Template-based intra mode derivation with wide-angle intra prediction

Abstract

Systems, methods, and instrumentalities are disclosed for performing video coding to derive an intra prediction mode for predicting a current block using TIMD by wide angle intra prediction (WAIP). A most probable mode (MPM) list associated with a current block may be obtained. A test list of intra prediction modes may be determined from the MPM list. A first intra prediction mode may be tested, and may be excluded from the test list or not allowed to be tested due to the WAIP replacement. A prediction for the current block may be generated based on the tested intra prediction mode. The prediction may be used to decode the current block.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of European Provisional Patent Application No. 22305511.2 filed on April 8, 2022, the contents of which are hereby incorporated herein by reference. Background Art

[0003] Video coding systems may be used to compress digital video signals, for example, to reduce the storage and / or transmission bandwidth required for such signals. Video coding systems may include, for example, block-based, wavelet-based, and / or object-based systems. Summary of the invention

[0004] The present invention discloses systems, methods and means for performing video decoding to derive an intra-prediction mode for predicting a current block using template-based intra-mode derivation (TIMD) with wide-angle intra-prediction (WAIP). A most probable mode (MPM) list associated with the current block may be obtained. A test list of intra-prediction modes may be determined from the MPM list. A first intra-prediction mode may be tested, and the first intra-prediction mode may be excluded from the test list or not allowed to be tested due to wide-angle intra-prediction (WAIP) substitution. A prediction for the current block may be generated based on the tested intra-prediction mode. The prediction may be used to process (e.g., encode and / or decode) the current block.

[0005] A second intra-prediction mode may be tested and the second intra-prediction mode may be included in the test list. The prediction for the current block may be generated based on the tested first intra-prediction mode and the tested second intra-prediction mode test. The testing of the first intra-prediction mode may occur before the determining of the test list. The current block may be associated with a first shape, and the first intra-prediction mode may be associated with a second shape.

[0006] The first shape may be a rectangle, and the second shape may be a square. The lengths of adjacent sides of the first shape may be different from each other. The first shape may be a square, and the second shape may be a rectangle. The lengths of adjacent sides of the second shape may be different from each other.

[0007] A plurality of intra prediction mode indexes may be generated, and a prediction for a current block may be generated using the plurality of intra prediction mode indexes.

[0008] Weights of the plurality of intra prediction mode indexes may be calculated, and at least one of the weights may be a sum of absolute transformed differences (SATD). A prediction for the current block may be generated based on a subset of intra prediction mode indexes having a minimum predicted SATD from the plurality of intra prediction mode indexes.

[0009] The generated prediction may be further based on the calculated weights. The calculated weights may include a first calculated weight associated with the tested first intra-frame prediction mode and a second weight associated with the tested second intra-frame prediction mode. At least one decoded reference sample may be added for the first intra-frame prediction mode.

[0010] The systems, methods, and means described herein may relate to decoders. In some examples, the systems, methods, and means described herein may relate to encoders. In some examples, the systems, methods, and means described herein may relate to signals (e.g., signals from encoders and / or received by decoders). A computer-readable medium may include instructions for causing one or more processors to perform the methods described herein. A computer program product may include instructions that, when executed by one or more processors, cause one or more processors to perform the methods described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1A is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented.

[0012] Figure 1B is an example of a method that can be used according to an embodiment of the present invention. Figure 1A A system diagram of an example wireless transmit / receive unit (WTRU) for use within the illustrated communication system.

[0013] Figure 1C is an example of a method that can be used according to an embodiment of the present invention. Figure 1A System diagram of an example Radio Access Network (RAN) and an example Core Network (CN) for use within the illustrated communication system.

[0014] Figure 1D is an example of a method that can be used according to an embodiment of the present invention. Figure 1A System diagram of yet another example RAN and yet another example CN for use within the illustrated communication system.

[0015] Figure 2 An example video encoder is illustrated.

[0016] Figure 3 An example video decoder is illustrated.

[0017] Figure 4 Examples of systems in which various aspects and examples may be implemented are illustrated.

[0018] Figure 5 Examples of intra prediction modes in video coding toolsets, such as Versatile Video Coding (VVC) and Enhanced Compression Model (ECM), are illustrated.

[0019] Fig. 6A and Figure 6BAn example derivation of a Most Probable Mode (MPM) list for a current luma coding block (CB) belonging to an intra slice in an ECM is illustrated.

[0020] Fig. 7A and Figure 7B An example of signaling the intra prediction mode selected to predict the current luma CB in the ECM is illustrated.

[0021] Figure 8 An example of signaling the intra prediction mode selected to predict the current chroma CB pair in an ECM is illustrated.

[0022] FIG. 9A to FIG. 9B An example relationship between the range of a set of decoded reference samples around a current W×H block to be predicted and the range of allowed intra prediction angles is illustrated.

[0023] Fig.10 An example of an angular mode replaced by a wide angle mode for a non-square block having a width greater than a height is illustrated.

[0024] FIG. 11A to FIG. 11C An example of a template of the current luma CB and decoded reference samples of the template is illustrated.

[0025] FIG. 12A to FIG. 12B Examples of a directional range added by wide angle intra prediction (WAIP) and a directional range replaced by WAIP are illustrated.

[0026] Fig.13 An example of a direction range added by WAIP and a direction range replaced by WAIP when a reference sample of a current block is a square is illustrated.

[0027] Fig.14 An example of a direction range added by WAIP and a direction range replaced by WAIP when the reference sample of the current block is rectangular is illustrated.

[0028] Fig.15 An example of a Template Based Intra Mode Derivation (TIMD) derivation process for a current block to be predicted when one or more additional directional intra prediction modes are allowed is illustrated.

[0029] Fig.16 An example of a TIMD derivation process for a current block to be predicted, for example when one or more additional directional intra prediction modes are allowed, is illustrated.

[0030] Fig.17 An example of a TIMD derivation process for a current block to be predicted, for example when one or more additional directional intra prediction modes are allowed, is illustrated.

[0031] 18A to 18CAn example of adding decoded reference samples during TIMD derivation and prediction via TIMD for a rectangular W×H block to be predicted (W>H), for example when one or more directional intra prediction modes replaced by WAIP are allowed, is illustrated.

[0032] FIG. 19A to FIG. 19C An example of adding decoded reference samples during TIMD derivation and prediction via TIMD for a rectangular W×H block to be predicted (H>W), for example when one or more directional intra prediction modes replaced by WAIP are allowed, is illustrated.

[0033] FIG. 20A to FIG. 20C An example of adding decoded reference samples during TIMD derivation and prediction via TIMD for a rectangular W×H block to be predicted (W>H), for example when one or more directional intra prediction modes replaced by WAIP are allowed, is illustrated.

[0034] FIG. 21A to FIG. 21C An example of adding decoded reference samples during TIMD derivation and prediction via TIMD for a rectangular W×H block to be predicted (H>W), for example when one or more directional intra prediction modes replaced by WAIP are allowed, is illustrated.

[0035] FIG. 22A to FIG. 22C An example of adding decoded reference samples during TIMD derivation and prediction via TIMD for a square W×W block to be predicted is illustrated.

[0036] FIG. 23A to FIG. 23C An example of adding decoded reference samples during TIMD derivation and prediction via TIMD for a rectangular W×W block to be predicted is illustrated. DETAILED DESCRIPTION

[0037] A more detailed understanding may be obtained from the following description given by way of example in conjunction with the accompanying drawings.

[0038] Figure 1A1 is a diagram illustrating an example communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multiple access system that provides content such as voice, data, video, messaging, broadcast, etc. to multiple wireless users. The communication system 100 may enable multiple wireless users to access such content through sharing of system resources (including wireless bandwidth). For example, the communication system 100 may employ one or more channel access methods such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), zero tail unique word DFT spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multi-carrier (FBMC), etc.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] 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).

[0043] 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).

[0044] 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).

[0045] 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).

[0046] 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).

[0047] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi)), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), etc.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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).

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] In a representative embodiment, the other network 112 may be a WLAN.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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).

[0076] 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).

[0077] 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.

[0078] 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.

[0079] Figure 1D 1 is a system diagram illustrating the RAN 113 and the CN 115 in accordance with an embodiment. As noted above, the RAN 113 may employ NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 113 may also be in communication with the CN 115.

[0080] 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).

[0081] 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 Transmission Time Intervals (TTIs) of varying or scalable lengths (e.g., containing varying numbers of OFDM symbols and / or varying absolute time lengths over time).

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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 enforcement and QoS, providing downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0087] 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.

[0088] 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 the N3 interface to the UPF 184a, 184b and the N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0089] 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 emulate 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.

[0090] 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.

[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 circuitry (e.g., which can 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. Figure 5 to Figure 2 3 may provide some examples, but other examples are also contemplated. Figure 5 to Figure 2 3 does not limit the breadth of the specific implementations. At least one of these aspects generally relates to video encoding and decoding, and at least one other aspect generally relates to sending a generated or encoded bitstream. These and other aspects can be implemented as methods, apparatus, a computer-readable storage medium having stored thereon instructions for encoding or decoding video data according to any of the methods, and / or a computer-readable storage medium having stored thereon a bitstream generated according to any of the methods.

[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 the number of intra prediction modes, the number of most probable modes (MPMs), additional intra prediction modes, block size dimensions, ratios of block height to block width, block shapes, prediction mode indexes, wide angle intra prediction (WAIP) modes, angular degrees, angular mode ranges, etc. These and other specific values ​​are for purposes of describing the examples, and the described aspects are not limited to these specific values.

[0098] Figure 2 is a diagram illustrating an example video encoder. Variations of the example encoder 200 are contemplated, but the following describes encoder 200 for clarity without describing all contemplated variations.

[0099] Before being encoded, the video sequence may undergo a pre-encoding process (201), for example, applying a color transform to an input color picture (e.g., conversion from RGB 4:4:4 to YCbCr 4:2:0), or performing a remapping of input picture components to obtain a signal distribution that is more resilient to compression (e.g., using histogram equalization of one of the color components). Metadata may be associated with the pre-processing and appended to the bitstream.

[0100] In encoder 200, a picture is encoded by encoder elements as described below. The picture to be encoded is partitioned (202) and processed in units such as coding units (CUs). Each unit is encoded, for example, using intra mode or inter mode. When a unit is encoded in intra mode, the unit performs intra prediction (260). In inter mode, motion estimation (275) and compensation (270) are performed. The encoder decides (205) which of intra mode or inter mode to use to encode the unit, and indicates the intra / inter decision by, for example, a prediction mode flag. The prediction residual is calculated, for example, by subtracting (210) the predicted block from the original image block.

[0101] The prediction residual is then transformed (225) and quantized (230). The quantized transform coefficients, along with motion vectors and other syntax elements (such as picture partition information), are entropy coded (245) to output a bitstream. The encoder may skip the transform and apply quantization directly to the untransformed residual signal. The encoder may bypass both the transform and quantization, i.e., directly code the residual without applying the transform or quantization process.

[0102] The encoder decodes the coded block to provide a reference for further prediction. The quantized transform coefficients are dequantized (240) and inverse transformed (250) to decode the prediction residual. The image block is reconstructed by combining the decoded prediction residual and the predicted block (255). An in-loop filter (265) is applied to the reconstructed picture to perform, for example, deblocking / SAO (sample adaptive offset) / ALF (adaptive loop filter) filtering to reduce coding artifacts. The filtered image is stored in a reference picture buffer (280).

[0103] Figure 3 is a diagram illustrating an example of a video decoder. In the example decoder 300, a bitstream is decoded by decoder elements as described below. The video decoder 300 generally performs the same Figure 2 The decoding process is the reverse of the encoding process described in . The encoder 200 also typically performs video decoding as part of encoding the video data.

[0104] Specifically, the input to the decoder includes a video bitstream, which may be generated by the video encoder 200. The bitstream is first entropy decoded (330) to obtain transform coefficients, prediction modes, motion vectors, and / or other decoded information. Picture partition information indicates how the picture is partitioned. Thus, the decoder may partition (335) the picture according to the decoded picture partition information. The transform coefficients are dequantized (340) and inverse transformed (350) to decode the prediction residual. The image block is reconstructed by combining (355) the decoded prediction residual and the predicted block. The predicted block may be obtained (370) from intra-frame prediction (360) or motion compensated prediction (i.e., inter-frame prediction) (375). An in-loop filter (365) is applied to the reconstructed image. The filtered image is stored at a reference picture buffer (380). In some examples, for a given picture, the contents of reference picture buffer 380 at decoder 300 side may be the same as the contents of reference picture buffer 280 at encoder 200 side (eg, for the same picture).

[0105] The decoded picture may also undergo post-decoding processing (385), such as an inverse color transform (e.g., a transform from YCbCr 4:2:0 to RGB 4:4:4) or an inverse remapping that performs the inverse of the remapping performed in the pre-encoding process (201). The post-decoding processing may use metadata derived in the pre-encoding process and signaled in the bitstream. 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 transmitted to a display device for presentation to a user.

[0106] Figure 4 4 is a 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.

[0107] 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.

[0108] 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. In addition, 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.

[0109] 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 or partially decoded video, bitstreams, matrices, variables, and intermediate or final results of processing equations, formulas, operations, and operation logic.

[0110] 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.

[0111] 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.

[0112] 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.

[0113] 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.

[0114] 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).

[0115] 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.

[0116] 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.

[0117] 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.

[0118] 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.

[0119] 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.

[0120] 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, optical memory devices, magnetic memory devices, semiconductor-based memory devices, fixed memory, and removable memory. Processor 410 may be of any type suitable for the technical environment and may include, as a non-limiting example, one or more of a microprocessor, a general-purpose computer, a special-purpose computer, and a processor based on a multi-core architecture.

[0121] Various specific implementations involve decoding. As used in this application, "decoding" may cover, 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 processes performed by decoders of various specific implementations described in this application, such as: obtaining a most probable mode (MPM) list associated with the current block; determining a test list of intra-frame prediction modes from the MPM list; testing a first intra-frame prediction mode, wherein the first intra-frame prediction mode is excluded from the test list or is not allowed to be tested due to wide-angle intra-frame prediction (WAIP) substitution; generating a prediction for the current block based on the tested intra-frame prediction mode; and decoding the current block using the prediction, etc.

[0122] 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.

[0123] Various specific implementations involve encoding. In a manner similar to the discussion above about "decoding", "encoding" as used in this application may cover, for example, all or part of the processes 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 coding, transforming, quantization, and entropy coding. In various examples, such processes also include or alternatively include processes performed by encoders of various specific implementations described in this application, such as: obtaining a most probable mode (MPM) list associated with a current block; determining a test list of intra-frame prediction modes from the MPM list; testing a first intra-frame prediction mode, wherein the first intra-frame prediction mode is excluded from the test list or is not allowed to be tested due to wide-angle intra-frame prediction (WAIP) substitution; generating a prediction for the current block based on the tested intra-frame prediction mode; and encoding the current block using the prediction, etc.

[0124] 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.

[0125] It should be noted that the syntax elements used herein (e.g., coding syntax regarding precision factor, shift, number of fractional bits, intra prediction mode, index, range, size, weight, flag, calculation, shape, etc.) are descriptive terms. Therefore, they do not exclude the use of other syntax element names.

[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 may be implemented in, for example, a method or process, a device, a software program, a data stream, or a signal. 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 may also be implemented in other forms (e.g., a device or program). The device may be implemented in, for example, appropriate hardware, software, and firmware. These methods may be implemented in, for example, a processor, which generally refers to a processing device, including, for example, a computer, a microprocessor, an integrated circuit, or a programmable logic device. The processor also includes communication equipment, such as, for example, a computer, a mobile phone, a portable / personal digital assistant ("PDA"), and other equipment that facilitates 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 may involve "determining" various pieces of information. Determining information may include, for example, one or more of estimating information, calculating information, predicting information, or retrieving information from a memory. Obtaining may include receiving, retrieving, constructing, generating, and / or determining.

[0130] Furthermore, the present application may refer to "accessing" various information. Accessing information may include, for example, one or more of receiving information, retrieving information (e.g., from a memory), storing information, moving information, copying information, calculating information, determining information, predicting information, or estimating information.

[0131] Additionally, the present application may refer to "receiving" various information. Like "accessing," receiving is intended to be a broad term. Receiving information may include, for example, one or more of accessing information or retrieving information (e.g., from a memory). 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). This can be extended to as many items as listed, as will be apparent to one of ordinary skill in this and related arts.

[0133] Moreover, as used herein, the term "signaling" means (among other things) indicating something to a corresponding decoder. The encoder signal may include, for example, an intra-prediction mode index (e.g., via signaling based on an MPM list), etc. In this way, in the 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 may 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" may 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 may generate a variety of signals formatted to carry, for example, storable or transmittable information. The information may include, for example, instructions for executing a method or data generated by one of the described specific implementations. For example, a signal may be formatted to carry a bit stream of the example. Such a signal may be formatted as, for example, an electromagnetic wave (e.g., using a radio frequency portion of a spectrum) or a baseband signal. Formatting may include, for example, encoding a data stream and modulating a carrier using the encoded data stream. The information carried by the signal may be, for example, analog or digital information. As is well known, a signal may be sent over a variety of different wired or wireless links. The signal may be stored on, or accessed or received from, a processor-readable medium.

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

[0136] Intra-frame prediction is a coding tool in video coding (e.g., hybrid video coding). Intra-frame prediction can be used to predict blocks. The encoder can select (e.g., the best) intra-frame prediction mode (e.g., in terms of rate-distortion). The encoder can signal an index (e.g., an index associated with the selected intra-frame prediction mode) to the decoder. The decoder can use the signaled index to perform the same prediction for (e.g., each) block performed by the encoder. Signaling the index of the selected intra-frame prediction mode can add additional overhead, thereby reducing the gain from intra-frame prediction. The index of the intra-frame prediction mode selected to predict a given block can be decoded to generate a most likely mode (MPM) set, which can reduce signaling overhead (e.g., if the selected intra-frame prediction mode index belongs to a list). Signaling the intra-frame prediction mode index that is decoded to create an MPM set can be referred to as signaling based on an MPM list. For example, video decoding using VVC and / or HEVC can be implemented by signaling based on an MPM list. In other video coding implementations (eg, ECM), multiple (eg, two) MPM lists may be implemented (eg, instead of one MPM list).Herein, signaling of a mode index (such as MPM list-based signaling) may be referred to as signaling of a mode.

[0137] One or more tools based on (e.g., derived from) decoded pixels surrounding a given block (e.g., in intra-prediction mode) can be used to (e.g., additionally and / or alternatively) limit signaling overhead (e.g., via ECM) . The decoded pixels can be used (e.g., possibly the best) to predict the block (e.g., in terms of rate-distortion). The first video decoding tool can be a decoder-side intra-mode derivation (DIMD). The second video decoding tool can be a template-based intra-mode derivation (TIMD). For example, the first and / or second tools can be used to reduce signaling overhead. The signaling tool can enable the decoder to obtain an index of an intra-prediction mode (e.g., possibly the best). In an example (e.g., using DIMD), a template of decoded pixels above and / or to the left of the current block can be analyzed to infer the directionality of the template, from which one or more (e.g., two) directional intra-prediction modes can be selected. For example, a prediction signal can be generated by mixing multiple (e.g., two) modes with a planar mode. In an example (e.g., using TIMD), several intra-prediction modes may be tested on a template of decoded pixels above and / or to the left of a current block. One or more (e.g., two) modes that produce the minimum sum of absolute transform differences (SATD) between the template of decoded pixels and the mode prediction of the template may be selected (e.g., retained or kept). For example, a prediction signal may be generated by applying the mode with the minimum SATD or mixing multiple (e.g., two) modes.

[0138] In examples (e.g., for non-square blocks, VVC and / or ECM), one or more (e.g., several) directional intra prediction modes may replace one or more other intra prediction modes to obtain (e.g., maximum) information from decoded reference samples around the current block while maintaining the same number of intra mode predictions (e.g., without increasing signaling overhead). TIMD may bypass signaling overhead. The replacement of intra prediction modes for TIMD may be adapted to rate-distortion efficiency.

[0139] Intra-prediction mode signaling may be provided in various video coding tools (e.g., ECM) and TIMD. In an example, 67 intra-prediction modes may be provided as core intra-prediction modes. Any edge direction present in a video (e.g., natural video) may be captured by a directional intra-prediction mode. Additional directional intra-prediction modes may be provided in a video coding, for example, 33 used in one video coding method (e.g., in HEVC) and 65 used in a second video coding method (e.g., in VVC), or another number.

[0140] Figure 5 Examples of intra prediction modes in video coding implementations (e.g., VVC and ECM) are illustrated. Directional intra prediction modes are Figure 5 are depicted as solid and dashed arrows to illustrate the various densities of intra prediction modes. For example, Figure 5 The solid lines in FIG. 3 depict the 33 intra prediction modes used in HEVC, while Figure 5 The combination of solid and dashed lines in may depict 65 intra prediction modes in VVC. A directional intra prediction mode may be applied to one or more (eg, all) block sizes and / or luma and / or chroma intra prediction.

[0141] Planar mode and DC mode may be similar in HEVC and VVC. In HEVC, (e.g., each) intra-coded block may have a square shape. The length of each side of the square shape may be a power of two (2). A division operation may not be implemented (e.g., in DC mode) to generate an intra-predictor. The block may have a rectangular shape (e.g., in VVC). A division operation may be implemented for each block (e.g., for a rectangular shape). The longer side may be used to calculate the average of non-square blocks, for example, to avoid a division operation (e.g., for prediction in DC mode).

[0142] In an example (eg, in ECM), there may be 67 intra prediction modes. Directional intra prediction modes may include four-tap or six-tap interpolation. Directional intra prediction modes may include position-dependent intra prediction combining (PDPC), which may be supplemented with gradient PDPC.

[0143] Intra-prediction mode signaling may be implemented, for example, in an ECM. Intra-prediction mode signaling may include signaling in luma. For example (e.g., in an ECM), if the intra-prediction mode selected to predict the current luma coding block (CB) is not DIMD, is not a matrix-based intra-prediction (MIP) mode, is not TIMD, and / or is one of 67 intra-prediction modes (e.g., as described herein), then an MPM list for the coding block (CB) may be used to signal an index. For example, if one or more tools are activated (e.g., exclusively) for one or more (e.g., specific) video sequences (e.g., screen content), then the one or more tools, such as block differential pulse coding modulation (BDPCM), template-based intra prediction (TMP), intra-block copy (IBC), and / or a palette, etc., may be ignored. The MPM list (e.g., in an ECM) may be decomposed into a list of one or more (e.g., 6) primary MPMs and a list of one or more (e.g., 22) secondary MPMs, such as Fig. 6A and Figure 6B As shown in the example in . The MPM list can be constructed (e.g., sequentially constructed) by adding candidate intra-frame prediction mode indices. The MPM list can be sorted from the candidate intra-frame prediction mode index that is most likely to be selected as the intra-frame prediction mode for predicting the current brightness CB to the candidate intra-frame prediction mode index that is least likely to be selected as the intra-frame prediction mode for predicting the current brightness CB.

[0144] Fig. 6A and Figure 6B An example derivation of an MPM list for a current luma CB belonging to an intra slice (eg, as implemented in ECM) is illustrated.

[0145] Fig. 6A and Figure 6B The (eg, sequential) addition of candidate intra prediction mode indices is shown (eg, from left to right), eg, where the current luma CB belongs to an intra slice. Redundancy may not exist in the MPM list, eg, there may not be identical intra prediction mode indices. Fig. 6A and Figure 6BAn example is illustrated in which each candidate intra-frame prediction mode index is different from each other. In the example, the time slots of indexes 0 to i-1 included in the MPM list may have been filled. For example, if the current candidate intra-frame prediction mode index already exists in the current MPM list, the candidate can be skipped, and for example, if the next candidate intra-frame prediction mode does not exist in the MPM list, the next candidate intra-frame prediction mode can be inserted at the time slot of index i. For example, if the current intra-frame prediction mode index does not exist in the MPM list, the current intra-frame prediction mode index can be inserted at the time slot of index i, and for example, if the next candidate intra-frame prediction mode index does not exist in the MPM list, the next candidate intra-frame prediction mode index can be inserted at the time slot of index i+1.

[0146] Fig. 7A and Figure 7B An example of signaling the intra prediction mode selected to predict the current luma CB in the ECM is illustrated. Fig. 7A and Figure 7B The shown example describes signaling the intra prediction mode selected to predict the current luma CB at the encoder side. The example is applicable at the decoder side. Fig. 7A Involving multiple reference lines (MRL). Fig. 7A As shown, for example, if the TIMD flag is equal to 1, the MRL index may belong to {0, 1, 3}. An MRL index equal to 0 may indicate that the MRL is not used to predict the current brightness CB. An MRL index equal to 1 may indicate that the second row of decoded reference samples above the current brightness CB and the second column of decoded reference samples to the left of the current brightness CB are used for prediction. An MRL index equal to 3 may indicate that the fourth row of decoded reference samples above the current brightness CB and the fourth column of decoded reference samples to the left of the current brightness CB are used for prediction. Fig. 7A As shown, for example, if the TIMD flag is equal to 0, the MRL index may belong to {0, 1, 3, 5, 7, 12}. Fig. 7A Refers to the Internal Sub-Partition (ISP). Fig. 7A As shown, the ISP mode index may belong to {0, 1, 2}. An ISP mode index equal to 0 may indicate that the ISP is not used for the current luma CB. An ISP mode index equal to 1 may indicate that the current luma CB is horizontally divided into luma transform blocks (TBs). An ISP mode index equal to 2 may indicate that the current luma CB is vertically divided into luma TBs. Fig. 7A and Figure 7B In the example shown, for example, if one or more tools (such as BDPCM, TMP, IBC, and / or Palette) are enabled for one or more video sequences, these tools may be omitted.

[0147] The intra prediction mode may be signaled for predicting chroma. Figure 8An example of signaling the intra prediction mode selected to predict the current chroma CB pair (eg, as implemented in an ECM) is illustrated. Figure 8 An example of signaling the intra prediction mode selected to predict the current chroma CB pair (e.g., the collocated Cb and Cr CBs) is illustrated. Figure 8 As shown in the example in , multiple (e.g., four) possibilities for the current intra-frame prediction mode index may include an index of a plane mode, an index of a horizontal mode, an index of a vertical mode, and an index of a DC (e.g., if the direct mode (DM) flag is equal to 1). For example, if one of the modes in the set of (e.g., four) modes is DM, redundancy in the set of modes may be avoided. In such examples, the index of the redundant mode may be replaced by the index of the vertical diagonal mode. For example, in ECM, a cross-component linear model (CCLM) may include multiple (e.g., six) different intra-frame prediction modes, such as LM, MMLM, MDLM_L, MDLM_T, MMLM_L, and MMLM_T. For example, in VVC, CCLM may include multiple (e.g., three) different intra-frame prediction modes.

[0148] Wide angle intra prediction (WAIP) may be implemented. One or more (e.g., several) angular intra prediction modes may be supplemented or replaced with a wide angle mode, for example, as implemented for non-square blocks in VVC and / or ECM. The replaced mode may be signaled (e.g., using the original method) and remapped to the index of the wide angle mode (e.g., after parsing). In an example, the total number of (e.g., core) intra prediction modes may remain unchanged (e.g., 67).

[0149] Fig.9A and Fig. 9B An example of a set of decoded reference samples for a current W×H block to be predicted is illustrated, including an array of top decoded reference samples of length equal to 2W+1 and an array of left decoded reference samples of length equal to 2H+1. Fig.9A and Fig. 9B The relationship between the range of decoded reference samples around the current W×H block and the range of allowed intra prediction angles is shown.

[0150] Table 1 presents examples of indices of intra prediction modes replaced by wide mode in VVC and ECM (eg, depending on the size of the current block to be predicted).

[0151] FIG. 9A to FIG. 9B An example relationship between a range of a set of decoded reference samples around (eg, surrounding) a current W×H block to be predicted and a range of allowed intra-prediction angles is illustrated.

[0152] Table 1 - Example of indices of intra prediction modes replaced by wide angle mode (e.g., as used in VVC and ECM) For example, it may have, for example, 67 (eg, core) intra prediction modes. .

[0153]

[0154]

[0155] Fig.10 An example of how the angular intra mode can be replaced by the wide mode for non-square blocks whose width is (eg, strictly) greater than their height is illustrated. Fig.10 As shown in the example in , mode 2 may be replaced by wide mode 67. Mode 3 may be replaced by wide mode 68. For example, the current block to be predicted may be 8×4. The process of substitution may continue (e.g., incrementally) until mode 7 is replaced by wide mode 72.

[0156] Template-based intra mode derivation (TIMD) can be implemented. Intra prediction mode derivation via TIMD can be performed for a given brightness (such as Fig.11A CB (103) shown) is applied on the encoder side and the decoder side (e.g., in the same way). (e.g., each) intra-frame prediction mode in the MPM list of the luma CB (e.g., supplemented with a default mode) can (e.g., if necessary) calculate a prediction of the template (1100 and 1101) of the luma CB from the decoded reference samples (1102) of the template. The SATD between the prediction and the template of the luma CB can be calculated. The (e.g., two) intra-frame prediction modes with the smallest (e.g., the smallest) SATD can be selected as the TIMD mode. This can be done, for example, by Figure 5 The set of directional intra prediction modes is expanded (e.g., from 65 to 129) (e.g., for TIMD) by inserting directions between each solid line and adjacent dashed line in . The set of possible intra prediction modes derived via TIMD can collect 131 modes. One or more (e.g., two) intra prediction modes can be retained from the first pass test involving the MPM list, which can be supplemented with a default mode. TIMD can test (e.g., for each retained intra prediction mode that is not PLANAR or DC) the (e.g., two) closest extended directional intra prediction modes (e.g., in terms of predicting SATD). In the example, it can be assumed that the template of the luma CB does not exceed the boundary of the current frame. Fig. 11B and Fig. 11C An example is shown in which at least a portion (eg, a part) of the template of the luminance CB exceeds the boundary of the current frame.

[0157] The current luma CB may be predicted via TIMD, for example, by fusing (e.g., two) predictions of the luma CB via (e.g., two) TIMD modes, which are generated by multiple (e.g., two) passes of testing using weights (e.g., after applying PDPC). The weights used (e.g., the calculated weights) may depend on the predicted SATD of the (e.g., two) TIMD modes. In an example, the generated prediction may be based on the calculated weights. The calculated weights may include a first calculated weight associated with a tested first intra-frame prediction mode and a second weight associated with a tested second intra-frame prediction mode.

[0158] FIG. 11A to FIG. 11C An example of a template of the current luma CB and decoded reference samples of the template is illustrated. Fig.11A shows that the current W×H brightness CB (1103) is surrounded by a completely usable template, including w on the left t The W×H portion (1100) and the W×H portion above the current W×H brightness CB (1103) t Example of part (1101). The tested intra prediction mode may be selected (e.g., during the TIMD derivation step) according to the 1+2w of the template. t +2W+2h t +2H decoded reference samples (1102) predict the template of the current brightness CB. In one example (e.g., ECM), if W≤8, then w t is equal to 2, and otherwise w t is equal to 4. In one example, if H≤8, then h t is equal to 2, and otherwise h t Equals 4. Fig. 11B An example is shown in which the current W×H brightness CB (1103) is surrounded by a template, where the W×h above the current W×H brightness CB (1103) t Part (1101) is available. The tested intra prediction mode can be (e.g., during the TIMD derivation step) based on the template's 1+2W+2h t The set of +2H decoded reference samples (1102) predicts the template of the current brightness CB. Fig. 11C An example is shown in which the current W×H brightness CB (1103) is surrounded by a template, where w on the left t The ×H part (1100) is available. The tested intra prediction mode can be (e.g., during the TIMD derivation step) based on the 1+2w of the template t The set of +2W+2H decoded reference samples (1102) predicts the template of the current brightness CB.

[0159] For example, for TIMD, the set of directional intra prediction modes can be extended from 65 to 129. For example, as shown in Table 2, intra prediction mode replacement in WAIP can be adapted. For example, TIMD can be used given an 8×4 luma CB. Mode 2 can be replaced by wide-angle mode 131, mode 3 can be replaced by wide-angle mode 132, mode 4 can be replaced by wide-angle mode 133, ..., mode 12 can be replaced by wide-angle mode 141, etc. Multiple intra prediction mode indexes can be generated, and multiple intra prediction mode indexes can be used to generate a prediction for the current block. Weights of multiple intra prediction mode indexes can be calculated. One of the weights can be a sum of absolute transform differences (SATD), and a prediction for the current block can be generated based on a subset of intra prediction mode indexes with the minimum predicted SATD from multiple intra prediction mode indexes.

[0160] Table 21 - Example of index of intra prediction mode replaced by wide angle mode in TIMD in ECM .

[0161] condition 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|]

[0162] Template-based intra mode derivation (TIMD) may be implemented. TIMD may be implemented by extending WAIP. A tested intra prediction mode may be selected from the MPM list of the current luma CB during the TIMD derivation process. The selected intra prediction mode may be supplemented with a default mode. The selected mode may (e.g., if desired) undergo WAIP substitution (e.g., as described herein). For example, if / when TIMD is applied to a non-square luma CB, the tested intra prediction mode may not be removed by the wide angle process.

[0163] For example, the efficiency of TIMD can be improved by making one or more (e.g., all) intra prediction modes (e.g., wide angle or non-wide angle) available for TIMD. In an example (e.g., a specific implementation), the number of modes tested can be limited to reduce the complexity of the search for the best TIMD candidate. An example (e.g., all examples) can be implemented without additional signaling, regardless of the selected mode.

[0164] Directional intra prediction mode replaced by WAIP for rectangular CUs may be allowed. FIG. 12A to FIG. 12B As shown), alternative intra prediction modes may be allowed (eg, due to a wide-angle process when performing TIMD on a rectangular CU).

[0165] FIG. 12A to FIG. 12B Examples of direction ranges added by WAIP and direction ranges replaced by WAIP are illustrated. Direction ranges replaced by WAIP are allowable.

[0166] In an example (e.g., based on Table 2), a range of [|2,28|] of intra-prediction mode indices may be allowed for a current 16×4 luma CB using TIMD. A range of intra-prediction mode indices generated by a WAIP process may (e.g., also) be allowed (e.g., [|131,157|]). In (e.g., another) example, a range of [|2,30|] of intra-prediction mode indices may be allowed for a current 32×4 luma CB using TIMD. A range of intra-prediction mode indices generated from a WAIP process may (e.g., also) be allowed (e.g., [|131,159|]). In an example, a span of directional intra-prediction modes in TIMD in an ECM may be used. The example (e.g., as described herein) may be extended to (e.g., any) span of a directional space for intra-prediction modes. In an example (e.g., as described herein), a specific implementation (e.g., using TIMD) may be adapted to be more specific than Figure 5 The example in FIG. 4 shows a density four times greater than the density of the directional intra prediction modes, which can be achieved, for example, by Figure 5 This is achieved by adding three directions between each solid line and the adjacent dashed line.

[0167] Intra prediction modes allowed for CUs of similar shapes may be allowed for CUs of other sizes. For example, if / when TIMD is performed on a CU of a certain size, modes that would be authorized for other CUs with similar shapes may be allowed.

[0168] For example, TIMD may be performed on a square CU. For example, in addition to other intra prediction modes (e.g., TIMD search is not restricted), wide angles that may be allowed for CUs with a width / height ratio of 1 / 2 or 2 / 1 may be allowed. For example, TIMD may be performed on a CU with a width / height ratio of 2 / 1 (e.g., or 1 / 2). The modes allowed in TIMD may include modes that may be allowed for CUs with a width / height ratio of 4 / 1 or 1 / 1 (e.g., or 1 / 4 or 1 / 1).

[0169] In an example, a current 4×4 luma CB may use TIMD. As described herein, a wide angle that would be allowed for an 8×4 luma CB and / or for a 4×8 luma CB may (e.g., additionally) be allowed for a 4×4 luma CB. For example, TIMD applied to a 4×4 luma CB may use (e.g., in addition to the intra prediction modes allowed for the 4×4 luma CB) Fig. 12A and Fig. 12B The right part of the added range contains 10 patterns and Fig. 12A and Fig. 12B In the left part of the added range there are 10 patterns.

[0170] Fig.13An example of a range of directions added by WAIP and a range of directions replaced by WAIP when a reference sample of a current block is a square is illustrated. The current block may be associated with a first shape, and a first intra prediction mode (e.g., a mode that is excluded from a test list or is not allowed to be tested due to WAIP substitution) may be associated with a second shape. The second shape may be associated with the direction replaced by WAIP. For example, for a rectangular block, before the mode is replaced, the mode may be rectangular. For example, for WAIP substitution, the replaced mode may correspond to a shape (e.g., a square shape). Fig.13 In the embodiment of the present invention, for example, mode 2 may be at 45 degrees and follow the characteristics of using square blocks. The first shape may be a square, and the second shape may be a rectangle. The lengths of adjacent sides of the second shape may be different from each other. Fig.13 It is illustrated that intra prediction modes (e.g., potential intra prediction modes) may be used for a current block using TIMD. WAIP modes reserved for neighboring block sizes (e.g., W / H=2 (modes 131 to 141) and W / H=0.5 (modes 1 to 9)) may be allowed or included in the TIMD search for the current block, and for example, when W / H=4 and W / H=0.25, etc.

[0171] Fig.14 An example of a range of directions added by WAIP and a range of directions replaced by WAIP when the reference sample of the current block is rectangular is illustrated. The current block may be associated with a first shape, and a first intra prediction mode (e.g., a mode excluded from a test list or not allowed to be tested due to WAIP substitution) may be associated with a second shape. The second shape may be associated with the direction replaced by WAIP. For example, for a square block, before replacing the mode, the mode may be square. For example, for WAIP substitution, the replaced mode may correspond to a shape (e.g., a rectangular shape). Fig.13 In, for example, mode 13 may be at 45 degrees and follow the characteristics of using rectangular blocks. The first shape may be a rectangle, and the second shape may be a square. The lengths of adjacent sides of the first shape may be different from each other. Fig.13 and Fig.14 For example, WAIP may use a wide angle that will be allowed for a CU (e.g., other CUs) without limiting TIMD searches. WAIP modes reserved for neighboring block sizes (e.g., W / H=1 (2 to 12) and W / H=4 (142 to 149)) may be allowed in TIMD searches for the current block, and, for example, when W / H=0.5 and W / H=8, etc.

[0172] Tests may be added for directional intra prediction modes allowed during TIMD derivation. As described herein in various examples, intra prediction modes may be additionally allowed for TIMD. Tests for additional intra prediction modes may be added to TIMD derivation. Fig.15 An example workflow for TIMD derivation of the current block to be predicted is illustrated. Fig.15 As shown, the location or implementation order of the additional test groups within the TIMD-derived workflow may vary. Fig.16 As shown in the example in After the extended directional intra prediction mode of the neighbors, an additional set of tests may occur. Fig.17 As shown in the example of , an additional set of tests may be performed before collecting the MPM list for the current block. The size of the current block to be predicted may be known. The intra prediction mode replaced by WAIP and / or the wide angle mode not considered for the block size (e.g., the first intra prediction mode) may be known. The testing of the intra prediction mode replaced by WAIP and / or the wide angle mode not considered for the block size may occur before the determination of the test list.

[0173] Fig.15 Examples of TIMD derivation for a current block to be predicted are illustrated, for example, if / when one or more additional directional intra prediction modes are allowed (eg, as described herein). Fig.15 The example TIMD derivation process shown describes the TIMD derivation in the ECM and the test for the additionally allowed directional intra prediction modes. Fig.15 As shown, It may represent, for example, the indices of the two intra prediction modes that produce the two minimum predicted SATDs on the template of the current block (e.g., after the first pass test). Fig.15 As shown, i0, i1 may represent the indices of two patterns that produce two minimum predicted SATDs on the template of the current block (eg, after the second pass test).

[0174] like Fig.15As illustrated, 1502 to 1512 may include steps associated with the derivation step of the TIMD process, and 1514 may be associated with the prediction step of the TIMD process. At 1502, the MPM list of the current block may be collected. At 1504, a test list of intra prediction modes may be constructed. The intra prediction mode may be tested from the MPM list. A default mode (e.g., DC, horizontal and / or vertical) may be included. At 1506, the modes in the test list (e.g., some modes) may be tested, and WAIP substitution may be applied to the test (e.g., each test). At 1508, additional modes that are suppressed by WAIP substitution and / or are not allowed (e.g., not allowed in the test list) due to the size of the current block may be tested. At 1510, adjacent extended (e.g., some extended) directional intra prediction modes i0 and i1 may be tested. At 1512, weights w0, w1 associated with the intra prediction mode may be calculated for mixing. At 1514 , as part of the prediction, the current block may be predicted via the mode of index i0 or by mixing two predictions from the modes of index i0 , i1 with weights w0 , w1 .

[0175] like Fig.16 As illustrated, 1602 through 1612 may include steps associated with a derivation step of the TIMD process, and 1614 may be associated with a prediction step of the TIMD process. Fig.16 An example of a TIMD derivation process for a current block to be predicted, for example, if / when one or more additional directional intra prediction modes are allowed (e.g., as described herein) is illustrated. At 1602, an MPM list for the current block may be collected. At 1604, a test list of intra prediction modes may be constructed. The intra prediction mode may be tested from the MPM list. A default mode (e.g., DC, horizontal and / or vertical) may be included. At 1606, modes (e.g., some modes) in the test list may be tested, and WAIP substitution may be applied to the test (e.g., each test). At 1608, adjacent extended (e.g., some extended) directional intra prediction modes i0 and i1 may be tested. At 1610, additional modes that are suppressed by WAIP substitution and / or are not allowed (e.g., not allowed in the test list) due to the size of the current block may be tested. At 1612, weights w0, w1 associated with the intra prediction mode may be calculated for mixing. At 1614 , the current block may be predicted via the mode of index i0 or by mixing the two predictions from the mode of index i0 , i1 with weights w0 , w1 .

[0176] like Fig.17 As illustrated, 1702 through 1712 may include steps associated with a derivation step of the TIMD process, and 1714 may be associated with a prediction step of the TIMD process. Fig.17An example of a TIMD derivation process for a current block to be predicted, for example, if / when one or more additional directional intra prediction modes are allowed (e.g., as described herein) is illustrated. At 1702, additional modes that are suppressed by WAIP substitution and / or are not allowed (e.g., not allowed in a test list) due to the size of the current block may be tested. At 1704, an MPM list for the current block may be collected. At 1706, a test list of intra prediction modes may be constructed. Intra prediction modes may be tested from the MPM list. Default modes (e.g., DC, horizontal and / or vertical) may be included. At 1708, modes in the test list (e.g., some modes) may be tested, and WAIP substitution may be applied to the tests (e.g., each test). At 1710, adjacent extended (e.g., some extension) directional intra prediction modes i0 and i1 may be tested. At 1712, weights w0, w1 associated with the intra prediction modes may be calculated for mixing. At 1714 , the current block may be predicted via the mode of index i0 or by mixing two predictions from the modes of index i0 , i1 with weights w0 , w1 .

[0177] In an example (eg, involving additional testing), a given block may be predicted based on (eg, all) additional allowed intra-prediction modes tested (eg, systematically) during the TIMD derivation process.

[0178] In an example (e.g., involving additional testing), additional allowed intra-frame prediction modes may be tested based on certain scenarios (e.g., under certain scenarios). For example, if the non-wide-angle intra-frame prediction mode closest to the additional allowed intra-frame prediction mode belongs to a test list (e.g., where the non-wide-angle intra-frame prediction mode has been tested or will be tested during the TIMD export process), one or more additional allowed intra-frame prediction modes may be tested (e.g., during the TIMD export process). For example, the TIMD export process may be implemented for the current 8×4 luma CB. Directional intra-frame prediction modes replaced by WAIP may be allowed. The additional allowed intra-frame prediction mode index may belong to [|2,12|], for example, as shown in Table 2. For example, if the intra-frame prediction mode of index 13 belongs to the test list, the additional allowed intra-frame prediction modes (e.g., all additional allowed intra-frame prediction modes) may be tested. In (e.g., another) example (e.g., during the TIMD export process), for example, if the non-wide-angle intra-frame prediction mode closest to the additional allowed intra-frame prediction mode belongs to a test list (e.g., where the non-wide-angle intra-frame prediction mode has been tested or will be tested during the TIMD export process), one or more additional allowed intra-frame prediction modes may be tested (e.g., during the TIMD export process). At least one of the non-wide-angle intra prediction modes belongs to the test list (eg, At least one of the non-wide-angle intra prediction modes has been tested or will be tested during the TIMD derivation process), the additional allowed intra prediction mode may be tested. As an example, the TIMD derivation process may be implemented for the current 8×4 luma CB and p=3. The directional intra prediction mode replaced by WAIP may be allowed. The additional allowed intra prediction mode index may belong to [|2,12|], for example, as shown in Table 2. For example, if the intra prediction mode of index 15 belongs to the test list, the additional allowed intra prediction modes (e.g., all additional allowed intra prediction modes) may be tested.

[0179] In an example (eg, involving additional testing), the additional allowed intra prediction mode may be tested if / when at least one of the directional intra prediction modes having an opposite direction with respect to the additional allowed mode belongs to the test list.

[0180] In an example (e.g., involving additional testing), the decision to test an additional allowed intra-prediction mode may depend on the SATD between the template of the current block and the prediction of the template via the tested intra-prediction modes. In the example, if, for the non-Wide-angle intra-prediction mode that is closest to the additional allowed intra-prediction mode, the SATD between the template of the current block and the mode prediction belongs to one of the modes tested so far. If a set of minimum predicted SATDs is found, then additional allowed intra prediction modes may be tested. In this example, if for an additional allowed intra prediction mode, the SATD between the template of the current block and the mode prediction belongs to one of the modes tested so far. If a set of minimum predicted SATDs is found, then (e.g., all) additional allowed intra prediction modes may be tested. In an example, the SATD between the template of the current block and the prediction of the template via the mode may be used as a criterion for ranking different intra prediction modes. In an example, a distortion metric between the template of the current block and the mode prediction of the template may be used (e.g., as a criterion for ranking different intra prediction modes).

[0181] The intra prediction modes used by TIMD and WAIP may be stored. For example, the intra prediction modes to be stored may be used to generate an MPM list of luma CBs surrounding the current luma CB. The stored modes may be, for example, the closest mode or a mode with an opposite direction.

[0182] For example, if the mode selected by the TIMD is in the range [|131, 141|] for a square luma CB, where modes for close-shaped CUs are allowed and where angular modes with a range [|2, 130|] are to be used without additional modes (e.g., supplemented by planar and DC modes), the closest mode 130 may be stored. In another example, if an angular mode with a range [|-9, 1|] is selected, mode 2 may be stored. In another example of a luma CB of size 16×8 with allowed angular modes [|13, 141|], if the selected mode is less than 13, mode 13 may be stored, and if the selected mode is higher than 141, mode 141 may be stored.

[0183] In the example of storing a mode with an opposite direction, if the mode selected by the TIMD is the original mode 2 (45° from the lower left) and if mode 2 is removed in the horizontal block, the stored mode may be the original mode 130 (45° from the upper right). In the example of a square luma CB, when the mode used is below 34 (e.g., full horizontal mode), the stored mode may be equal to 128 plus the value of the mode used. In the example of a square luma CB, when the mode used is above 98 (e.g., full vertical mode), the stored mode may be equal to the mode used minus 128. In examples (e.g., even with WAIP), there may not be a mode opposite to the mode between 34 and 98, because such an opposite mode would use a reference sample to the right or below the current luma CB.

[0184] For example, an additional flag may be stored to signal the TIMD that the mode used is not the mode that would have been used for (eg, conventional) intra prediction on the block shape to allow the correct mode to be stored.

[0185] Additional decoded reference samples may be provided to the TIMD. During the TIMD derivation process, the intra-prediction mode replaced by the WAIP process may be tested after the additional mode is allowed. The process of predicting a template of a current block based on the decoded reference samples of the template may lack decoded reference samples. During the prediction step via TIMD, the process of predicting a current block based on the decoded reference samples of the current block may lack decoded reference samples, for example, if an intra-prediction mode replaced by WAIP but allowed after the additional mode is allowed is selected. Providing additional decoded reference samples to the TIMD during TIMD derivation and / or during prediction via TIMD may compensate (e.g., make up for) the lack of decoded reference samples.

[0186] Decoded reference samples may be added for additional allowed intra prediction modes. For additional allowed intra prediction modes (e.g., allowed as described herein), decoded reference samples may be added for a given block to be predicted (e.g., during TIMD derivation and / or prediction via TIMD). At least one decoded reference sample may be added for a first intra prediction mode (e.g., an intra prediction mode that is excluded from a test list or not allowed to be tested due to wide angle intra prediction (WAIP) substitution). The added decoded reference samples may correspond to decoded reference samples that may be used for prediction.

[0187] In the example for a rectangular W×H block (W>H), one or more intra prediction modes replaced by the WAIP process may be allowed. Prediction may occur via TIMD. The W decoded reference samples below the current block may be considered for prediction via the additional allowed intra prediction modes (e.g., similar to a square W×W block). 18A to 18C An example of adding decoded reference samples for TIMD derivation and prediction via TIMD is illustrated. In the example for a W×H rectangular block (H>W), the H decoded reference samples to the right of the current block can be considered for prediction via additional allowed intra prediction modes (e.g., similar to a square H×H block). FIG. 19A to FIG. 19C An example of adding decoded reference samples for TIMD derivation and prediction via TIMD is illustrated. 18A to 18C and 19A to Fig.19C As shown in the example in , the dotted line indicates an angle of +45 degrees in the clockwise direction. 18A to 18C The bottom-most decoded reference sample is shown to be extrapolated by the intra-prediction mode of index 2 (eg, for TIMD derivation and prediction via TIMD) using the mode index in the ECM (eg, without considering interpolation of decoded reference samples for directional modes). FIG. 19A to FIG. 19C The rightmost decoded reference sample extrapolated by the intra prediction mode of index 130 using the mode index of the TIMD in the ECM (e.g., without considering interpolation of decoded reference samples for directional modes) is shown (e.g., for TIMD derivation and prediction via TIMD). The dashed line depicts the last decoded reference sample that can be used (e.g., exclusively) for prediction (e.g., without considering interpolation of decoded reference samples for directional modes and PDPC).

[0188] 18A to 18C An example of adding decoded reference samples during TIMD derivation and prediction via TIMD for a rectangular W×H block to be predicted (W>H) when one or more directional intra prediction modes replaced by WAIP are allowed is illustrated. Fig.18AAs shown, a current block (1803) may be surrounded by TIMD templates (1800 and 1801) during TIMD derivation. The tested intra prediction modes may predict the template of the current block based on the decoded reference samples (1802 and 1804) of the templates. The added decoded reference samples (e.g., one or more allowed additional directional intra prediction modes replaced for WAIP) are indicated as 1804. Fig.18B and Fig.18C As shown, during prediction via TIMD, (e.g., each) intra prediction mode derived via TIMD may predict the current block (1803) based on the associated decoded reference samples (1805 and 1806). The added decoded reference samples (e.g., one or more additional allowed directional intra prediction modes replaced for WAIP) are represented as 1806. Fig.18B An example of prediction via TIMD is illustrated, where the MRL index denoted multiRefIdx is equal to 0. Fig.18C An example of prediction via TIMD is illustrated, where multiRefIdx>0.

[0189] FIG. 19A to FIG. 19C An example of adding decoded reference samples during TIMD derivation and prediction via TIMD for a rectangular W×H block to be predicted (H>W) when one or more directional intra prediction modes replaced by WAIP are allowed is illustrated. Fig.19A As shown, a current block (1903) may be surrounded by TIMD templates (1900 and 1901) during TIMD derivation. The tested intra prediction modes may predict the template of the current block based on the decoded reference samples (1902 and 1904) of the templates. The added decoded reference samples (e.g., one or more allowed additional directional intra prediction modes replaced for WAIP) are indicated as 1904. Fig.19B and Fig.19C As shown, during the prediction step via TIMD, the (e.g., each) mode derived via TIMD may predict the current block (1903) based on the associated decoded reference samples (1905 and 1906). The added decoded reference samples (e.g., one or more allowed additional directional intra prediction modes replaced for WAIP) are represented as 1906. Fig.19B An example of prediction via TIMD is illustrated, where the MRL index denoted multiRefIdx is equal to 0. Fig.19C An example of prediction via TIMD is illustrated, where multiRefIdx>0.

[0190] In an example (e.g., during TIMD derivation for a rectangular W×H block, W>H), more decoded reference samples of a template of a current block located at the bottom of the current block may be extracted for prediction via an additional allowed intra-prediction mode. In an example (e.g., during TIMD derivation for a rectangular W×H block, H>W), more decoded reference samples of a template of a current block located at the rightmost of the current block may be extracted for prediction via an additional allowed intra-prediction mode. FIGS. 20 and 21 show examples of extracting more decoded reference samples for prediction compared to FIGS. 18 and 19, respectively.

[0191] FIG. 20A to FIG. 20C An example of adding decoded reference samples during TIMD derivation (e.g., 20A) and prediction via TIMD (e.g., 20B and 20C) for a rectangular W×H block to be predicted (W>H) when one or more directional intra prediction modes replaced by WAIP are allowed is illustrated. Fig. 20A As shown, a current block (2003) (e.g., a horizontal and rectangular current block) may be surrounded by TIMD templates (2000 and 2001) during TIMD derivation. The tested intra prediction modes may predict the template of the current block based on the decoded reference samples (2002 and 2004) of the templates. The added decoded reference samples (e.g., one or more allowed additional directional intra prediction modes replaced for WAIP) are indicated as 2004. Fig. 20B and Fig. 20C As shown, during prediction via TIMD, (e.g., each) intra prediction mode derived via TIMD may predict the current block (2003) based on the associated decoded reference samples (2005 and 2006). The added decoded reference samples (e.g., one or more additional allowed directional intra prediction modes replaced for WAIP) are represented as 2006.

[0192] FIG. 21A to FIG. 21C An example of adding decoded reference samples during TIMD derivation (e.g., 21A) and prediction via TIMD (e.g., 21B and 21C) for a rectangular W×H block to be predicted (H>W) when one or more directional intra prediction modes replaced by WAIP are allowed is illustrated. Fig.21A As shown, a current block (2103) (e.g., a vertical and rectangular current block) may be surrounded by a TIMD template (2100 and 2101) during TIMD derivation. The tested intra prediction mode may predict the template of the current block based on the decoded reference samples (2102 and 2104) of the template. The added decoded reference samples (e.g., one or more allowed additional directional intra prediction modes replaced for WAIP) are indicated as 2004. Fig. 21B and Fig. 21CAs shown, during prediction via TIMD, (e.g., each) intra prediction mode derived via TIMD may predict the current block (2103) based on the associated decoded reference samples (2105 and 2006). The added decoded reference samples (e.g., one or more additional allowed directional intra prediction modes replaced for WAIP) are represented as 2106.

[0193] In the example (for example, 18A to 18C , FIG. 19A to FIG. 19C , FIG. 20A to FIG. 20C and FIG. 21A to FIG. 21C ), the current block may be predicted by replacing the unavailable decoded reference samples in each decoded reference sample set. For example, according to the replacement implemented in VVC and ECM, the replacement may replace the unavailable decoded reference samples. The examples described herein (e.g., 18A to 18C , FIG. 19A to FIG. 19C , FIG. 20A to FIG. 20C and FIG. 21A to FIG. 21C ) can be adapted or generalized to predict a current block based on a portion of the template being available (eg, where another portion of the template is outside the boundaries of the current frame).

[0194] In an example (e.g., for a current block of a size using TIMD), additional allowed intra-prediction modes (e.g., intra-prediction modes replaced by WAIP) may be authorized for blocks of a similar shape. Decoded reference samples used by authorized intra-prediction modes for blocks of a similar shape may be extracted (e.g., if possible) for TIMD derivation and prediction using TIMD. In an example (e.g., in the case of a current W×W block to be predicted), a CU of a similar shape may have width / height ratios of 1 / 2 and 2 / 1. Prediction via TIMD may consider 2W decoded reference samples below the current block and 2W decoded reference samples to the right of the current block for prediction via additional allowed intra-prediction modes (e.g., as FIG. 22A to FIG. 22C ). Fig. 22B As shown, the dotted lines indicate two angles of two extremely wide-angle intra prediction modes that are additionally allowed (e.g., modes allowed for CUs close to the shape). The extreme wide-angle intra prediction mode for the wide-angle intra prediction mode propagating from the upper right to the lower left may refer to the mode with the smallest angle (in absolute value) with the horizontal axis. The extreme wide-angle intra prediction mode for the wide-angle intra prediction mode propagating from the lower left to the upper right may refer to the mode with the smallest angle with the vertical axis.

[0195] FIG. 22A to FIG. 22CAn example of adding decoded reference samples during TIMD derivation (e.g., 22A) and prediction via TIMD (e.g., 22B and 22C) for a square W×W block to be predicted is illustrated. A current block (2203) may be surrounded by an associated TIMD template (2200 and 2201) during TIMD derivation. The tested intra-frame prediction mode may predict the template of the current block based on the decoded reference samples (2202 and 2204) of the template. The added decoded reference samples (e.g., according to one or more examples described herein) are represented as 2204. The (e.g., each) prediction mode derived via TIMD may predict the current block (2203) based on the associated decoded reference samples (2205 and 2206) during prediction via TIMD. The added decoded reference samples according to the first embodiment may be represented as 2206. Fig. 22B An example of prediction via TIMD is illustrated, where the MRL index denoted multiRefIdx is equal to 0. Fig. 22C An example of prediction via TIMD is illustrated, where multiRefIdx>0.

[0196] In an example, additional decoded reference samples of the template of the current block may be extracted (e.g., during TIMD derivation) for prediction via additional allowed intra prediction modes. The additional decoded reference samples may be located at the very bottom of the current block and at the very right of the current block. FIG. 23A to FIG. 23C The example shown is similar to FIG. 22A to FIG. 22C The examples shown are compared for improved understanding of the examples.

[0197] FIG. 23A to FIG. 23C An example of adding decoded reference samples during TIMD derivation (e.g., 23A) and prediction via TIMD (e.g., 23B and 23C) for a rectangular W×W block to be predicted is illustrated. A current block (2303) may be surrounded by an associated TIMD template (2300 and 2301) during TIMD derivation. The tested intra-frame prediction mode may predict the template of the current block based on the decoded reference samples (2302 and 2304) of the template. The added decoded reference samples (e.g., according to one or more examples described herein) are represented as 2304. The (e.g., each) prediction mode derived via TIMD may predict the current block (2303) based on the associated decoded reference samples (2305 and 2306) during prediction via TIMD. The added decoded reference samples according to the first embodiment may be represented as 2306.

[0198] Although features and elements are described above in specific combinations, it will be understood by those of ordinary skill in the art that each feature or element may be used alone or in any combination with other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (sent via a wired or wireless connection) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media (such as built-in hard disks and removable disks), magneto-optical media, and optical media (such as CD-ROM disks and digital versatile disks (DVDs)). A processor associated with software may be used to implement a radio frequency transceiver for a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. A video decoding device comprising a processor, wherein the processor is further configured to: Get the most probable mode (MPM) list associated with the current block; Determine a test list of intra prediction modes from the MPM list; testing a first intra prediction mode, wherein the first intra prediction mode is excluded from the test list or not allowed to be tested due to wide angle intra prediction (WAIP) substitution; generating a prediction for the current block based on the tested intra prediction mode; as well as The current block is decoded using the prediction.

2. The video decoding device according to claim 1, wherein the processor is further configured to: testing a second intra prediction mode, wherein the second intra prediction mode is included in the test list; and The prediction for the current block is generated based on the tested first intra prediction mode and the tested second intra prediction mode. 3 . The video decoding apparatus of claim 2 , wherein the testing of the first intra-prediction mode occurs before the determining of the test list. 4 . The video decoding apparatus of claim 2 , wherein the current block is associated with a first shape, and wherein the first intra-prediction mode is associated with a second shape. 5 . The video decoding apparatus according to claim 4 , wherein the first shape is a rectangle, and wherein the second shape is a square, and wherein lengths of adjacent sides of the first shape are different from each other. 6 . The video decoding apparatus according to claim 4 , wherein the first shape is a square, and wherein the second shape is a rectangle, and wherein lengths of adjacent sides of the second shape are different from each other.

7. The video decoding device according to claim 1, wherein the processor is further configured to: A plurality of intra prediction mode indexes are generated, and wherein the plurality of intra prediction mode indexes are used to generate the prediction for the current block.

8. The video decoding device according to claim 7, wherein the processor is further configured to: Weights of the multiple intra-prediction mode indices are calculated, wherein at least one of the weights is a sum of absolute transform differences (SATD), and wherein the prediction for the current block is further generated based on a subset of intra-prediction mode indices with minimum predicted SATD from the multiple intra-prediction mode indices.

9. The video decoding device of claim 1, wherein the generated prediction is further based on the calculated weights.

10. The video decoding apparatus of claim 9, wherein the calculated weights include a first calculated weight associated with the tested first intra-prediction mode and a second weight associated with the tested second intra-prediction mode. 11 . The video decoding device according to claim 1 , wherein the processor is further configured to add at least one decoded reference sample for the first intra prediction mode.

12. A video encoding device comprising a processor, wherein the processor is further configured to: Get the most probable mode (MPM) list associated with the current block; Determine a test list of intra prediction modes from the MPM list; testing a first intra prediction mode, wherein the first intra prediction mode is excluded from the test list or not allowed to be tested due to wide angle intra prediction (WAIP) substitution; generating a prediction for the current block based on the tested intra prediction mode; as well as The current block is encoded using the prediction.

13. The video decoding device according to claim 12, wherein the processor is further configured to: testing a second intra prediction mode, wherein the second intra prediction mode is included in the test list; and The prediction for the current block is generated based on the tested first intra prediction mode and the tested second intra prediction mode.

14. The video encoding apparatus of claim 13, wherein the testing of the first intra-prediction mode occurs before the determining of the test list.

15. The video encoding apparatus of claim 13, wherein the current block is associated with a first shape, and wherein the first intra-prediction mode is associated with a second shape. 16 . The video encoding apparatus of claim 15 , wherein the first shape is a rectangle, and wherein the second shape is a square, and wherein lengths of adjacent sides of the first shape are different from each other. 17 . The video encoding apparatus of claim 15 , wherein the first shape is a square, and wherein the second shape is a rectangle, and wherein lengths of adjacent sides of the second shape are different from each other.

18. The video encoding device according to claim 12, wherein the processor is further configured to: A plurality of intra prediction mode indexes are generated, and wherein the plurality of intra prediction mode indexes are used to generate the prediction for the current block.

19. The video encoding device according to claim 18, wherein the processor is further configured to: Weights of the multiple intra-prediction mode indices are calculated, wherein at least one of the weights is a sum of absolute transform differences (SATD), and wherein the prediction for the current block is further generated based on a subset of intra-prediction mode indices with minimum predicted SATD from the multiple intra-prediction mode indices.

20. The video encoding device of claim 12, wherein the generated prediction is further based on the calculated weights.

21. The video encoding apparatus of claim 20, wherein the calculated weights include a first calculated weight associated with the tested first intra-prediction mode and a second weight associated with the tested second intra-prediction mode.

22. The video encoding device of claim 12, wherein the processor is further configured to add at least one decoded reference sample for the first intra prediction mode.

23. The apparatus of claims 1 to 22, further comprising a memory operatively connected to the processor.

24. A method for a video decoder, the method further comprising: Get the most probable mode (MPM) list associated with the current block; Determine a test list of intra prediction modes from the MPM list; testing a first intra prediction mode, wherein the first intra prediction mode is excluded from the test list or is not allowed to be tested due to wide angle intra prediction (WAIP) substitution; generating a prediction for the current block based on the tested intra prediction mode; as well as The current block is decoded using the prediction.

25. The method according to claim 24, further comprising: testing a second intra prediction mode, wherein the second intra prediction mode is included in the test list; as well as The prediction for the current block is generated based on the tested first intra prediction mode and the tested second intra prediction mode.

26. The method of claim 25, wherein the testing of the first intra-prediction mode occurs before the determining of the test list.

27. The method of claim 25, wherein the current block is associated with a first shape, and wherein the first intra-prediction mode is associated with a second shape.

28. The method of claim 27, wherein the first shape is a rectangle, and wherein the second shape is a square, and wherein lengths of adjacent sides of the first shape are different from each other.

29. The method of claim 27, wherein the first shape is a square, and wherein the second shape is a rectangle, and wherein lengths of adjacent sides of the second shape are different from each other.

30. The method of claim 24, further comprising: A plurality of intra prediction mode indexes are generated, and wherein the plurality of intra prediction mode indexes are used to generate the prediction for the current block.

31. The method according to claim 30, further comprising: Weights of the multiple intra-prediction mode indices are calculated, wherein at least one of the weights is a sum of absolute transform differences (SATD), and wherein the prediction for the current block is further generated based on a subset of intra-prediction mode indices with minimum predicted SATD from the multiple intra-prediction mode indices.

32. The method of claim 24, wherein the generated predictions are further based on the calculated weights.

33. The method of claim 32, wherein the calculated weights include a first calculated weight associated with the tested first intra-prediction mode and a second weight associated with the tested second intra-prediction mode.

34. The video decoding device of claim 24, the method further comprising adding at least one decoded reference sample for the first intra prediction mode.

35. A method for a video encoder, the method further comprising: Get the most probable mode (MPM) list associated with the current block; Determine a test list of intra prediction modes from the MPM list; testing a first intra prediction mode, wherein the first intra prediction mode is excluded from the test list or is not allowed to be tested due to wide angle intra prediction (WAIP) substitution; generating a prediction for the current block based on the tested intra prediction mode; as well as The current block is encoded using the prediction.

36. The method of claim 35, further comprising: testing a second intra prediction mode, wherein the second intra prediction mode is included in the test list; as well as The prediction for the current block is generated based on the tested first intra prediction mode and the tested second intra prediction mode.

37. The method of claim 36, wherein the testing of the first intra-prediction mode occurs before the determining of the test list.

38. The method of claim 36, wherein the current block is associated with a first shape, and wherein the first intra-prediction mode is associated with a second shape.

39. The method of claim 38, wherein the first shape is a rectangle, and wherein the second shape is a square, and wherein lengths of adjacent sides of the first shape are different from each other.

40. The method of claim 38, wherein the first shape is a square, and wherein the second shape is a rectangle, and wherein lengths of adjacent sides of the second shape are different from each other.

41. The method of claim 35, further comprising: A plurality of intra prediction mode indexes are generated, and wherein the plurality of intra prediction mode indexes are used to generate the prediction for the current block.

42. The method of claim 41, further comprising: Weights of the multiple intra-prediction mode indices are calculated, wherein at least one of the weights is a sum of absolute transform differences (SATD), and wherein the prediction for the current block is further generated based on a subset of intra-prediction mode indices with minimum predicted SATD from the multiple intra-prediction mode indices.

43. The method of claim 35, wherein the generated predictions are further based on the calculated weights.

44. The method of claim 43, wherein the calculated weights include a first calculated weight associated with the tested first intra-prediction mode and a second weight associated with the tested second intra-prediction mode.

45. The method of claim 35, further comprising adding at least one decoded reference sample for the first intra-prediction mode.

46. ​​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 at least one of claims 24 to 45 when executed by a processor.

47. A computer program comprising program code instructions for implementing the steps of the method according to at least one of claims 24 to 45 when executed by a processor.

48. Video data comprising information representing decoded blocks encoded according to one of the methods of any one of claims 35 to 45.

Images