and the CN 115 according to 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.

[0079] 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, gNB 180a may transmit multiple component carriers to WTRU 102a (not shown). A subset of these component carriers may be on unlicensed spectrum, while the remaining component carriers may be on licensed spectrum. In an embodiment, gNBs 180a, 180b, 180c may implement coordinated multi-point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and / or gNB 180c).

[0080] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with parameter sets that may be scalable. 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 varying absolute time lengths over time).

[0081] 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 WTRUs 102a, 102b, 102c may communicate / connect with the gNB 180a, 180b, 180c while also communicating / connecting with another RAN, such as the eNode-B 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement the DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNode-B 160a, 160b, 160c may act as a mobility anchor for the WTRUs 102a, 102b, 102c, and the gNB 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0082] Each of the gNBs 180a, 180b, 180c 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 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.

[0083] 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.

[0084] 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, support of network slicing (e.g., handling of different PDU sessions with different requirements), selecting a specific SMF 183a, 183b, management of registration areas, termination of 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.

[0085] The SMF 183a, 183b may be connected to the AMF 182a, 182b in the CN 115 via the N11 interface. The SMF 183a, 183b may also be connected to the UPF 184a, 184b in the CN 115 via the N4 interface. 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 implementation and QoS, providing downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0086] 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.

[0087] 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 networks 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 an N3 interface to the UPF 184a, 184b and an N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0088] 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-d, base station 114a-b, evolved Node B 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF182a-b, UPF 184a-b, SMF 183a-b, DN 185a-b 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.

[0089] 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.

[0090] One or more simulation devices may 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 may 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 may be test devices. The simulation device may use direct RF coupling and / or wireless communication via RF circuits (e.g., which may include one or more antennas) to send and / or receive data.

[0091] 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 laboratory 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 may include one or more antennas) can be used by the simulation device to send and / or receive data.

[0092] The present application describes a number of aspects, including tools, features, examples, 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 to describe clearly 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.

[0093] The aspects described and contemplated in this application can be implemented in many different forms. Figures 5 to 17 described herein may provide some examples, but other examples are also contemplated. The discussion of Figures 5 to 17 does not limit the breadth of a specific implementation. 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 aspects and other aspects may be implemented as a method, an 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.

[0094] 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.

[0095] Various methods are described herein, and each 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 purpose of specific steps and / or actions can be modified or combined. In addition, in various examples, terms such as "first", "second" and the like can be used to modify elements, parts, steps, operations, etc., such as "first decoding" and "second decoding". Unless specifically required, the use of such terms does not imply the ordering of the modification 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 an overlapping time period of the second decoding.

[0096] like Figure 2 and Figure 3 As shown, various methods and other aspects described in this application can be used to modify modules (e.g., decoding modules) of video encoder 200 and decoder 300. In addition, the subject matter disclosed herein 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 extensions of any such standards and recommendations. Unless otherwise indicated or technically excluded, the aspects described in this application can be used alone or in combination.

[0097] Various values ​​are used in the examples described herein, such as number of bits, bit depth, etc. These and other specific values ​​are for purposes of describing the examples, and the aspects are not limited to these specific values.

[0098] In the context of video coding, an example intra subpartitioning (ISP) process may be combined with template-based intra mode derivation (TIMD).

[0099] Figure 2An example of a video encoder 200 (eg, a block-based hybrid video encoder) is shown. Variations of the example encoder 200 are contemplated, but for clarity, the encoder 200 is described below without describing all contemplated variations.

[0100] Before being encoded, the video sequence may undergo a pre-encoding process (201), for example by performing one or more of the following: 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, for example, to obtain a transmission profile that is resilient (e.g., more resilient) to compression (e.g., using histogram equalization of one of the color components). Metadata may be associated with the pre-processing and may be appended to the bitstream.

[0101] In encoder 200, as described below, a picture may be encoded (e.g., may be encoded by an encoder element). The picture to be encoded may be partitioned (202) and processed in units of, for example, CUs (coding units). Each unit may be encoded using, for example, intra mode or inter mode. When the unit is encoded in intra mode, intra prediction (260) may be performed. In inter mode, motion estimation (275) and motion compensation (270) may be performed. The encoder may determine (205) whether the CU will be encoded using intra mode or inter mode, and the intra / inter decision may be indicated (e.g., by the encoder), for example, by a prediction mode indicator (e.g., a prediction mode flag). For example, a prediction residual may be calculated by subtracting (210) the prediction block from the original image block. In an intra frame, the CU may be intra predicted (e.g., in an intra (I) frame), while in an inter frame, the CU may be intra predicted or inter predicted.

[0102] The prediction residual may be transformed at 225 and quantized at 230. At 245, one or more of the quantized transform coefficients, motion vectors, or other syntax elements (e.g., picture partition information) may be entropy coded to output a bitstream. The encoder may apply quantization directly to the untransformed residual transmission (e.g., skip the transform). The transform and quantization may be bypassed (e.g., bypassed by the encoder). For example, the residual may be coded (e.g., directly coded without applying the transform or quantization process).

[0103] The coded block may be decoded (e.g., by an encoder) to provide a reference (e.g., a reference for further prediction). The quantized transform coefficients may be dequantized at 240 and inverse transformed at 250 (e.g., inverse transformed to decode the prediction residual). At 255, the decoded prediction residual and the prediction block may be combined, and the image block may be reconstructed. An in-loop filter at 265 may be applied to the reconstructed image to perform, for example, deblocking / SAO (sample adaptive offset) / ALF (adaptive loop filter) filtering (e.g., to reduce coding artifacts). At 280, the filtered image may be stored in a reference picture buffer.

[0104] Figure 3 300. In the decoder 300, a bitstream may be decoded (eg, by decoder elements) as described herein. The video decoder 300 may perform the same operations as described herein. Figure 2 The decoding pass is the inverse of the encoding pass described in . As described herein, encoder 200 may perform video decoding as part of encoding video data.

[0105] Specifically, the input of the video decoder may include video data (e.g., a video bitstream), which may be generated by the video encoder 200. At 330, the bitstream may be entropy decoded (e.g., to obtain one or more transform coefficients, prediction modes, motion vectors, or other coding information). Picture partition information may indicate how the picture is partitioned. At 355, the decoder may partition the picture according to the decoded picture partition information. The transform coefficients may be dequantized at 340 and inversely transformed at 350 to decode the prediction residual. A prediction block may be obtained at 370 from the intra-frame prediction at 360 or the motion compensated prediction at 375 (e.g., inter-frame prediction). At 355, the decoded prediction residual and the prediction block may be combined, and the image block may be reconstructed. At 365, an in-loop filter may be applied to the reconstructed image. At 380, the filtered image may be stored in a reference picture buffer. The content of the reference picture buffer 380 on the decoder side may be the same as the content of the reference picture buffer 280 on the encoder 200 side (e.g., for the picture).

[0106] The decoded picture may further undergo post-decoding processing at 385, such as one or more of: inverse color transform (e.g., conversion from YcbCr 4:2:0 to RGB 4:4:4) or inverse remapping (e.g., performing the inverse of the remapping process performed in the pre-encoding process at 201). The post-decoding processing may use metadata derived in the pre-encoding process and may be signaled in the video data (e.g., a bitstream). In an example, the decoded image (e.g., after applying the in-loop filter 365 and / or after the post-decoding processing 385 if post-decoding processing is used) may be sent to a display device for presentation to a user.

[0107] Figure 4 4 is a schematic diagram showing an example of a system in which various aspects and examples described herein can be implemented. System 400 may be embodied as a device including various components described below and 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, connected home appliances, and servers. The elements of system 400 may be embodied in a single integrated circuit (IC), multiple ICs, and / or discrete components, either individually or in combination. For example, in at least one example, the processing and encoder / decoder elements of system 400 are distributed over multiple ICs and / or discrete components. In various examples, system 400 is communicatively coupled to one or more other systems or other electronic devices via, for example, a communication bus or through dedicated input ports and / or output ports. In various examples, system 400 is configured to implement one or more aspects of the aspects described in this document.

[0108] 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-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 non-limiting examples, 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.

[0109] 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.

[0110] 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 examples, 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 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, partially decoded video, bitstreams, matrices, variables, and / or intermediate or final results of processing equations, formulas, operations, and / or operation logic.

[0111] In some examples, memory inside the processor 410 and / or the encoder / decoder module 430 is used to store instructions and provide working memory for processing required during encoding or decoding. However, in other examples, 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 examples, the external non-volatile flash memory is used to store, for example, an operating system for a television. In at least one example, a fast external dynamic volatile memory (such as RAM) is used as working memory for video encoding and decoding operations.

[0112] 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.

[0113] In various examples, the input device of frame 445 has the corresponding input processing element associated as known in the art.For example, the RF part can be associated with the element suitable for the following: (i) select the required frequency (also referred to as selecting signal, or limiting the signal band to a band), (ii) down-convert the selected signal, (iii) again band-limit to a narrower band to select the signal band that (for example) can be called a channel in some examples, (iv) demodulate the signal through down-conversion and band-limited, (v) perform error correction, and / or (vi) demultiplex to select the required data packet stream. The RF part of various examples includes one or more elements for performing these functions, such as frequency selector, signal selector, band limiter, channel selector, filter, down-converter, demodulator, error corrector and demultiplexer. The RF part can include a tuner that performs various functions in these functions, including, for example, down-converting the received signal to a lower frequency (for example, intermediate frequency or near baseband frequency) or to baseband. In a set-top box example, the RF part and its associated input processing element receive the RF signal sent by wired (for example, cable) medium, and filter to the desired frequency band by filtering, down-conversion and again to perform frequency selection.Various examples 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 inserting element between existing elements, for example, inserting amplifier and analog-to-digital converter.In various examples, the RF part includes antenna.

[0114] 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 stream as needed for presentation on the output device.

[0115] The various components of system 400 may be disposed within an integrated housing. Within the integrated housing, the various components may be interconnected and transmit data between the components using a suitable connection arrangement 425 (e.g., an internal bus known in the art, including an inter-chip (I2C) bus, wiring, and a printed circuit board).

[0116] 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.

[0117] In various examples, 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 via a communication channel 460 and a communication interface 450 suitable for Wi-Fi communications. The communication channel 460 of these examples is typically connected to an access point or router that provides access to external networks, including the Internet, to allow streaming applications and other cross-top communications. Other examples provide streaming data to the system 400 using a set-top box that delivers data via an HDMI connection of an input box 445. Still other examples use an RF connection of an input box 445 to provide streaming data to the system 400. As described above, various examples provide data in a non-streaming manner. Additionally, various examples use wireless networks other than Wi-Fi, such as cellular networks or network.

[0118] The system 400 may provide output signals to various output devices, including a display 475, a speaker 485, and other peripherals 495. The display 475 of various examples includes, for example, one or more of a touch screen display, an organic light emitting diode (OLED) display, a curved display, and / or a foldable display. The display 475 may be used for a television, a tablet computer, a laptop, a cellular phone (mobile phone), or other devices. The display 475 may also be integrated with other components (e.g., as in a smart phone), or may be independent (e.g., an external monitor for a laptop computer). In various examples, other peripherals 495 include one or more of an independent digital video disc (or digital versatile disc) (DVD, for both terms), a disc player, a stereo system, and / or a lighting system. Various examples use one or more peripherals 495 that provide functions based on the output of the system 400. For example, a disc player performs the function of playing the output of the system 400.

[0119] In various examples, control signals are transmitted between the system 400 and the display 475, speaker 485, or other peripheral device 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, the output devices may be connected to the system 400 via a communication interface 450 using a communication channel 460. The display 475 and 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 examples, the display interface 470 includes a display driver, such as, for example, a timing controller (TCon) chip.

[0120] For example, if the RF portion of input 445 is part of a separate set-top box, the display 475 and speaker 485 may alternatively be separate from one or more of the other components. In various examples where the display 475 and speaker 485 are external components, the output signal may be provided via a dedicated output connection including, for example, an HDMI port, a USB port, or a COMP output.

[0121] These examples may be performed by computer software implemented by processor 410 or by hardware or by a combination of hardware and software. As a non-limiting example, these examples may be implemented by one or more integrated circuits. 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, an optical memory device, a magnetic memory device, a semiconductor-based memory device, a fixed memory, and / or a removable memory. 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 / or a processor based on a multi-core architecture.

[0122] Various implementations involve decoding. As used herein, "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 examples, such processes include one or more of the processes typically performed by a decoder, such as entropy decoding, inverse quantization, inverse transform, and differential decoding. In various examples, such processes also include or alternatively include, for example, processes performed by a decoder of various implementations described herein.

[0123] As another example, in one example, "decoding" refers only to entropy decoding, in another example, "decoding" refers only to differential decoding, and in another example, "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.

[0124] Various implementations involve encoding. In a manner similar to the discussion above about "decoding", "encoding" as used in this application may encompass, for example, all or part of a process performed on an input video sequence to produce an encoded bitstream. In various examples, such processes include one or more of the processes typically performed by an encoder, such as partitioning, differential encoding, transforms, quantization, and entropy encoding. In various examples, such processes also include or alternatively include processes performed by encoders of various implementations described in this application.

[0125] As another example, in one example, "encoding" refers only to entropy encoding, in another example, "encoding" refers only to differential encoding, and in another example, "encoding" refers to a combination of differential decoding and entropy encoding. Whether the phrase "encoding process" specifically refers to a subset of operations or broadly refers 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.

[0126] 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.

[0127] The specific implementations and aspects described herein can be implemented in, for example, methods or processes, devices, software programs, data streams or signals. Even if only discussed in the context of a single form of specific implementation (e.g., discussed only as a method), the specific implementation of the features discussed can also be implemented in other forms (e.g., devices or programs). The device can be implemented in, for example, appropriate hardware, software, and firmware. These methods can 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. The processor also includes a communication device, such as, for example, a computer, a mobile phone, a portable / personal digital assistant ("PDA"), and other devices that facilitate information communication between end users.

[0128] References to "one example" or "an example" or "one implementation" or "an implementation" and other variations thereof mean that a particular feature, structure, characteristic, etc. described in connection with the example is included in at least one example. Thus, the phrases "in one example" or "in an example" or "in one implementation" or "in an implementation" and any other variations appearing in various places throughout this application are not necessarily all referring to the same example.

[0129] Additionally, the present application can involve "determining" various pieces of information. Determining information can include, for example, one or more of estimating information, calculating information, predicting information, or retrieving information from a memory. Obtaining can include receiving, retrieving, constructing, generating, and / or determining.

[0130] Furthermore, the present application can refer to "accessing" various information. Accessing information can 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.

[0131] Additionally, the present application can involve "receiving" various information. Like "accessing," receiving is intended to be a broad term. Receiving information can include, for example, one or more of accessing information or retrieving information (e.g., from a memory). Furthermore, "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.

[0132] 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 only the second listed option (B), or 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 only the second listed option (B), or only the third listed option (C), or only the first listed option and the second listed option (A and B), or only the first listed option and the third listed option (A and C), or only the second listed option and the third listed option (B and C), or all three options (A and B and C). As will be apparent to one of ordinary skill in this and related arts, this can be extended to as many items as listed.

[0133] Moreover, as used herein, the term "signaling" refers to (among other things) indicating something to a corresponding decoder. Thus, in one example, the same parameters are used on both the encoder side and the decoder side. Thus, for example, the encoder may 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. Bit savings are achieved in various examples by avoiding sending any actual function. It should be understood that signaling can be implemented in a variety of ways. For example, in various examples, one or more syntax elements, flags, etc. are used to signal information to the corresponding decoder. Although the verb form of the term "signaling" is mentioned above, the term "signal" can (for example, can also) be used as a noun in this article.

[0134] It will be apparent to one of ordinary skill in the art that a specific implementation can generate a variety of signals formatted to carry information that can be stored or can be sent, for example. The information can include, for example, instructions for executing a method or data generated by one of the described specific implementations. For example, a signal can be formatted to carry a bit stream of the example. Such a signal can be formatted as, for example, an electromagnetic wave (e.g., using a radio frequency portion of a spectrum) or a baseband signal. Formatting can include, for example, encoding a data stream and modulating a carrier using the encoded data stream. The information carried by the signal can be, for example, analog or digital information. As is well known, the signal can be sent via a variety of different wired or wireless links. The signal can be stored on a processor-readable medium, or accessed or received from a processor-readable medium.

[0135] Many examples are described herein. The features of the examples can be provided individually or in any combination across various claim categories and types. In addition, the examples can include one or more of the features, devices or aspects described herein individually or in any combination across various claim categories and types. For example, the features described herein can include a bitstream or signal of information generated as described herein to be implemented. This information can allow a decoder to decode a bitstream, an encoder, a bitstream and / or a decoder according to any of the embodiments in the embodiments. For example, the features described herein can be implemented by creating and / or sending and / or receiving and / or decoding a bitstream or a signal. For example, the features described herein can be implemented by a method, a process, a device, a medium storing instructions, a medium storing data or a signal. For example, the features described herein can be implemented by TV, a set-top box, a mobile phone, a tablet computer or other electronic devices that perform decoding. TV, a set-top box, a mobile phone, a tablet computer or other electronic devices can display (for example, using a monitor, a screen or other type of display) a result image (for example, an image reconstructed from the residual of a video bitstream). TV, a set-top box, a mobile phone, a tablet computer or other electronic devices can receive a signal including a coded image and perform decoding.

[0136] These examples may be performed by a device having at least one processor. The device may be an encoder or a decoder. These examples may be performed by a computer program product stored on a non-transitory computer-readable medium and including program code instructions. These examples may be performed by a computer program including program code instructions. These examples may be performed by a bitstream including information representing a decoded block.

[0137] The intra prediction process may include reference sample generation, intra sample prediction, and / or post-processing of prediction samples. Intra sub-partitioning (ISP) may be used to encode and / or decode a coding block using a single intra prediction mode (e.g., in up to four transform units (TUs)). For example, ISP may enable the use of reconstructed samples of a TU for subsequent TUs. Template-based intra mode derivation (TIMD) may use adjacent reconstructed samples to determine the best intra prediction mode to use on a coding block. In an example, TIMD may use adjacent reconstructed samples (e.g., reconstructed samples of a template associated with a sub-partition) to derive the intra prediction mode of a sub-partition (e.g., a sub-partition that is sorted later). TIMD and ISP may be used in conjunction.

[0138] Figure 5A An example reference sample generation process is shown. Figure 5A In , the pixel value at coordinate (x, y) is indicated as P(x, y) relative to the current block starting at (0, 0). In the example, the reference sample ref[] may be referred to as L-shaped. For a size of N by N (in Figure 5A For an example prediction unit (PU) shown at P[0,0] in FIG, rows of 2N+2refIdx decoded samples may be formed from the top and right top pixels of the previously reconstructed PU. Columns of 2N+2refIdx samples may be formed from the reconstructed left and bottom left pixels of the PU. Figure 5A As illustrated in , in an example, the reference row and column of samples may be a number of samples (eg, a distance of refIdx) away from the example PU. An index "mrlIdx" may be signaled to indicate such a distance value.

[0139] In the intra prediction example, a corner pixel (e.g., at the top left position) can be used to fill the gap between references (e.g., top row and left column references). Reference sample replacement can be performed by copying the missing samples from the available samples (e.g., in a clockwise direction, counterclockwise direction, or a combination of both).

[0140] Figure 5B An example reference sample generation process is shown, where the top or left samples may not be available. Figure 5B In the example, the dashed area may correspond to a region of the picture that has not been reconstructed, and the dotted area may correspond to a missing reference. In an example, the sample may not be available because the corresponding CU may not be in the slice associated with the PU. In an example, a CU may be at a frame boundary (e.g., Figure 5B In an example, the CU may be in the lower right corner after a quadtree split (eg, as shown in FIG. 5 ). Figure 5B 510).

[0141] Figure 6 An example reference sample replacement 600 for intra prediction is shown. In an example, samples (e.g., top samples and / or left samples) may be available. At 610, a check may be performed to determine whether a reconstructed sample is available. If / when a sample is available, at 620, the sample may be copied to a reference sample buffer. If / when a sample is not available, at 630, repetition padding may be performed to fill the reference sample buffer. In an example, repetition padding may refer to reference sample replacement as discussed herein. At 640, intra sample prediction processing may be performed.

[0142] Intra-sample prediction may include predicting pixels of a target CU based on a reference sample set. Prediction modes may include planar and / or DC prediction modes (e.g., which may be used to predict smooth and gradually changing areas). Angular prediction modes (e.g., angles defined from 45 degrees to -135 degrees in a clockwise direction) may be used to capture different directional structures. For square blocks, directional prediction modes (e.g., 33 directional modes for square blocks) that may be indexed (e.g., from 2 to 34) may be used. The prediction modes may correspond to different prediction directions. Figures 7A-7C Example prediction directions are shown. The angular prediction modes may correspond to angular directions (e.g., 65 angular prediction modes may correspond to 33 angular directions), and the angular directions (e.g., another 32 angular directions) may correspond to intermediate directions between adjacent pairs, such as Figure 7B shown.

[0143] Fig. 7A Example intra prediction directions are shown. The numbers may represent the prediction mode index associated with the corresponding direction. Modes 2 to 17 may indicate horizontal prediction (H-26 to H+32), and modes 18 to 34 may indicate vertical prediction (V-32 to V+32). Figure 7B Intra prediction is shown (eg, for a square block). Modes less than 34 may indicate horizontal prediction. Modes greater than 34 may indicate vertical prediction. Figure 7C Available (eg, all available) intra prediction directions are shown. The dashed line may represent a wide angle intra prediction mode (WAIP). Figure 7B-7C The indices -1 to -14 shown in FIG. 7 may be remapped to be from 1 to -12 (e.g., so that the angular mode indices are consecutive). Modes 15 (e.g., remapped to -13) and 81 may not be present in FIG. 7 because the block size (e.g., block size is not allowed) may not use modes 15 (e.g., remapped to -13) and 81, but modes 15 (e.g., remapped to -13) and 81 may be processed by the reference code.

[0144] In an example, directional intra prediction may include a wide-angle intra prediction mode (eg, for non-square blocks). Figures 8A-8B Example non-square blocks (e.g., Fig. 8A shows a block that is wider than it is tall, while Figure 8B Blocks are shown that are taller than they are wide).

[0145] In the intra prediction example, the predictor samples on the reference array may be copied inside the target PU along the corresponding direction. The predictor samples may have locations (e.g., integral locations that may correspond to the associated reference sample locations). In an example, the predictor sample locations may have fractional parts (e.g., the predictor sample locations may correspond to two reference samples). In the fractional part example, the predictor samples may be interpolated using the nearest reference samples (e.g., which may involve post-processing of the prediction samples). For example, a linear interpolation of the two nearest reference samples may be performed to calculate the predictor sample values. For example, a 4-tap filter (e.g., fT[]) may be used to calculate the predictor sample values ​​(e.g., such a filter may be selected based on the intra mode direction).

[0146] Fig. 9 An example non-square block (e.g., a non-square block whose width is strictly greater than its height) is shown with the angle pattern replaced by the wide angle pattern. Fig. 9 As shown, wide angle intra prediction directions (eg, 67 and 68) may be used.

[0147] Table 1 below provides example indices of intra prediction modes replaced by wide mode. Table 1: Index of intra prediction modes replaced by wide mode Width / Height The replaced intra prediction mode index Added corner mode 2 2 to 7 67 to 72 4 2 to 11 67 to 76 8 2 to 13 67 to 78 16 2 to 15 67 to 80 32 2 to 16 67 to 81 1 none none 1 / 2 61 to 66 -4 to 1 1 / 4 57 to 66 -8 to 1 1 / 8 55 to 66 -10 to 1 1 / 16 53 to 66 -12 to 1 1 / 32 52 to 66 -13 to 1

[0148] In an example, the DC prediction mode may use the average of the samples of the L shape to fill the prediction. In some examples (eg, those featuring a non-square CU), the DC prediction mode may use the average of the reference samples of the longer side.

[0149] In an example, planar mode prediction may involve spatially interpolating reference samples. Fig.10 An example planar mode prediction is shown. The example prediction mode can be replaced with a reconstructed reference sample. Block prediction can be based on reconstructed reference samples located in neighboring templates. For example, a local illumination compensation (LIC) model can modify the inter-frame prediction samples with a linear model, such as: P'(x)=aP(x)+b[1]

[0150] P' may be a corrected prediction, P may be an inter prediction, x may be a sample position, and (a, b) may be illumination compensation parameters (eg, corresponding to a LIC model).

[0151] Fig.11An example scenario 1400 involving an inter prediction mode using reconstructed reference samples is shown. LIC model parameters may be derived using some reconstructed samples adjacent to a current block 1410 associated with co-located adjacent samples in a reference block 1435. In some examples, reconstructed reference samples may not be available (e.g., if additional conditions have access restrictions to some reconstructed samples 1420; such conditions may be based on reducing implementation complexity, e.g., limiting memory access, limiting pipeline operations per block for reconstruction, etc.). For example, a restriction condition may be to prevent access to reconstructed samples of an adjacent block coded intra-frame when reconstructing the current block in inter mode. In such an example, reference sample replacement such as repeat padding may be applied.

[0152] In an example, a template-based intra mode derivation (TIMD) may be performed to derive the prediction mode(s) for a coding block. For a given luminance, such as Figures 12A-12C CB 1230 shown in, can be applied (e.g., in a similar manner) at the encoder and decoder sides via intra-prediction mode derivation of TIMD. (e.g., each) intra-prediction mode in the MPM list of the luma CB (e.g., supplemented by a default mode) can be used to calculate a prediction of the template (100 and 1210) of the luma CB based on the decoded reference samples of the template (102). The SATD between the prediction of the luma CB and the template can be calculated. The intra-prediction mode (e.g., two intra-prediction modes) with the smallest SATD (e.g., the smallest SATD) can be selected as the TIMD mode (one or more). For example, by Fig. 9 The direction inserted between each solid arrow and the adjacent arrow in , the directional intra-frame prediction mode set (e.g., for TIMD) can be expanded (e.g., from 65 to 129). The possible intra-frame prediction mode set derived via TIMD can collect modes (e.g., 131 modes). One or more intra-frame prediction modes (e.g., two intra-frame prediction modes) can be retained from the first pass test involving the MPM list, and the one or more intra-frame prediction modes can be supplemented by a default mode. For each retained intra-frame prediction mode that is not PLANAR or DC, the closest extended directional intra-frame prediction mode (one or more) (e.g., the two closest extended directional intra-frame prediction modes) can be tested. The SATD (one or more) between the prediction calculated using the closest extended directional intra-frame prediction mode (one or more) and the template of the luma CB can be calculated. The intra-frame prediction mode (one or more) with the lowest (e.g., minimum) SATD can be selected as the TIMD mode (one or more).

[0153] The directional intra prediction mode set can be expanded from 65 to 129, and intra prediction mode replacement can be adopted. Table 2 below provides example replacement intra prediction mode indexes. Table 2: Index of intra prediction modes replaced by wide mode condition The replaced intra prediction mode index W / H==2 [|2,12|] W / H==4 [|2,20|] W / H==8 [|2,24|] W / H==16 [|2,28|] W / H==32 [|2,30|] W / H==1 none H / W==2 [|120,130|] H / W==4 [|112,130|] H / W==8 [|108,130|] H / W==16 [|104,130|] H / W==32 [|102,130|]

[0154] Figures 12A-12C An example template of the current brightness CB and the decoded reference samples of the template used in TIMD are shown. Fig. 12A The template of the luminance CB may not exceed the boundary of the current frame. The current W×H luminance CB 1230 may be surrounded by its fully available template, which is composed of the w on its left at 1200. t ×H part and the W×h above it at 1210 t During the TIMD derivation step, the intra prediction mode tested can be selected from the template's 1+2w t +2W+2h t +2H decoded reference samples set 1220 predict the template of the current brightness CB. If W≤8, w t can be equal to two (2); otherwise, w t can be equal to 4, if H≤8, h t can be equal to two (2); otherwise h t Can be equal to 4.

[0155] Fig. 12B and 12C An example is shown in which at least a portion of the template of the luminance CB may be outside the boundaries of the current frame. Fig. 12B In the example, the current W×H brightness CB 1230 can be surrounded by its template, and the W×h above it at 1201 t Partially available. During the TIMD derivation step, at 1220, the tested intra prediction mode can be selected from the template's 1+2W+2h t +2H decoded reference samples set 1220 predict the template of the current brightness CB. Fig. 12C In the example, the current W×H brightness CB 1230 can be surrounded by its template, where only the left side of w at 1200 t ×H part is available. During the TIMD derivation step, the intra prediction mode tested can be selected from the 1+2w of the template t The template for predicting the current brightness CB from the set 1220 of +2W+2H decoded reference samples.

[0156] An example intra sub-partitioning (ISP) mode is discussed. In an example, the ISP may vertically or horizontally partition a luma intra prediction block into two or four sub-partitions depending on the block size. For example, the minimum block size of the ISP may be 4×8 (or 8×4). If the block size is larger than 4×8 (or 8×4), the block may be partitioned into four sub-partitions. Fig.13A and13B An example of partitioning is shown. Fig.13A and 13B The example sub-partition shown in may have at least 16 samples.

[0157] In the ISP example, the dependence of the 1xN / 2xN sub-block prediction on the reconstructed values ​​of the previously decoded 1xN / 2xN sub-blocks of the coding block may not be possible. The minimum width of the prediction of the sub-block may be four samples. For example, an 8xN (N>4) coding block coded using ISP with vertical partitioning is partitioned into two prediction regions, each with four transforms of size 4xN and size 2xN. A 4xN coding block coded using ISP with vertical partitioning can be predicted using a full 4xN block; in some such examples, four transforms may be used, each of 1×N. ISP may support transform sizes of 1xN and 2xN. In the ISP example, transforms of 4xN regions may be performed in parallel. For example, if a 4xN prediction region contains four 1xN transforms, there may be no transform in the horizontal direction; the transform in the vertical direction may be performed as a single 4xN transform in the vertical direction. In an example involving a 4xN prediction region containing two 2xN transform blocks, transform operations on the two 2xN blocks in either direction (e.g., horizontally or vertically) may be performed in parallel. In an example, processing such smaller blocks may avoid delays compared to processing 4x4 conventionally coded intra blocks.

[0158] In an example, the reconstructed samples of the sub-partition may be obtained by adding a residual signal to the prediction signal. Such a residual signal may be generated by processes such as entropy decoding, inverse quantization, inverse transformation, etc. The reconstructed sample values ​​of the example sub-partition may be used to generate a prediction for the next sub-partition, and each sub-partition may be processed repeatedly. In an example, the first sub-partition to be processed may contain the upper left sample of the CU and may be processed downward (e.g., for horizontal partitioning) or to the right (e.g., for vertical partitioning). In an example, the reference samples used to generate the sub-partition prediction signal may be located on the left and upper sides. The sub-partitions may share intra modes.

[0159] The ISP may interact with other coding tools. The ISP may interact with one or more of the following: multiple reference lines (MRL), entropy coding coefficient group size, CBF coding, transform size limit(s), or MTS indication (eg, MTS flag).

[0160] ISP can interact with MRL. For example, if a block has an MRL index other than 0, then the ISP mode information may not be sent to the decoder (e.g., the ISP encoding mode may be inferred to be 0).

[0161] The ISP may interact with the entropy coding efficiency group size. For example, the size of the entropy coded coefficient subblock may be modified to have 16 samples. The subblock size may affect the blocks generated by the ISP (e.g., where one or more dimensions are less than four samples). In other examples, the coefficient groups may maintain 4×4 dimensions. Table 3 below provides example group sizes corresponding to example block sizes. Table 3: Entropy decoding coefficient group size Block size Coefficient group size 1×N,N≥16 1×16 N×1,N≥16 16×1 2×N,N≥8 2×8 N×2,N≥8 8×2 All other possible M×N situations 4×4

[0162] ISP may interact with CBF coding. In an example, at least one sub-partition may have a non-zero CBF (e.g., an example involving CBF coding). For example, if n is the number of sub-partitions and the first n-1 sub-partitions have produced zero CBFs, then the CBF of the nth sub-partition may be inferred to be 1.

[0163] ISP can interact with transform size restrictions. For example, ISP transforms with lengths greater than 16 points can use DCT-II.

[0164] The ISP may interact with an MTS indication (e.g., an MTS flag). For example, if the MTS CU flag is set to 0, it may not be sent to the decoder. In an example, the encoder may not perform RD tests for the various available transforms corresponding to the resulting sub-partitions. The transform selection for the ISP mode may be selected based on, for example, the intra mode, the processing order, and / or the block size used. In such an example, signaling may not be required. For illustration, let t H and t V Become the horizontal and vertical transforms selected for the w×h subpartition, respectively, where w is the width and h is the height. The transforms may be selected according to the following rules: if w=1 or h=1, then there is no horizontal or vertical transform, respectively; if w≥4 and w≤16, then t H =DST-VII, otherwise t H =DCT-II; if h≥4 and h≤16, then t V =DST-VII, otherwise t V =DCT-II.

[0165] In ISP mode, intra modes (e.g., all 67 intra modes) may be allowed. PDPC may be applied if the corresponding width and height are at least 4 samples long. In an example, reference sample filtering (e.g., reference smoothing) and conditions on intra interpolation filter selection may be avoided, and a cubic (DCT-IF) filter may be applied for fractional position interpolation in ISP mode.

[0166] TIMD and ISP can be used on the same coding block. For a first subpartition in a coding block, a first intra prediction mode can be derived based on a template sample associated with the first subpartition. The first subpartition can be decoded based on the intra prediction mode. For a second subpartition in a coding block, a second intra prediction mode can be derived based on a template sample associated with the second subpartition, and the second subpartition can be decoded based on the second intra prediction mode.

[0167] For example, a TIMD mode (timdMode and timdModeSecondary) may be derived for a first subpartition. The first subpartition may be predicted using timdMode (e.g., pu1) and using timdModeSecondary (e.g., pu2). The predictions pu1 and pu2 may be averaged (e.g., weighted average) to compute a prediction of the first subpartition. The first subpartition may be quantized and transformed to derive a reconstructed first subpartition. The second subpartition may be predicted based at least in part on reconstructed samples from the first subpartition.

[0168] For example, the video decoding device may reconstruct the first sub-partition, and the template for the second sub-partition (e.g., the next sequential sub-partition) may be based on one or more reconstructed samples of the first sub-partition. For example, the template for the second sub-partition may include one or more reconstructed samples in the first sub-partition.

[0169] In some examples, TIMD may be performed independently for ISP subpartitions in a coding block.For a subpartition, a TIMD process may be performed to determine an intra prediction mode for the subpartition based on a template associated with the subpartition.

[0170] For example, possible prediction modes may be obtained for a sub-partition. Based on the possible prediction modes, the prediction of template samples associated with the sub-partition may be calculated, and a corresponding prediction error corresponding to the possible prediction mode may be calculated (e.g., based on the prediction of template samples and decoded reference samples of the template samples). For example, an intra-prediction mode may be selected from among the possible prediction modes based on the prediction error (e.g., to encode and / or decode the sub-partition).

[0171] In an example, a secondary TIMD mode may be calculated independently for each sub-partition (e.g., for blending). For example, for each sub-partition, a second intra-prediction mode may be derived based on a template associated with the respective sub-partition and multiple predictions of the template associated with the respective sub-partition. Each sub-partition may be encoded and / or decoded based on the second intra-prediction mode associated with the respective sub-partition.

[0172] The corresponding decoding process may include one or more of the following: the mode (one or more) of the first sub-partition (e.g., timdMode and timdModeSecondary) may be derived from the TIMD on the first sub-partition (e.g., instead of the CU); timdMode and timdModeSecondary may be used to predict the first sub-partition (e.g., pu1 and pu2, respectively); pu1 and pu2 may be averaged (e.g., using a weighted average) to calculate the prediction of the first sub-partition; quantization and transform may be applied to the first sub-partition to derive a reconstructed first sub-partition; or for the second sub-partition, a TIMD mode may be selected and the process may be repeated. The second sub-partition prediction may be based on the reconstructed samples of the first sub-partition.

[0173] In an example, the secondary TIMD mode may be a mode derived by a TIMD search (e.g., a primary TIMD mode) for the entire block. Each sub-partition may be encoded and / or decoded based on an intra-prediction mode specifically derived for the corresponding sub-partition and a second prediction mode associated with the coded block. For example, a mode may be searched on the CU, and for each sub-partition, one (e.g., only one) mode may be searched. The corresponding decoding process may include one or more of the following: a TIMD mode on the CU may be determined (e.g., timdModeSecondary); a TIMD mode on the first sub-partition may be determined (e.g., timdMode); the first sub-partition (e.g., pu1 and pu2, respectively) may be predicted using timdMode and timdModeSecondary; the predictions pu1 and pu2 may be averaged (e.g., using a weighted average) to calculate a prediction of the first sub-partition; quantization and transform may be applied to the first sub-partition to derive a reconstructed first sub-partition; or for a second sub-partition, a TIMD mode may be selected, and the process may be repeated for the sub-partition. The second sub-partition prediction may be based on the reconstructed samples of the first sub-partition.

[0174] In some examples, a timdMode may be derived for the entire CU. For a sub-partition, a TIMD search may be performed on adjacent modes. For example, a TIMD search on a sub-partition may be performed on modes within + / -N of the TIMDMode of the previous sub-partition (e.g., where N=3).

[0175] In some examples, the wide angle (WA) to be used may not be selected from the size of the full CU. In such examples, the available modes in the combination may correspond to the available modes. In examples where the first mode and the secondary mode are not calculated for the same block size, the WA used may be based on the block size at which they are calculated. For example, where the first mode is derived for a sub-partition and the secondary mode is derived for the entire CU, the first mode may use the WA for the sub-partition size and the secondary mode may use the WA for the CU size.

[0176] It will be appreciated that in examples involving a combination of DIMD and ISP, the examples discussed herein may also be applied to decoder-side intra mode derivation (DIMD). For example, for a sub-partition, a DIMD process may be performed to determine the intra prediction mode of the sub-partition based on neighboring samples of the sub-partition. The reconstructed samples in the sub-partition may be used to derive the intra prediction mode of the next sub-partition in the coding block.

[0177] In some examples combining DIMD and ISP, a first plane pattern may be derived from a complete coding unit, and / or a subsequent weighted angular pattern may be derived from adjacent reconstructed samples from an ISP sub-partition. In some such examples, the DIMD process may be performed independently (e.g., for each sub-partition).

[0178] In an example, the coding order of intra-frame sub-partitions may be changed (eg, to allow for more availability of reference samples).

[0179] In some examples, quadtree (QT) partitioning can be used for ISP, and the decoding order can be changed from raster scan (e.g., Z scan) to I scan, for example, when reference samples from the left are more likely to be relevant. Fig.14 An example of using И scanning is shown, where when decoding partition 2, the lower left sample (eg Fig.14 1) may be available. For example, for the first TU of the current CU, when the IPM derived from the TIMD template of the first TU through TIMD is an angular mode with an index less than 18 (eg, equivalent to a full horizontal mode), the decoding order may be changed.

[0180] In an example, the decoding order of the ISP may depend on the intra-frame prediction mode derived by TIMD for the first TU of the current CU using the ISP and / or the availability of neighboring decoded reference samples for each remaining TU. Determining the decoding order of the current CU using both the ISP and TIMD may depend on the intra-frame prediction mode for the first TU of the current CU derived by TIMD and / or the availability of neighboring decoded reference samples for each remaining TU.

[0181] Fig.15An example (1500) is shown in which a luma CB is segmented into four luma TBs via ISP using quadtree (QT) segmentation within the luma channel of an intra slice (CTU size 128). An example luma CTB that is not located on any slice boundary may be segmented via QT. A first result luma CB may be segmented via QT to produce Fig.15 Given the four 32x32 luma CBs shown in FIG. 15 , all decoded reference samples located above and to the left of the luma CB of interest ( 1510 ) may be available given the partitioning of the first 32x32 luma CB.

[0182] 16(A) shows an example scenario where the ISP follows a Z scan (e.g., (1610), (1620), (1630), and (1640)), resulting in decoded reference samples around the luma TB (1620) being available for the TIMD derivation step and application of the derived prediction mode. The decoded reference samples around the luma TB (1630) are available for prediction during the TIMD derivation and application of the derived mode.

[0183] Fig. 16B An example scenario is shown in which the ISP follows an I scan (1610), (1620), (1630), resulting in decoded reference samples around the luma TB (1630) being available for the TIMD derivation step and the application of the derived mode for prediction (1630). The decoded reference samples around the luma TB (1620) are available for the TIMD derivation and the application of the derived mode for prediction (1620). In an example where the intra-frame prediction mode for the first luma TB derived via TIMD is vertically positive, the mode derived via TIMD for the luma TB (1620) and the luma TB (1630) may be vertically positive. In such an example, the availability of decoded reference samples located above each consecutive luma TB in the current luma CB may be maximized. In an example involving segmenting a luma CB via an ISP using a QT, if the intra-frame prediction mode for the first luma TB derived via TIMD is vertically positive and decoded reference samples located above (and to the right of) the current luma CB are available, the ISP may select a Z scan. In an example involving segmenting luma CBs via ISP using QT, if the intra prediction mode for the first luma TB derived via TIMD is horizontally positive and decoded reference samples located to the left (and bottom left) of the current luma CB are available, the ISP may choose to perform an I scan. In the example, the default ISP scan may be chosen.

[0184] In an example involving segmenting a luma CB using QT via ISP, if the intra prediction mode for the first luma TB derived via TIMD is one of the last (e.g., last eight) vertical positive modes and decoded reference samples located above (and to the upper right) of the current luma CB are available, the ISP may select Z-scan. In an example involving segmenting a luma CB using QT via ISP, if the intra prediction mode for the first luma TB derived via TIMD is one of the first horizontal positive modes and decoded reference samples located to the left (and to the lower left) of the current luma CB are available, the ISP may select I-scan.

[0185] In an example, an indicator may be included in the video data (eg, encoded in a bitstream) to indicate the scan order.

[0186] In an example, the top left partition (e.g., partition 0) may be coded last (e.g., to allow reference samples on the right or bottom side to be available). Intra modes that may not be available in some codings (e.g., from the right or from below) may be used. In such examples (e.g., including when QT partitioning is used with ISP), 360° may be used for intra prediction angles. In examples where the right side of the coding block is available, the top right reference samples may be used as reconstructed samples from the right side.

[0187] Fig.17A -C shows an example of reordering of ISP decoding (e.g., to allow more directional modes). In dark grey are accessible reference samples, allowing regular IPM in black. In light grey are reference samples available from the new decoding order, allowing new directional angles to be depicted in light grey.

[0188] In an example, the decoding order may be modified to DIMD (eg, to use additional modes).

[0189] In various examples, the combination of ISP and TIMD can be applied when the ISP sub-partition is large enough to enable TIMD to be used normally. For example, when the decoding unit size has a width and height greater than, for example, 8, the ISP-TIMD combination can be enabled. In some examples, the combination can be enabled when the partition is horizontal and the width is greater than, for example, 8. In some examples, the sub-partition size can be directly tested to ensure that both the width and height are greater than, for example, 4.

[0190] In an example, the TIMD process can adapt to the smaller block size introduced by ISP sub-partitioning (e.g., to allow TIMD to be used on each sub-partition regardless of size). In an example, when the width of the sub-partition is, for example, 2 or 1, the TIMD process can use (e.g., can only use) the left template for SAD estimation for each mode.

[0191] In some examples, if the width of the sub-partition is 2 or 1, the left template width may be set to 1. In some examples, if the width of the sub-partition is 2 or 1, only vertical modes may be considered, such as using an upper reference sample. In an example, the limits may vary depending on whether the width and / or height of the sub-partition is 1 or 2.

Claims

1. A video decoding method, comprising: Obtaining a decoding block including a plurality of sub-partitions; For a first subpartition of the plurality of subpartitions, deriving a first intra prediction mode based on a first template associated with the first subpartition; Decoding the first sub-partition based on the first intra prediction mode; For a second subpartition of the plurality of subpartitions, deriving a second intra prediction mode based on a second template associated with the second subpartition; as well as The second sub-partition is decoded based on the second intra prediction mode.

2. The method according to claim 1, further comprising: The first sub-partition is reconstructed, wherein the second template associated with the second sub-partition includes at least one reconstructed sample in the first sub-partition.

3. The method according to claim 1, further comprising: obtaining a plurality of possible prediction modes associated with the first subpartition; as well as determining a plurality of predictions of the first template associated with the first subpartition based on the plurality of possible prediction modes associated with the first subpartition, wherein deriving the first intra prediction mode is further based on the plurality of predictions of the first template; obtaining a plurality of possible prediction modes associated with the second sub-partition; and Based on the plurality of possible prediction modes associated with the second subpartition, a plurality of predictions of the second template associated with the second subpartition is determined, wherein deriving the second intra prediction mode is further based on the plurality of predictions of the second template.

4. The method according to claim 3, further comprising: deriving, for the first subpartition, a secondary first intra prediction mode based on the first template associated with the first subpartition and the plurality of predictions of the first template, wherein decoding the first subpartition is further based on the secondary first intra prediction mode; as well as For the second subpartition, a secondary second intra prediction mode is derived based on the second template associated with the second subpartition and the plurality of predictions of the second template, wherein decoding the second subpartition is further based on the secondary second intra prediction mode.

5. The method according to claim 1, further comprising: A secondary prediction mode associated with the coding block is obtained, wherein decoding the first sub-partition is further based on the secondary prediction mode, and wherein decoding the second sub-partition is further based on the secondary prediction mode.

6. The method according to claim 1, further comprising: Obtaining a plurality of possible prediction modes associated with the decoding block; determining a plurality of predictions for the coding block based on the plurality of possible prediction modes associated with the coding block; deriving, for the first sub-partition, a secondary first intra prediction mode based on the plurality of predictions of the coding block, wherein decoding the first sub-partition is further based on the secondary first prediction mode; as well as For the second sub-partition, a secondary second intra prediction mode is derived based on the multiple predictions of the coding block, wherein decoding the second sub-partition is further based on the secondary second prediction mode.

7. The method according to claim 1, further comprising: Based on the first intra prediction mode, a plurality of candidate modes are identified, wherein the second intra prediction mode is derived from the plurality of candidate modes.

8. The method according to claim 1, further comprising: obtaining a plurality of prediction errors associated with the first template, the first template being associated with the first subpartition, wherein deriving the first intra prediction mode is based on the plurality of prediction errors associated with the first template; as well as A plurality of prediction errors associated with the second template is obtained, the second template being associated with the second subpartition, wherein deriving the second intra prediction mode is based on the plurality of prediction errors associated with the second template.

9. A video encoding method, comprising: Obtaining a decoding block including a plurality of sub-partitions; For a first subpartition, deriving a first intra prediction mode based on a first template associated with the first subpartition; encoding the first sub-partition based on the first intra prediction mode; For a second subpartition, deriving a second intra prediction mode based on a second template associated with the second subpartition; as well as The second sub-partition is encoded based on the second intra prediction mode.

10. The method according to claim 9, further comprising: The first sub-partition is reconstructed, wherein the second template includes at least one sample in the reconstructed first sub-partition.

11. The method according to claim 9, further comprising: obtaining a plurality of possible prediction modes associated with the first subpartition; as well as determining a plurality of predictions of the first template associated with the first subpartition based on the plurality of possible prediction modes associated with the first subpartition, wherein deriving the first intra prediction mode is further based on the plurality of predictions of the first template; obtaining a plurality of possible prediction modes associated with the second sub-partition; and Based on the plurality of possible prediction modes associated with the second subpartition, a plurality of predictions of the second template associated with the second subpartition is determined, wherein deriving the second intra prediction mode is further based on the plurality of predictions of the second template.

12. The method according to claim 11, further comprising: deriving, for the first subpartition, a secondary first intra prediction mode based on the first template associated with the first subpartition and the plurality of predictions of the first template, wherein encoding the first subpartition is further based on the secondary first intra prediction mode; as well as For the second sub-partition, a secondary second intra prediction mode is derived based on the second template associated with the second sub-partition and the plurality of predictions of the second template, wherein the second sub-partition is further based on the secondary second intra prediction mode.

13. The method according to claim 9, further comprising: A secondary prediction mode associated with the coding block is obtained, wherein encoding the first sub-partition is further based on the secondary prediction mode, and wherein encoding the second sub-partition is further based on the secondary prediction mode.

14. The method according to claim 9, further comprising: Obtaining a plurality of possible prediction modes associated with the decoding block; determining a plurality of predictions for the coding block based on the plurality of possible prediction modes associated with the coding block; deriving, for the first sub-partition, a secondary first intra prediction mode based on the plurality of predictions of the coding block, wherein encoding the first sub-partition is further based on the secondary first prediction mode; as well as For the second sub-partition, a secondary second intra prediction mode is derived based on the multiple predictions of the coding block, wherein encoding the second sub-partition is further based on the secondary second prediction mode.

15. The method according to claim 9, further comprising: obtaining a plurality of prediction errors associated with the first template, wherein deriving the first intra prediction mode is based on the plurality of prediction errors associated with the first template; as well as A plurality of prediction errors associated with the second template is obtained, wherein deriving the second intra prediction mode is based on the plurality of prediction errors associated with the second template.

16. A video decoding device, comprising: A processor configured to: Obtaining a decoding block including a plurality of sub-partitions; deriving, for a first subpartition of the plurality of subpartitions, a first intra prediction mode based on a first template associated with the first subpartition; decoding the first subpartition based on the first intra prediction mode; deriving, for a second subpartition of the plurality of subpartitions, a second intra prediction mode based on a second template associated with the second subpartition; as well as The second sub-partition is decoded based on the second intra prediction mode.

17. The video decoding device according to claim 16, wherein the processor is further configured to: The first sub-partition is reconstructed, wherein the second template associated with the second sub-partition includes at least one reconstructed sample in the first sub-partition.

18. The video decoding device according to claim 16, wherein the processor is further configured to: obtaining a plurality of possible prediction modes associated with the first subpartition; and determining a plurality of predictions of the first template associated with the first subpartition based on the plurality of possible prediction modes associated with the first subpartition, wherein deriving the first intra prediction mode is further based on the plurality of predictions of the first template; obtaining a plurality of possible prediction modes associated with the second sub-partition; and Based on the plurality of possible prediction modes associated with the second subpartition, a plurality of predictions of the second template associated with the second subpartition is determined, wherein deriving the second intra prediction mode is further based on the plurality of predictions of the second template.

19. The video decoding device according to claim 18, wherein the processor is further configured to: deriving, for the first subpartition, a secondary first intra prediction mode based on the first template associated with the first subpartition and the plurality of predictions of the first template, wherein decoding the first subpartition is further based on the secondary first intra prediction mode; and For the second sub-partition, a secondary second intra prediction mode is derived based on the second template associated with the second sub-partition and the plurality of predictions of the second template, wherein the second sub-partition is further based on the secondary second intra prediction mode.

20. The video decoding device of claim 16, wherein the processor is further configured to: A secondary prediction mode associated with the coding block is obtained, wherein decoding the first sub-partition is further based on the secondary prediction mode, and wherein decoding the second sub-partition is further based on the secondary prediction mode.

21. The video decoding device of claim 16, wherein the processor is further configured to: Obtaining a plurality of possible prediction modes associated with the decoding block; determining a plurality of predictions for the coding block based on the plurality of possible prediction modes associated with the coding block; deriving, for the first sub-partition, a secondary first intra prediction mode based on the plurality of predictions of the coding block, wherein decoding the first sub-partition is further based on the secondary first prediction mode; as well as For the second sub-partition, a secondary second intra prediction mode is derived based on the multiple predictions of the coding block, wherein decoding the second sub-partition is further based on the secondary second prediction mode.

22. The video decoding device of claim 16, wherein the processor is further configured to: Based on the first intra prediction mode, a plurality of candidate modes are identified, wherein the second intra prediction mode is derived from the plurality of candidate modes.

23. The video decoding device of claim 16, wherein the processor is further configured to: obtaining a plurality of prediction errors associated with the first template, the first template being associated with the first subpartition, wherein deriving the first intra prediction mode is based on the plurality of prediction errors associated with the first template; and A plurality of prediction errors associated with the second template is obtained, the second template being associated with the second subpartition, wherein deriving the second intra prediction mode is based on the plurality of prediction errors associated with the second template.

24. A video encoding device, comprising: A processor configured to: Obtaining a decoding block including a plurality of sub-partitions; For a first subpartition of the plurality of subpartitions, deriving a first intra prediction mode based on a first template associated with the first subpartition; encoding the first sub-partition based on the first intra prediction mode; For a second subpartition of the plurality of subpartitions, deriving a second intra prediction mode based on a second template associated with the second subpartition; as well as Based on the second intra prediction mode, the second sub-partition is encoded.

25. The video encoding device of claim 24, wherein the processor is further configured to: The first sub-partition is reconstructed, wherein the second template associated with the second sub-partition includes at least one reconstructed sample in the first sub-partition.

26. The video encoding device of claim 24, wherein the processor is further configured to: obtaining a plurality of possible prediction modes associated with the first subpartition; and determining a plurality of predictions of the first template associated with the first subpartition based on the plurality of possible prediction modes associated with the first subpartition, wherein deriving the first intra prediction mode is further based on the plurality of predictions of the first template; obtaining a plurality of possible prediction modes associated with the second sub-partition; and Based on the plurality of possible prediction modes associated with the second subpartition, a plurality of predictions of the second template associated with the second subpartition is determined, wherein deriving the second intra prediction mode is further based on the plurality of predictions of the second template.

27. The video encoding device of claim 26, wherein the processor is further configured to: deriving, for the first subpartition, a secondary first intra prediction mode based on the first template associated with the first subpartition and the plurality of predictions of the first template, wherein encoding the first subpartition is further based on the secondary first intra prediction mode; and For the second sub-partition, a secondary second intra prediction mode is derived based on the second template associated with the second sub-partition and the plurality of predictions of the second template, wherein the second sub-partition is further based on the secondary second intra prediction mode.

28. The video encoding device of claim 24, wherein the processor is further configured to: A secondary prediction mode associated with the coding block is obtained, wherein encoding the first sub-partition is further based on the secondary prediction mode, and wherein encoding the second sub-partition is further based on the secondary prediction mode.

29. The video encoding device of claim 24, wherein the processor is further configured to: Obtaining a plurality of possible prediction modes associated with the decoding block; determining a plurality of predictions for the coding block based on the plurality of possible prediction modes associated with the coding block; deriving, for the first sub-partition, a secondary first intra prediction mode based on the plurality of predictions of the coding block, wherein encoding the first sub-partition is further based on the secondary first prediction mode; as well as For the second sub-partition, a secondary second intra prediction mode is derived based on the multiple predictions of the coding block, wherein encoding the second sub-partition is further based on the secondary second prediction mode.

30. The video encoding device of claim 24, wherein the processor is further configured to: Based on the first intra prediction mode, a plurality of candidate modes are identified, wherein the second intra prediction mode is derived from the plurality of candidate modes.

31. The video encoding device of claim 24, wherein the processor is further configured to: obtaining a plurality of prediction errors associated with the first template, the first template being associated with the first subpartition, wherein deriving the first intra prediction mode is based on the plurality of prediction errors associated with the first template; and A plurality of prediction errors associated with the second template is obtained, the second template being associated with the second subpartition, wherein deriving the second intra prediction mode is based on the plurality of prediction errors associated with the second template.

32. Video data comprising information representing a coded first sub-partition and a coded second sub-partition generated according to any of the methods of any of claims 9 to 15.

33. A computer program product stored on a non-transitory computer readable medium and comprising program code instructions for implementing the steps of the method according to any one of claims 1 to 8 when executed by a processor.

34. A computer program comprising program code instructions for implementing the steps of the method according to any one of claims 1 to 8 when the program code instructions are executed by a processor.

Images