Adaptive interpolation filter for motion compensation

Abstract

A video processing apparatus can include one or more processors configured to determine an interpolation filter length of an interpolation filter associated with a coding unit (CU) based on a size of the CU. The one or more processors can be configured to determine an interpolated reference sample based on the determined interpolation filter length of the interpolation filter and a reference sample of the CU. The one or more processors can be configured to predict the CU based on the interpolated reference sample. For example, if a size of a first CU is greater than a size of a second CU, the one or more processors can be configured to use a shorter interpolation filter for the first CU than for the second CU.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of Provisional U.S. Patent Application No. 62 / 902,089, filed September 18, 2019; Provisional U.S. Patent Application No. 62 / 904,523, filed September 23, 2019; and Provisional U.S. Patent Application No. 62 / 905,867, filed September 25, 2019, the full disclosures of which are incorporated herein by reference. Background Technology

[0003] Video coding systems can be used to compress digital video signals to, for example, reduce the storage and / or transmission bandwidth associated with such signals. Video coding systems can include block-based, wavelet-based, and / or object-based systems. Hybrid block-based video coding systems can be deployed. Summary of the Invention

[0004] Systems, methods, and tools for applying adaptive interpolation filtering during motion compensation are disclosed. The video processing apparatus described herein may include one or more processors configured to determine an interpolation filter length associated with an interpolation filter for a coding unit (CU) based on the size of the CU, determine an interpolation reference sample based on the determined interpolation filter length and a reference sample of the CU, and predict the CU based on the interpolation reference sample. For example, if the size of a first CU is larger than the size of a second CU, one or more processors may use a shorter interpolation filter for the first CU compared to the second CU. Additionally, one or more processors of the video processing apparatus may be configured to select the MV of a CU from a plurality of motion vector (MV) candidates of the CU, determine the MV associated with the reference sample based on the MV of the CU, determine the reference sample based on the MV associated with the reference sample, and perform interpolation using the reference sample and an interpolation filter having the determined interpolation filter length to determine the interpolation reference sample.

[0005] The video processing apparatus described herein may include one or more processors configured to determine the size of the CU and a reference sample of the CU; determine, based on the size of the CU, whether to apply an interpolation filter to the reference sample of the CU; and predict the CU based on the determination of whether to apply the interpolation filter to the reference sample of the CU. The video processing apparatus described herein may include one or more processors configured to determine, based on the size of the CU, that the interpolation filter length of the interpolation filter is 1, and to skip interpolation of the reference sample based on the determination that the interpolation filter length of the interpolation filter is 1, such that the CU is predicted using the reference sample of the CU (e.g., without interpolation).

[0006] The CU described herein may be an affine pattern CU and may include one or more 4×4 sub-blocks. One or more processors of a video processing apparatus may be further configured to determine the MV of the 4×4 sub-blocks in the CU based at least on the motion vector (MV) associated with the CU, and to predict the CU based on the determined MV of the 4×4 sub-blocks of the CU. The length of the interpolation filter as described herein may be indicated by the number of taps associated with the filter. The interpolation filter may be used to determine the value of a reference sample located at a fractional pixel position. Attached Figure Description

[0007] Figure 1A This is a system diagram illustrating an exemplary communication system.

[0008] Figure 1B It shows that it can be used Figure 1A A system diagram of an exemplary wireless transmit / receive unit (WTRU) used within the communication system shown.

[0009] Figure 1C It shows that it can be used Figure 1A The diagram shows an exemplary radio access network (RAN) and an exemplary core network (CN) used within the communication system.

[0010] Figure 1D It shows that it can be used Figure 1A The system diagram shows another exemplary RAN and another exemplary CN used within the communication system shown.

[0011] Figure 2 An exemplary video encoder is shown.

[0012] Figure 3 An example video decoder is shown.

[0013] Figure 4 A block diagram of an example system in which various aspects and examples are implemented is shown.

[0014] Figure 5 Exemplary top and left neighbor blocks are shown that can be used in the combined inter-frame and intra-frame prediction (CIIP) weight derivation.

[0015] Figure 6 Inter-frame prediction based on an exemplary triangular partition is shown.

[0016] Figure 7 An example of single-predictive motion vector selection for Triangle Partitioning Pattern (TPM) is shown.

[0017] Figure 8 Exemplary weights that can be used in a hybrid, such as TPM, are shown.

[0018] Figure 9Examples of using different interpolation filters are shown for sub-blocks inside the TPM edge region and sub-blocks outside the TPM edge region.

[0019] Figure 10 An example of an adaptive interpolation filter for samples associated with different weights is shown (e.g., in TPM mode).

[0020] Figure 11 An exemplary method for performing adaptive interpolation based on CU size is shown.

[0021] Figure 12 An exemplary CIIP mode using planar intra-frame prediction mode and inter-frame prediction mode (e.g., most recent integer MV) is shown. Detailed Implementation

[0022] A detailed description of exemplary embodiments will now be described with reference to the various accompanying drawings. Although this specification provides detailed examples of possible specific implementations, it should be noted that the details are intended to be exemplary and in no way limit the scope of this application.

[0023] Figure 1A This is a schematic diagram illustrating an exemplary communication system 100 that can be implemented using one or more of the disclosed examples. Communication system 100 can be a multiple access system providing content such as voice, data, video, messaging, and broadcasting to multiple wireless users. Communication system 100 enables multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, communication system 100 can 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 Extended OFDM (ZT UW DTS-s OFDM), Unique Word OFDM (UW-OFDM), Resource Block Filtered OFDM, Filter Bank Multicarrier (FBMC), etc.

[0024] like Figure 1AAs 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. However, it should be understood that the disclosed examples can contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of the WTRUs 102a, 102b, 102c, and 102d can be any type of device configured to operate and / or communicate in a wireless environment. As an example, WTRUs 102a, 102b, 102c, and 102d (any of which may be referred to as a “station” and / or “STA”) may be configured to transmit and / or receive wireless signals and may include user equipment (UE), mobile stations, fixed or mobile user units, subscription-based units, pagers, cellular phones, personal digital assistants (PDAs), smartphones, laptops, netbooks, personal computers, wireless sensors, hotspots or Mi-Fi devices, Internet of Things (IoT) devices, watches or other wearable devices, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in industrial and / or automated processing chain environments), consumer electronics devices, devices operating on commercial and / or industrial wireless networks, etc. Any of WTRUs 102a, 102b, 102c, and 102d may be interchangeably referred to as a UE.

[0025] The communication system 100 may also include base station 114a and / or base station 114b. Each of base stations 114a and 114b may be any type of device configured to wirelessly interface with at least one of WTRUs 102a, 102b, 102c, and 102d to facilitate access to one or more communication networks, such as CN106 / 115, Internet 110, and / or other networks 112. As an example, base stations 114a and 114b may be base transceiver stations (BTS), Node Bs, evolved Node Bs, home Node Bs, home evolved Node Bs, gNBs, NR Node Bs, site controllers, access points (APs), wireless routers, etc. Although base stations 114a and 114b are each depicted as a single element, it should be understood that base stations 114a and 114b may include any number of interconnected base stations and / or network elements.

[0026] Base station 114a may be part of RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as base station controllers (BSCs), radio network controllers (RNCs), relay nodes, etc. Base station 114a and / or base station 114b may be configured to transmit and / or receive radio signals on one or more carrier frequencies (which may be referred to as cells (not shown)). These frequencies may be in licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage of radio services to a specific geographic area, which may be relatively fixed or changeable over time. A cell may be further divided into cell sectors. For example, the cell associated with base station 114a may be divided into three sectors. Therefore, in this example, base station 114a may include three transceivers, i.e., one transceiver per sector of the cell. In this example, 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 transmit and / or receive signals in desired spatial directions.

[0027] Base stations 114a and 114b can communicate with one or more of WTRUs 102a, 102b, 102c, and 102d via air interface 116, which can be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). Any suitable radio access technology (RAT) can be used to establish air interface 116.

[0028] 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, base stations 114a and WTRUs 102a, 102b, and 102c in RAN 104 / 113 may implement radio technologies such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may use Wideband CDMA (WCDMA) to establish air interfaces 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).

[0029] In the example, base station 114a and WTRUs 102a, 102b, 102c can implement radio technologies such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which can use Long Term Evolution (LTE) and / or Advanced LTE (LTE-A) and / or Advanced LTE Pro (LTE-A Pro) to establish air interface 116.

[0030] In the example, base station 114a and WTRUs 102a, 102b, 102c can implement radio technologies such as NR radio access, which can use New Radio (NR) to establish air interface 116.

[0031] In the example, base station 114a and WTRUs 102a, 102b, and 102c can implement multiple radio access technologies. For example, base station 114a and WTRUs 102a, 102b, and 102c can, for instance, use a dual connectivity (DC) principle to implement both LTE and NR radio access together. Therefore, the air interface used by WTRUs 102a, 102b, and 102c can be characterized by multiple types of radio access technologies and / or transmissions sent to / from multiple types of base stations (e.g., eNBs and gNBs).

[0032] In several examples, base station 114a and WTRUs 102a, 102b, and 102c can implement radio technologies such as IEEE 802.11 (i.e., Wi-Fi), IEEE 802.16 (i.e., WiMAX), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Provisional Standard 2000 (IS-2000), Provisional Standard 95 (IS-95), Provisional Standard 856 (IS-856), Global System for Mobile Communications (GSM), GSM Enhanced Data Rate Evolution (EDGE), and GSM EDGE (GERAN).

[0033] Figure 1ABase station 114b can be, for example, a wireless router, a home node B, a home evolution node B, or an access point, and can utilize any suitable RAT to facilitate wireless connectivity in local areas such as commercial locations, homes, vehicles, campuses, industrial facilities, air corridors (e.g., for use by drones), roads, etc. In the example, base station 114b and WTRUs 102c and 102d can implement radio technologies such as IEEE 802.11 to establish a wireless local area network (WLAN). In the example, base station 114b and WTRUs 102c and 102d can implement radio technologies such as IEEE 802.15 to establish a wireless personal area network (WPAN). In the example, base station 114b and WTRUs 102c and 102d can utilize cellular-based RATs (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish picocells or femtocells. 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.

[0034] RAN 104 / 113 can communicate with CN 106 / 115, which can be any type of network configured to provide voice, data, application, and / or Voice over Internet Protocol (VoIP) services to one or more of WTRU102a, 102b, 102c, and 102d. Data can 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. CN 106 / 115 can provide call control, billing services, location-based services, prepaid calling, internet connectivity, video distribution, etc., and / or perform advanced security functions such as user authentication. Although not explicitly stated... Figure 1A As shown, but it should be understood that RAN 104 / 113 and / or CN 106 / 115 can communicate directly or indirectly with other RANs that use the same RAT as RAN 104 / 113 or a different RAT. For example, in addition to being connected to RAN 104 / 113 which can utilize NR radio technology, CN 106 / 115 can also communicate with another RAN (not shown) that uses GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or WiFi radio technology.

[0035] CN 106 / 115 may also act as a gateway for WTRU 102a, 102b, 102c, 102d to access PSTN 108, Internet 110, and / or other networks 112. PSTN 108 may include a circuit-switched telephone network providing Common Old-Style Telephone Service (POTS). Internet 110 may include a global system of interconnected computer networks and devices using common communication protocols such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and / or Internet Protocol (IP) from the TCP / IP Internet Protocol suite. Network 112 may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, network 112 may include another CN connected to one or more RANs, which may use the same RAT as RAN 104 / 113 or a different RAT.

[0036] Some or all of the WTRUs 102a, 102b, 102c, and 102d in the communication system 100 may include multi-mode capabilities (e.g., WTRUs 102a, 102b, 102c, and 102d may include multiple transceivers for communicating with different wireless networks via different wireless links). For example, Figure 1A The WTRU 102c shown can be configured to communicate with a base station 114a that can employ cellular-based radio technology and with a base station 114b that can employ IEEE 802 radio technology.

[0037] Figure 1B This is a system diagram illustrating an exemplary WTRU 102. (See diagram below.) Figure 1B As shown, WTRU 102 may include a processor 118, a transceiver 120, a transmitting / receiving element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power supply 134, a Global Positioning System (GPS) chipset 136, and / or other peripheral devices 138, etc. It should be understood that WTRU 102 may include any sub-combination of the foregoing elements.

[0038] Processor 118 can be a general-purpose processor, a special-purpose processor, a conventional processor, a digital signal processor (DSP), multiple 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. Processor 118 can perform signal encoding, data processing, power control, input / output processing, and / or any other functions that enable WTRU 102 to operate in a wireless environment. Processor 118 can be coupled to transceiver 120, which can be coupled to transmitting / receiving element 122. Although Figure 1BThe processor 118 and transceiver 120 are depicted as separate components, but it should be understood that the processor 118 and transceiver 120 may be integrated together in an electronic package or chip.

[0039] Transmitting / receiving element 122 may be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) via air interface 116. For example, in one example, transmitting / receiving element 122 may be an antenna configured to transmit and / or receive RF signals. In another example, transmitting / receiving element 122 may be a transmitter / detector configured to transmit and / or receive signals such as IR, UV, or visible light signals. In yet another example, transmitting / receiving element 122 may be configured to transmit and / or receive both RF and optical signals. It should be understood that transmitting / receiving element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0040] Although the transmitting / receiving element 122 is in Figure 1B While depicted as a single element, WTRU 102 may include any number of transmitting / receiving elements 122. More specifically, WTRU 102 may employ MIMO technology. Thus, in this example, WTRU 102 may include two or more transmitting / receiving elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals via air interface 116.

[0041] Transceiver 120 can be configured to modulate signals transmitted by transmitting / receiving element 122 and demodulate signals received by transmitting / receiving element 122. As noted above, WTRU 102 may have multi-mode capability. Therefore, transceiver 120 may include multiple transceivers to enable WTRU 102 to communicate via various RATs (such as NR and IEEE 802.11).

[0042] The processor 118 of WTRU 102 may be coupled to a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) unit or an organic light-emitting diode (OLED) display unit) and may receive user input data therefrom. The processor 118 may also output user data to the speaker / microphone 124, keypad 126, and / or display / touchpad 128. Furthermore, the processor 118 may access information from any type of suitable memory (such as non-removable memory 130 and / or removable memory 132) and store data in any type of suitable memory. Non-removable memory 130 may include random access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. Removable memory 132 may include a user identity module (SIM) card, memory stick, secure digital storage (SD) card, etc. In several examples, the processor 118 may access information from memory not physically located on WTRU 102 (such as on a server or home computer (not shown)) and store data in that memory.

[0043] The processor 118 may receive power from the power supply 134 and may be configured to distribute and / or control power to other components in the WTRU 102. The power supply 134 may be any suitable device for powering the WTRU 102. For example, the power supply 134 may include one or more dry cell battery packs (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0044] The processor 118 may also be coupled to a GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) about the current location of the WTRU 102. In addition to or instead of the information from the GPS chipset 136, the WTRU 102 may receive location information from base stations (e.g., base stations 114a, 114b) via air interface 116 and / or determine its location based on the timing of signals received from two or more nearby base stations. It should be understood that the WTRU 102 may acquire location information using any suitable location determination method.

[0045] The processor 118 may also be coupled to other peripheral devices 138, which may include one or more software and / or hardware modules providing additional features, functions, and / or wired or wireless connectivity. For example, peripheral device 138 may include an accelerometer, electronic compass, satellite transceiver, digital camera (for photos and / or video), Universal Serial Bus (USB) port, vibration device, television transceiver, hands-free headset, etc. Modules, FM radio units, digital music players, media players, video game player modules, internet browsers, virtual reality and / or augmented reality (VR / AR) devices, activity trackers, etc. Peripheral devices 138 may include one or more sensors, which may be one or more of the following: gyroscopes, accelerometers, Hall effect sensors, magnetometers, orientation sensors, proximity sensors, temperature sensors, time sensors; geolocation sensors; altimeters, light sensors, touch sensors, magnetometers, barometers, gesture sensors, biometric sensors, and / or humidity sensors.

[0046] WTRU 102 may include a full-duplex radio for which the 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 139 for reducing and / or substantially eliminating self-interference through signal processing via hardware (e.g., a choke) or via a processor (e.g., a separate processor (not shown) or via processor 118). In this example, WTRU 102 may include a full-duplex radio for which the 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.

[0047] Figure 1C This is a system diagram illustrating exemplary RAN 104 and CN 106. As described above, RAN 104 can communicate with WTRUs 102a, 102b, and 102c via air interface 116 using E-UTRA radio technology. RAN 104 can also communicate with CN 106.

[0048] RAN 104 may include evolved Node Bs 160a, 160b, and 160c; however, it should be understood that RAN 104 may include any number of evolved Node Bs. Each evolved Node B 160a, 160b, and 160c may include one or more transceivers for communicating with WTRUs 102a, 102b, and 102c via air interface 116. In this example, evolved Node Bs 160a, 160b, and 160c may implement MIMO technology. Therefore, evolved Node B 160a may, for example, use multiple antennas to transmit radio signals to and / or receive radio signals from WTRU 102a.

[0049] Each of the evolved nodes B 160a, 160b, and 160c can be associated with a specific cell (not shown) and can be configured to handle radio resource management decisions, handover decisions, and user scheduling in the UL and / or DL, etc. Figure 1C As shown, evolution nodes B 160a, 160b, and 160c can communicate with each other via the X2 interface.

[0050] Figure 1C The CN 106 shown may include a Mobility Management Entity (MME) 162, a Serving Gateway (SGW) 164, and a Packet Data Network (PDN) Gateway (or PGW) 166. Although each of the foregoing elements is depicted as 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.

[0051] The MME 162 can connect to each of the evolved nodes B 162a, 162b, and 162c in RAN 104 via the S1 interface and can be used as a control node. For example, the MME 162 can be responsible for authenticating users of WTRUs 102a, 102b, and 102c, bearer activation / deactivation, selecting a specific serving gateway during the initial attachment of WTRUs 102a, 102b, and 102c, etc. The MME 162 can provide control plane functions for handover between RAN 104 and other RANs (not shown) employing other radio technologies such as GSM and / or WCDMA.

[0052] The SGW 164 can connect to each of the evolved Nodes B 160a, 160b, and 160c in RAN 104 via the S1 interface. The SGW 164 typically routes and forwards user data packets to and from WTRUs 102a, 102b, and 102c. The SGW 164 can perform other functions such as anchoring the user plane during inter-evolved Node B handovers, triggering paging when DL data is available for WTRUs 102a, 102b, and 102c, and managing and storing the context of WTRUs 102a, 102b, and 102c.

[0053] SGW 164 can be connected to PGW 166, which provides WTRU 102a, 102b, 102c with access to packet-switched networks (such as Internet 110) to facilitate communication between WTRU 102a, 102b, 102c and IP-enabled devices.

[0054] CN 106 can facilitate communication with other networks. For example, CN 106 can provide WTRUs 102a, 102b, and 102c with access to a circuit-switched network (such as PSTN 108) to facilitate communication between WTRUs 102a, 102b, and 102c and conventional landline communication equipment. For example, CN 106 may include an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between CN 106 and PSTN 108, or be able to communicate with such an IP gateway. Additionally, CN 106 can provide WTRUs 102a, 102b, and 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0055] Despite WTRU in Figures 1A to 1D While described as a wireless terminal, it is conceivable that, in some examples, such a terminal may (e.g., temporarily or permanently) use a wired communication interface with a communication network.

[0056] In several examples, other network 112 could be a WLAN.

[0057] A WLAN in Infrastructure Basic Services Set (BSS) mode may have an access point (AP) for the BSS and one or more sites (STAs) 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 out of the BSS. Traffic originating outside the BSS and destined for a STA can reach and be delivered to the STA via the AP. Traffic originating from a STA and destined for a destination outside the BSS can be sent to the AP for delivery to the appropriate destination. Traffic between STAs within the BSS can be sent via the AP, for example, where a source STA can send traffic to the AP, and the AP can deliver the traffic to the destination STA. Traffic between STAs within the BSS can be considered and / or referred to as point-to-point traffic. Point-to-point traffic can be sent between source and destination STAs (e.g., directly between them) using Direct Link Establishment (DLS). In several examples, the DLS may use 802.11e DLS or 802.11z Tunneled DLS (TDLS). WLANs using the Standalone BSS (IBSS) mode may not have an access point (AP), and STAs within the IBSS or using the IBSS (e.g., all STAs) can communicate directly with each other. The IBSS communication mode may sometimes be referred to as the "ad-hoc" communication mode in this document.

[0058] When operating in 802.11ac infrastructure mode or a similar mode, the AP can transmit beacons on a fixed channel, such as the primary channel. The primary channel can be of fixed width (e.g., a 20 MHz bandwidth) or dynamically set via signaling. The primary channel can be the operating channel of the BSS and can be used by the STA to establish a connection with the AP. In several examples, Carrier Sense Multiple Access / Collision Avoidance (CSMA / CA) can be implemented, for example, in an 802.11 system. For CSMA / CA, each STA (including the AP) can listen on the primary channel. If the primary channel is listened to / detected and / or determined to be busy by a particular STA, that STA can back off. A single STA (e.g., only one station) can transmit in a given BSS at any given time.

[0059] High-throughput (HT) STAs can communicate using a 40MHz wide channel, for example, by combining a primary 20MHz channel with adjacent or non-adjacent 20MHz channels to form a 40MHz wide channel.

[0060] The Very High Throughput (VHT) STA supports channels with widths of 20MHz, 40MHz, 80MHz, and / or 160MHz. 40MHz and / or 80MHz channels can be formed by combining consecutive 20MHz channels. A 160MHz channel can be formed by combining eight consecutive 20MHz channels, or by combining two non-consecutive 80MHz channels (this can be referred to as an 80+80 configuration). For the 80+80 configuration, after channel coding, data can be split into two streams by a segment parser. Each stream can be processed individually using Inverse Fast Fourier Transform (IFFT) and time-domain processing. These streams can be mapped to two 80MHz channels, and data can be transmitted via the transmitting STA. At the receiver of the receiving STA, the operations described above for the 80+80 configuration can be reversed, and the combined data can be sent to Media Access Control (MAC).

[0061] 802.11af and 802.11ah support operating modes below 1 GHz. Compared to those used in 802.11n and 802.11ac, 802.11af and 802.11ah reduce channel operating bandwidth and carrier. 802.11af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV white space (TVWS) spectrum, while 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to examples, 802.11ah may support instrument-type control / machine-type communication, such as MTC devices in macro coverage areas. MTC devices may have certain capabilities, such as limited capabilities, including support (e.g., only support) certain bandwidths and / or limited bandwidths. MTC devices may include batteries with battery life exceeding a threshold (e.g., to maintain a very long battery life).

[0062] WLAN systems supporting multiple channels, as well as channel bandwidths such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include channels that can be designated as primary channels. A primary channel can have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel can be set and / or limited by STAs operating in the BSS (each supporting a minimum bandwidth operating mode). In the 802.11ah example, for STAs supporting (e.g., only supporting) a 1MHz mode (e.g., MTC type devices), the primary channel can 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 Sense and / or Network Allocation Vector (NAV) settings can depend on the status of the primary channel. If the primary channel is busy, for example, because an STA (supporting only the 1MHz operating mode) is transmitting to the AP, the entire available band can be considered busy even if most of the band remains idle and potentially available.

[0063] In the United States, the available frequency bands for 802.11ah are 902MHz to 928MHz. In South Korea, the available frequency bands are 917.5MHz to 923.5MHz. In Japan, the available frequency bands are 916.5MHz to 927.5MHz. The total available bandwidth for 802.11ah ranges from 6MHz to 26MHz, depending on the country code.

[0064] Figure 1D This is a system diagram illustrating exemplary RAN 113 and CN 115. As noted above, RAN 113 can communicate with WTRUs 102a, 102b, and 102c via air interface 116 using NR radio technology. RAN 113 can also communicate with CN 115.

[0065] RAN 113 may include gNBs 180a, 180b, and 180c; however, it should be understood that RAN 113 may include any number of gNBs. Each of gNBs 180a, 180b, and 180c may include one or more transceivers for communication with WTRUs 102a, 102b, and 102c via air interface 116. In this example, gNBs 180a, 180b, and 180c may implement MIMO technology. For example, gNBs 180a and 180b may utilize beamforming to transmit signals to and / or receive signals from gNBs 180a, 180b, and 180c. Therefore, gNB 180a may, for example, use multiple antennas to transmit radio signals to and / or receive radio signals from WTRU 102a. In this example, gNBs 180a, 180b, and 180c may implement carrier aggregation technology. For example, gNB 180a can 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 this example, gNBs 180a, 180b, and 180c can implement Cooperative Multipoint (CoMP) technology. For example, WTRU 102a can receive cooperative transmissions from gNBs 180a and 180b (and / or gNB 180c).

[0066] WTRUs 102a, 102b, and 102c can communicate with gNBs 180a, 180b, and 180c using transmissions associated with scalable parameter sets. For example, OFDM symbol spacing and / or OFDM subcarrier spacing can vary depending on different transmissions, different cells, and / or different portions of the radio transmission spectrum. WTRUs 102a, 102b, and 102c can communicate with gNBs 180a, 180b, and 180c using subframes or transmission time intervals (TTIs) of various or scalable lengths (e.g., containing different numbers of OFDM symbols and / or continuously varying absolute time lengths).

[0067] gNBs 180a, 180b, and 180c can be configured to communicate with WTRUs 102a, 102b, and 102c in standalone and / or non-standalone configurations. In standalone configuration, WTRUs 102a, 102b, and 102c can communicate with gNBs 180a, 180b, and 180c without accessing other RANs (e.g., evolved Node Bs 160a, 160b, and 160c). In standalone configuration, WTRUs 102a, 102b, and 102c can use one or more of gNBs 180a, 180b, and 180c as mobility anchors. In standalone configuration, WTRUs 102a, 102b, and 102c can communicate with gNBs 180a, 180b, and 180c using signals in unlicensed frequency bands. In a non-standalone configuration, WTRUs 102a, 102b, and 102c can communicate or connect to gNBs 180a, 180b, and 180c, and also communicate or connect to other RANs (such as eNode-B160a, 160b, and 160c). For example, WTRUs 102a, 102b, and 102c can implement DC principles to communicate substantially simultaneously with one or more gNBs 180a, 180b, and 180c and one or more evolved Node Bs 160a, 160b, and 160c. In a non-standalone configuration, evolved Node Bs 160a, 160b, and 160c can be used as mobility anchors for WTRUs 102a, 102b, and 102c, and gNBs 180a, 180b, and 180c can provide additional coverage and / or throughput for serving WTRUs 102a, 102b, and 102c.

[0068] Each of gNBs 180a, 180b, and 180c can be associated with a specific cell (not shown) and can be configured to handle radio resource management decisions, handover decisions, user scheduling in UL and / or DL, network slicing support, dual connectivity, interoperability between NR and E-UTRA, routing of user plane data to User Plane Functions (UPF) 184a and 184b, routing of control plane information to Access and Mobility Management Functions (AMF) 182a and 182b, etc. Figure 1D As shown, gNB180a, 180b, and 180c can communicate with each other via the Xn interface.

[0069] Figure 1DThe CN 115 shown may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 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.

[0070] AMF 182a and 182b can connect to one or more of gNBs 180a, 180b, and 180c via the N2 interface in RAN 113 and can be used as control nodes. For example, AMF 182a and 182b can be responsible for authenticating users of WTRU 102a, 102b, and 102c, supporting network slicing (e.g., handling different PDU sessions with different requirements), selecting specific SMF 183a and 183b, managing registration areas, terminating NAS signaling, mobility management, etc. AMF 182a and 182b can use network slicing to customize CN support for WTRU 102a, 102b, and 102c based on the type of service used by WTRU 102a, 102b, and 102c. For example, different network slices can be established for different use cases, such as services that rely on Ultra-Reliable Low Latency (URLLC) access, services that rely on Enhanced Mobile Broadband (eMBB) access, and services for Machine Type Communication (MTC) access. The AMF162 can provide control plane functions for handover between 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.

[0071] SMFs 183a and 183b can connect to AMFs 182a and 182b in CN 115 via the N11 interface. SMFs 183a and 183b can also connect to UPFs 184a and 184b in CN 115 via the N4 interface. SMFs 183a and 183b can select and control UPFs 184a and 184b, and configure traffic routing through UPFs 184a and 184b. SMFs 183a and 183b can perform other functions, such as managing and allocating UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, and providing downlink data notifications. PDU session types can be IP-based, non-IP-based, Ethernet-based, etc.

[0072] UPF 184a and 184b can connect via the N3 interface to one or more of the gNBs 180a, 180b, and 180c in RAN 113. These gNBs can provide WTRU 102a, 102b, and 102c with access to packet-switched networks (such as Internet 110) to facilitate communication between WTRU 102a, 102b, 102c and IP-enabled devices. UPF 184 and 184b can perform other functions such as routing and forwarding packets, enforcing user plane policies, supporting multihomed PDU sessions, handling user plane QoS, buffering downlink packets, and providing mobility anchoring.

[0073] CN 115 may facilitate communication with other networks. For example, CN 115 may include an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between CN115 and PSTN 108, or may communicate with such an IP gateway. Additionally, CN115 may provide WTRUs 102a, 102b, and 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers. In this example, WTRUs 102a, 102b, and 102c may be connected to DN185a and 185b via UPF 184a and 184b through the N3 interface to UPF 184a and 184b and the N6 interface between UPF 184a and 184b and local data networks (DNs) 185a and 185b.

[0074] Given Figures 1A to 1D as well as Figures 1A to 1D The corresponding descriptions herein refer to one or more of the functions described below, which may be performed by one or more emulation devices (not shown): WTRU102a-102d, base station 114a-114b, evolved Node B 160a-160c, MME 162, SGW 164, PGW 166, gNB 180a-180c, AMF182a-182b, UPF 184a-184b, SMF 183a-183b, DN 185a-185b, and / or any other devices described herein. An emulation device may be one or more devices configured to mimic one or more of the functions described herein. For example, an emulation device may be used to test other devices and / or simulate network and / or WTRU functions.

[0075] Simulation devices can be designed to perform one or more tests on other devices in laboratory and / or carrier network environments. For example, the one or more simulation devices may perform one or more or all functions while being fully or partially implemented and / or deployed as part of a wired and / or wireless communication network to test other devices within the communication network. The one or more simulation devices may perform one or more or all functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. Simulation devices may be directly coupled to another device for testing purposes and / or may use over-the-air wireless communication to perform tests.

[0076] The one or more emulation devices may perform one or more (including all) functions without being implemented / deployed as part of a wired and / or wireless communication network. For example, the emulation devices may be used in test scenarios within a test laboratory and / or non-deployed (e.g., testing) wired and / or wireless communication networks to perform testing of one or more components. The one or more emulation devices may be test equipment. Direct RF coupling and / or wireless communication via RF circuitry (e.g., which may include one or more antennas) may be used by the emulation devices to transmit and / or receive data.

[0077] This application describes multiple aspects, including tools, features, examples, models, methods, etc. Many of these aspects are described in a particular manner, and are generally described in a way that may sound restrictive, at least to illustrate individual characteristics. However, this is for clarity and does not limit the application or scope of these aspects. In fact, all the different aspects can be combined and interchanged to provide further aspects. Furthermore, these aspects can also be combined and interchanged with aspects described in previous filings.

[0078] The aspects described and envisioned in this patent application can be implemented in many different forms. Figures 5 to 12 Some examples can be provided, but other examples are envisioned, and Figures 5 to 12 The discussion does not limit the breadth of implementations. At least one of these aspects generally relates to video encoding and decoding, and at least one other aspect generally relates to transmitting a bitstream generated or encoded. These and other aspects can be implemented as methods, apparatus, computer-readable storage media having instructions stored thereon for encoding or decoding video data according to any of the methods, and / or computer-readable storage media having a bitstream generated according to any of the methods stored thereon.

[0079] In this application, the terms "reconstruction" and "decoding" are used interchangeably, as are the terms "pixel" and "sample," and the terms "image," "picture," and "frame." Generally, but not necessarily, the term "reconstruction" is used at the encoding end, while "decoding" is used at the decoding end.

[0080] This document describes various methods, and each method includes one or more steps or actions for implementing the method. Unless the correct operation of the method requires a specific order of steps or actions, the order and / or purpose of specific steps and / or actions may be modified or combined. Additionally, in various examples, terms such as "first," "second," etc., may be used to modify elements, components, steps, operations, etc., such as "first decoding" and "second decoding." Unless specifically required, the use of such terms does not imply a modification of the order of operations. Therefore, in this example, the first decoding does not need to be performed before the second decoding and may occur, for example, before, during, or in overlapping time periods of the second decoding.

[0081] The various methods and other aspects described in this application can be used to modify modules (e.g., decoding modules) of the video encoder 200 and decoder 300, such as... Figure 2 and Figure 3 As shown. Furthermore, aspects of the invention are not limited to VVC or HEVC, and can be applied to, for example, other standards and recommendations (whether pre-existing or future-developed) and any extensions of such standards and recommendations (including VVC and HEVC). Unless otherwise specified or technically excluded, the aspects described in this application may be used alone or in combination.

[0082] Various values ​​are used in this application, such as filters being 2-tap, 4-tap, 6-tap, or 8-tap filters, sub-block sizes being 4×4, and the maximum width and / or height of the maximum CU size used for inter-frame prediction being at most 128, etc. Specific values ​​are for illustrative purposes, and the aspects described are not limited to these specific values.

[0083] Figure 2 Encoder 200 is shown. Variations of this encoder 200 are envisioned, but for clarity, encoder 200 is described below without describing all anticipated variations.

[0084] Before encoding, the video sequence may undergo pre-coding (201), for example, by applying color transformations to the input color image (e.g., a conversion from RGB 4:4:4 to YCbCr 4:2:0), or by performing remapping of the input image components to obtain a more resilient signal distribution to compression (e.g., histogram equalization using one of the color components). Metadata may be associated with pre-processing and appended to the bitstream.

[0085] In encoder 200, the image is encoded by encoder elements as described below. The image to be encoded is partitioned (202) and processed in units such as CUs. For example, each unit is encoded using either an intra-frame mode or an inter-frame mode. When a unit is encoded in intra-frame mode, it performs intra-frame prediction (260). In inter-frame mode, motion estimation (275) and compensation (270) are performed. The encoder determines (205) which of the intra-frame mode or inter-frame mode is used to encode the unit and indicates the intra-frame / inter-frame decision by, for example, a prediction mode label. For example, the prediction residual is calculated by subtracting (210) the prediction block from the original image block.

[0086] The predicted residual is then transformed (225) and quantized (230). The quantized transform coefficients, motion vectors, and other syntax elements are entropy encoded (245) to output a bitstream. The encoder can skip the transform and apply quantization directly to the untransformed residual signal. The encoder can bypass both the transform and quantization, i.e., encode the residual directly without applying the transform or quantization process.

[0087] 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 decoded prediction residual and the prediction block are combined (255) to reconstruct the image block. A loop filter (265) is applied to the reconstructed image to perform, for example, unblocking / SAO (sample adaptive offset) filtering to reduce coding artifacts. The filtered image is stored in a reference image buffer (280).

[0088] Figure 3 A block diagram of a video decoder 300 is shown. In the exemplary decoder 300, the bitstream is decoded by decoder elements, as described below. The video decoder 300 generally performs operations similar to... Figure 2 The encoding process is the reverse of the decoding process. Encoder 200 may also perform video decoding as part of the encoding of video data. For example, encoder 200 may perform one or more video decoding steps as presented herein. The encoder may, for example, reconstruct the decoded image to maintain synchronization with the decoder relative to one or more of the following: a reference picture, entropy coding context, and other decoder-related state variables.

[0089] Specifically, the decoder's input includes a video bitstream, which can be generated by the video encoder 200. First, entropy decoding (330) is performed on the bitstream to obtain transform coefficients, motion vectors, and other encoded information. Image partitioning information indicates how the image should be partitioned. Therefore, the decoder can partition (335) the image based on the decoded image partitioning information. The transform coefficients are dequantized (340) and inverse transformed (350) to decode the prediction residuals. The decoded prediction residuals and prediction blocks are combined (355) to reconstruct the image blocks. Prediction blocks (370) can be obtained from intra-frame prediction (360) or motion-compensated prediction (i.e., inter-frame prediction) (375). A loop filter (365) is applied to the reconstructed image. The filtered image is stored in a reference image buffer (380).

[0090] The decoded image can also undergo post-decoding processing (385), such as inverse color transformation (e.g., conversion from YCbCr 4:2:0 to RGB 4:4:4) or inverse remapping, which is the inverse of the remapping process performed in the pre-encoding process (201). Post-decoding processing can utilize metadata derived in the pre-encoding process and signaled in the bitstream.

[0091] Figure 4 A block diagram illustrating an example of a system implementing various aspects and examples is shown. System 400 may be embodied as a device including the various components described below and configured to perform one or more aspects described in this document. Examples of such devices include, but are not limited to, various electronic devices such as personal computers, laptop computers, smartphones, tablet computers, digital multimedia set-top boxes, digital television receivers, personal video recording systems, connected home appliances, and servers. Elements of system 400 may be embodied individually or in combination in a single integrated circuit (IC), multiple ICs, and / or discrete components. For example, in at least one example, the processing and encoder / decoder elements of system 400 are distributed across 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 and / or output ports. In various examples, system 400 is configured to implement one or more aspects of the aspects described in this document.

[0092] System 400 includes at least one processor 410 configured to execute instructions loaded thereon for implementing various aspects, such as those described in this document. Processor 410 may include embedded memory, input / output interfaces, and various other circuitry known in the art. System 400 includes at least one memory 420 (e.g., a volatile memory device and / or a non-volatile memory device). System 400 includes a storage device 440 that may include non-volatile memory and / or volatile memory, including but not limited to electrically erasable programmable read-only memory (EEPROM), read-only memory (ROM), programmable read-only memory (PROM), random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), flash memory, disk drives, and / or optical disk drives. As a non-limiting example, storage device 440 may include internal storage devices, attached storage devices (including removable and non-removable storage devices), and / or network-accessible storage devices.

[0093] System 400 includes an encoder / decoder module 430 configured to, for example, process data to provide encoded 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 can be included in a device to perform encoding and / or decoding functions. It is well known that a device may include one or both of an encoding module and a decoding module. Furthermore, the encoder / decoder module 430 may be implemented as a standalone element of system 400, or may be incorporated within processor 410 as a combination of hardware and software known to those skilled in the art.

[0094] Program code to be loaded onto processor 410 or encoder / decoder 430 to execute the various aspects described in this document may be stored in storage device 440 and subsequently loaded onto memory 420 for execution by processor 410. According to various examples, one or more of processor 410, memory 420, storage device 440, and encoder / decoder module 430 may store one or more items of various types during the execution of the processes described in this document. Such stored items may include, but are not limited to, input video, decoded or partially decoded video, bitstreams, matrices, variables, and intermediate or final results of processing equations, formulas, operations, and operational logic.

[0095] In some examples, the memory within processor 410 and / or encoder / decoder module 430 is used to store instructions and provide working memory for processing required during encoding or decoding. However, in other examples, memory external to the processing device (e.g., processor 410 or encoder / decoder module 430) is used for one or more of these functions. The external memory can be memory 420 and / or storage device 440, such as volatile memory and / or non-volatile flash memory. In several examples, external non-volatile flash memory is used to store, for example, the operating system of a television. In at least one example, fast external dynamic volatile memory such as RAM is used as working memory for video encoding and decoding operations, such as MPEG-2 (MPEG stands for Moving Picture Experts Group, MPEG-2 is also known as ISO / IEC 13818, and 13818-1 is also known as H.222, and 13818-2 is also known as H.262), HEVC (HEVC stands for High Efficiency Video Coding, also known as H.265 and MPEG-H Part 2) or VVC (Universal Video Coding, a new standard developed by the Joint Video Experts Group (JVET)).

[0096] Inputs to the components of system 400 may be provided by various input devices as shown in box 4430. Such input devices include, but are not limited to: (i) a radio frequency (RF) section that receives, for example, RF signals transmitted over the air by a broadcaster; (ii) component (COMP) input terminals (or a set of COMP input terminals); (iii) universal serial bus (USB) input terminals; and / or (iv) high-definition multimedia interface (HDMI) input terminals. Figure 4 Other examples not shown include composite video.

[0097] In various examples, the input device of block 4430 has associated corresponding input processing elements as known in the art. For example, the RF section may be associated with elements suitable for: (i) selecting a desired frequency (also known as selecting a signal, or limiting a signal band to a band), (ii) downconverting the selected signal, (iii) band-limiting it again to a narrower band to select (e.g.,) a signal band that may be referred to as a channel in some examples, (iv) demodulating the downconverted and band-limited signal, (v) performing error correction, and (vi) demultiplexing to select the desired data packet stream. The RF section of various examples includes one or more elements for performing these functions, such as frequency selectors, signal selectors, band limiters, channel selectors, filters, downconverters, demodulators, error correctors, and demultiplexers. The RF section may include tuners that perform various functions among these functions, such as downconverting received signals to a lower frequency (e.g., intermediate frequency or near-baseband frequency) or to baseband. In one set-top box example, the RF section and its associated input processing elements receive RF signals transmitted via a wired (e.g., cable) medium and perform frequency selection by filtering, down-converting, and re-filtering to the desired frequency band. Various examples rearrange the order of the above (and other) elements, remove some of these elements, and / or add other elements that perform similar or different functions. Adding elements may include inserting elements between existing elements, such as inserting amplifiers and analog-to-digital converters. In various examples, the RF section includes an antenna.

[0098] Furthermore, USB and / or HDMI terminals may include corresponding interface processors for connecting system 400 to other electronic devices across 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, within a separate input processing IC or within processor 410. Similarly, aspects of USB or HDMI interface processing may be implemented as needed, either within a separate interface IC or within processor 410. The demodulated, error-corrected, and demultiplexed stream is provided to various processing elements, including, for example, processor 410 and encoder / decoder 430, which operate in conjunction with memory and storage elements to process the data stream as needed for presentation on the output device.

[0099] Various components of system 400 can be housed within an integrated housing. Within the integrated housing, various components can be interconnected and transmit data therebetween using a suitable connection arrangement 4440 (e.g., internal buses as known in the art, including inter-IC (I2C) buses, wiring, and printed circuit boards).

[0100] System 400 includes a communication interface 450 capable of communicating with other devices via a communication channel 460. The communication interface 450 may include, but is not limited to, a transceiver configured to transmit and receive data via the communication channel 460. The communication interface 450 may include, but is not limited to, a modem or network interface card (NIC), and the communication channel 460 may be implemented, for example, within a wired and / or wireless medium.

[0101] In various examples, wireless networks such as Wi-Fi networks, such as IEEE 802.11 (IEEE refers to the Institute of Electrical and Electronics Engineers), are used to stream or otherwise provide data to system 400. In these examples, the Wi-Fi signal is received via a communication channel 460 and a communication interface 450 suitable for Wi-Fi communication. The communication channel 460 in 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-platform communications. Other examples use a set-top box to provide streaming data to system 400, delivering data via an HDMI connection of input block 4430. Still other examples use an RF connection of input block 4430 to provide streaming data to system 400. As mentioned 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 Bluetooth networks.

[0102] System 400 can provide output signals to various output devices, including a display 4400, a speaker 4410, and other peripheral devices 4420. Various examples of the display 4400 include one or more of, for example, a touchscreen display, an organic light-emitting diode (OLED) display, a curved display, and / or a foldable display. The display 4400 can be used in televisions, tablets, laptops, cellular phones (mobile phones), or other devices. The display 4400 can also be integrated with other components (e.g., as in a smartphone) or standalone (e.g., an external monitor for a laptop computer). In various examples, other peripheral devices 4420 include one or more of a standalone digital video disc (or digital universal disc) (DVR, for both terms), a disc player, a stereo system, and / or a lighting system. Various examples use one or more peripheral devices 4420 that provide functionality based on the output of system 400. For example, a disc player performs the function of playing the output of system 400.

[0103] In various examples, signaling such as AV.Link, Consumer Electronics Control (CEC), or other communication protocols capable of device-to-device control with or without user intervention is used to transmit control signals between system 400 and display 4400, speaker 4410, or other peripheral devices 4420. Output devices may be communicatively coupled to system 400 via dedicated connections through corresponding interfaces 470, 480, and 490. Alternatively, output devices may be connected to system 400 via communication interface 450 using communication channel 460. Display 4400 and speaker 4410 may be integrated into a single unit with other components of system 400 in electronic devices such as, for example, a television set. In various examples, display interface 470 includes display drivers, such as, for example, a timing controller (TCon) chip.

[0104] Alternatively, for example, if the RF section of input 4430 is part of a separate set-top box, the display 4400 and speaker 4410 may be separate from one or more other components. In various examples where the display 4400 and speaker 4410 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.

[0105] These examples can be implemented 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 can be implemented by one or more integrated circuits. As a non-limiting example, memory 420 can be of any type suitable for the technical environment and can be implemented using any suitable data storage technology, such as optical memory devices, magnetic memory devices, semiconductor-based memory devices, fixed memory, and removable memory. As a non-limiting example, processor 410 can be of any type suitable for the technical environment and can include one or more of microprocessors, general-purpose computers, special-purpose computers, and processors based on multi-core architectures.

[0106] Various specific implementations participate in decoding. As used in this application, "decoding" may encompass all or part of a process performed, for example, on a received encoded sequence to produce a final output suitable for display. In various examples, such a process includes one or more processes typically performed by a decoder, such as entropy decoding, inverse quantization, inverse transform, and differential decoding. In various examples, such a process also includes, or alternatively includes, a process performed by a decoder of various embodiments described in this application, such as determining the size of the CU and a reference sample of the CU; determining whether to apply an interpolation filter to the reference sample of the CU based on the size of the CU; predicting the CU based on the determination of whether to apply an interpolation filter to the reference sample of the CU; determining the interpolation filter length of the interpolation filter associated with the CU based on the size of the CU; determining an interpolation reference sample based on the determined interpolation filter length and the reference sample of the CU; and predicting the CU based on the interpolation reference sample.

[0107] As another example, in one example, "decoding" refers only to entropy decoding; in another example, "decoding" refers only to differential decoding; and in yet another example, "decoding" refers to a combination of entropy decoding and differential decoding. Whether the phrase "decoding process" specifically refers to a subset of operations or broadly refers to a wider decoding process will be clear based on the specific context of the description and is believed to be well understood by those skilled in the art.

[0108] Various specific implementations participate in encoding. In a manner similar to the discussion above regarding “decoding,” the term “encoding,” as used herein, can encompass, 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 processes typically performed by an encoder, such as partitioning, differential coding, transform, quantization, and entropy coding. In various examples, such processes also include, or alternatively include, processes performed by an encoder of various embodiments described herein, such as: determining the size of the CU and a reference sample of the CU; determining whether to apply an interpolation filter to the reference sample of the CU based on the size of the CU; predicting the CU based on the determination of whether to apply the interpolation filter to the reference sample of the CU; determining the interpolation filter length of the interpolation filter associated with the CU based on the size of the CU; determining an interpolation reference sample based on the determined interpolation filter length and the reference sample of the CU; and / or predicting the CU based on the interpolation reference sample.

[0109] As another example, in one example, "decoding" refers only to entropy decoding; in another example, "decoding" refers only to differential decoding; and in yet another example, "decoding" refers to a combination of differential decoding and entropy decoding. Whether the phrase "encoding process" specifically refers to a subset of operations or broadly refers to a wider encoding process will be clear based on the specific context of the description and is believed to be well understood by those skilled in the art.

[0110] Note that the syntax elements used in this article (such as isIntraTop, isIntraLeft, cu_sbt_flag, etc.) are descriptive terms. Therefore, they do not preclude the use of other syntax element names.

[0111] When the accompanying drawings are presented as flowcharts, it should be understood that block diagrams of the corresponding devices are also provided. Similarly, when the accompanying drawings are presented as block diagrams, it should be understood that flowcharts of the corresponding methods / processes are also provided.

[0112] Various examples involve rate-distortion optimization. Specifically, during the encoding process, a balance or trade-off between rate and distortion is typically considered, often taking into account computational complexity constraints. Rate-distortion optimization is generally formulated as minimizing a rate-distortion function, which is a weighted sum of rate and distortion. Different approaches exist to solve the rate-distortion optimization problem. For example, these approaches may be based on extensive testing of all encoding options (including all considered modes or values ​​of encoding parameters) and a complete evaluation of their encoding costs and the associated distortion of the reconstructed signal after encoding and decoding. Faster methods can also be used to reduce encoding complexity, particularly for the computation of approximate distortion based on prediction or prediction of the residual signal rather than the reconstructed residual signal. A hybrid of these two approaches can also be used, such as by using approximate distortion for only some of the possible encoding options and full distortion for others. Other methods evaluate only a subset of the possible encoding options. More generally, many methods employ any of a variety of techniques to perform optimization, but optimization is not necessarily a complete evaluation of both encoding costs and associated distortion.

[0113] The specific embodiments and aspects described herein may be implemented, for example, in methods or processes, apparatus, software programs, data streams, or signals. Even if discussed only in the context of a single form of specific embodiment (e.g., discussed only as a method), specific embodiments of the discussed features may be implemented in other forms (e.g., apparatus or program). Apparatus may be implemented, for example, in suitable hardware, software, and firmware. Methods may be implemented, for example, in a processor, which generally refers to a processing device.

[0114] The processing device includes, for example, a computer, a microprocessor, an integrated circuit, or a programmable logic device. The processor also includes communication devices, such as computers, mobile phones, portable / personal digital assistants (“PDAs”), and other devices that facilitate information communication between end users.

[0115] References to “an example” or “an example” or “an embodiment” or “an embodiment” and their other variations mean that a particular feature, structure, characteristic, etc., described in connection with that example is included in at least one example. Therefore, the phrases “in an example” or “in the example” or “in an embodiment” or “in the embodiment” and any other variations appearing in various places throughout this application do not necessarily refer to the same example.

[0116] Additionally, this application may involve "determining" various types of information. Determining information may include, for example, one or more of the following: estimation information, calculation information, prediction information, or information retrieved from memory.

[0117] Furthermore, this application may relate to "accessing" various types of information. Accessing information may include, for example, receiving information, retrieving information (e.g., from memory), storing information, moving information, copying information, calculating information, determining information, predicting information, or estimating information, or more of these.

[0118] Furthermore, this application may relate to "receiving" various types of information. Like "access," "receiving" is intended to be a broad term. Receiving information may include, for example, accessing information or retrieving information (e.g., from memory) or more. Moreover, "receiving" typically involves one or more of the following during operations such as, for example, storing information, processing information, transmitting information, moving information, copying information, erasing information, calculating information, determining information, predicting information, or estimating information.

[0119] It should be understood that, for example, in the cases 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” is intended to cover selecting only the first listed option (A), or only the second listed option (B), or selecting both options (A and B). As a further example, in the cases of “A, B, and / or C” and “at least one of A, B, and C,” such phrases are intended to cover 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 and second listed options (A and B), or only the first and third listed options (A and C), or only the second and third listed options (B and C), or selecting all three options (A, B, and C). As will be apparent to those skilled in the art and related fields, this can be extended to as many items as possible listed.

[0120] Moreover, as used herein, the term "signaling" refers to (among other things) instructing the corresponding decoder to do something. For example, in some examples, encoder signals may include, for instance, parameters for determining the CU size and / or the interpolation filter of the CU, instructions for enabling CIIP, instructions for enabling TPM, instructions for enabling MMVD, etc. Thus, in these examples, the same parameters are used on both the encoder and decoder sides. Therefore, for example, the encoder may transmit (explicit signaling) specific parameters to the decoder so that the decoder can use the same specific parameters. Conversely, if the decoder already has specific parameters and others, signaling may be used without transmission (implicit signaling) to simply allow the decoder to know and select specific parameters. Bit savings are achieved in various examples by avoiding the transmission of any actual functions. It should be understood that signaling can be implemented in various ways. For example, in various examples, one or more syntax elements, tags, etc., are used to signal information to the corresponding decoder. Although the verb form of the term "signal" was mentioned above, the term "signal" may also be used as a noun in this document.

[0121] It will be apparent to those skilled in the art that the embodiments can produce various signals formatted to carry, for example, storable or transmissible information. The information may include, for example, instructions for performing a method or data generated by one of the embodiments. For example, the signal may be formatted to carry a bit stream of the example. Such signals may be formatted as, for example, electromagnetic waves (e.g., using the radio frequency portion of the spectrum) or baseband signals. Formatting may include, for example, encoding the data stream and modulating the carrier with the encoded data stream. The information carried by the signal may be, for example, analog or digital information. It is known that signals can be transmitted via various wired or wireless links. The signal may be stored on a processor-readable medium.

[0122] Each feature disclosed anywhere in this document is described, and such feature may be implemented separately / individually and in any combination with any other feature disclosed herein and / or with any feature disclosed elsewhere, whether implicitly or explicitly mentioned herein or otherwise falling within the scope of the subject matter disclosed herein.

[0123] Video coding can be performed using various structures, formats, signaling mechanisms, modes, and / or partitions (e.g., flexible multi-type tree block partitions, such as quadtree, binary tree, and / or ternary tree partitions). Intra-frame prediction can be performed. For example, one or more (e.g., 65) angular intra-frame prediction directions, including wide-angle prediction, chroma component linear model (CCLM), and / or matrix-based intra-frame prediction (MP), can be used to encode or decode video content. Inter-frame prediction can be performed. For example, affine motion models, sub-block temporal motion vector prediction (SbTMVP), adaptive motion vector precision, decoder-side motion vector correction (DMVR), triangular partitioning, combined intra-frame and inter-frame prediction (CIIP), merge mode with motion vector difference (MMVD), bidirectional optical flow (BDOF), pixel-corrected optical flow (PROF), and / or dual prediction weighted average (BPWA) can be used to encode or decode video content. Transform, quantization, and / or coefficient coding can be performed. For example, multiple primary transform options, including Discrete Cosine Transform 2 (DCT2), Discrete Sine Transform 7 (DST7), and DCT8, second-order transform coding with Low Frequency Inseparable Transform (LFNST), dependent quantization with a maximum QP increasing from 51 to 63, and / or modified transform coefficient coding, can be used to encode or decode video content. Loop filters (e.g., Generalized Adaptive Loop Filter (GALF)) can be used to encode or decode video content. Screen content coding (e.g., Intra-Block Copy (IBC) and / or Palette Mode (PLT) for 4:4:4 content) can be performed. 360-degree video coding (e.g., with or without horizontal surround motion compensation) can be performed.

[0124] Two-way motion-compensated prediction (MCP) can increase prediction efficiency, for example, by removing temporal redundancy by utilizing the temporal correlation between images. Two single prediction signals can be combined using weight values ​​(e.g., using a weight value equal to 0.5) to form a dual prediction signal. In some cases (e.g., when illumination changes rapidly from one reference image to another), prediction techniques can be designed to compensate for changes in illumination over time, for example, by applying global and / or local weights and / or offset values ​​to one or more sample values ​​in the reference images (e.g., each sample value).

[0125] (For example, each) inter-frame predicted CU may include one or more motion parameters. One or more motion parameters may include one or more of the following: motion vectors, reference picture indices and / or a list of reference pictures using the index, and / or additional information generated from samples used for inter-frame prediction. One or more motion parameters may be signaled explicitly or implicitly. When a CU is encoded with a skip mode, the CU may be associated with a PU and / or may not be associated with significant residual coefficients, encoded motion vectors Δ, or reference picture indices. In several examples (e.g., when a merge mode is specified), one or more motion parameters of a CU (e.g., the current CU) may be obtained from one or more candidates (e.g., neighboring CUs), including spatial candidates, temporal candidates, and / or other types of candidates that may be suitable for the CU (e.g., the current CU). In one or more examples, "neighboring" may be used interchangeably with "adjacent," which includes different types of neighbors, such as neighboring blocks, neighboring sub-blocks, neighboring pixels, and / or pixels adjacent to a boundary. Spatial neighbors may be adjacent in the same frame, while temporal neighbors may be located at the same position in adjacent frames. The motion vector (MV) of a CU (e.g., the current CU) can be selected from multiple motion vector (MV) candidates. The selected MV of the CU (e.g., the current CU) can be associated with a reference picture of the CU (e.g., including one or more reference samples in the reference picture). The MV associated with the reference sample can be determined based on the MV of the CU. The reference sample can be determined based on the MV associated with the reference sample. The merging mode can be applied to one or more CUs predicted by inter-frames (e.g., applied to any CU including those CUs encoded with skip mode). Explicit transmission of motion parameters can be performed (e.g., as an alternative form of the merging mode). Explicit transmission of motion parameters may include motion vectors, corresponding reference picture indices for (e.g., each) a list of reference pictures, reference picture list usage tags, and / or other information to be used (e.g., desired) for encoding and / or decoding video content. In several examples, transmission can be performed explicitly and / or for each CU.

[0126] The merged candidate list can be constructed, for example, by including one or more candidates of the following types (e.g., in order): spatial motion vector predictors (MVPs) associated with one or more spatially adjacent CUs, temporal MVPs associated with one or more juxtaposed CUs, historical MVPs from a FIFO table, pairwise average MVPs, or zero MVs.

[0127] The size of the merge list can be signaled, for example, in the slice header. In several examples, a maximum allowed size for the merge list can be specified (e.g., equal to 6). For each CU encoded in merge mode, the index specifying the best merge candidate can be encoded, for example, using truncated univariate binarization (TU). Multiple bins of merge indices can exist, where one or more bins (e.g., the first bin) can be encoded using context, and one or more bins (e.g., other than the first bin) can be encoded using bypass encoding.

[0128] Combined inter-frame and intra-frame prediction (CIIP) modes can be used to encode and / or decode CUs. For example, a signal can be sent within the video bitstream indicating whether a CIIP mode is applied to the CU. For instance, when encoding a CU using a merged mode, if the number of luminance samples in the CU (e.g., determined by the CU width multiplied by the CU height) is equal to or greater than a threshold (e.g., 64 luminance samples), and if both the CU width and CU height are less than 128 luminance samples, a signal can be sent indicating whether a CIIP mode is applied to the CU (e.g., the current CU). CIIP prediction modes can combine inter-frame prediction signals with intra-frame prediction signals. Figure 12 An exemplary CIIP mode using planar intra-frame prediction mode and inter-frame prediction mode (e.g., nearest integer MV) is shown. The inter-frame prediction signal P in CIIP mode... inter It can be derived through a similar (e.g., the same) inter-frame prediction process applied in merged mode. The intra-frame prediction signal P in CIIP mode... intra It can follow the planar pattern (e.g., Figure 12 The intra-prediction process, similar to (e.g., the same) applied in the planar mode shown, can be derived. Weighted averaging can be used, for example, to combine the intra-prediction and inter-prediction signals. The weights applied during combination can be calculated based on the coding patterns of one or more neighboring blocks of the CU (e.g., the current CU), such as the top and left neighboring blocks of the CU (e.g., the current CU).

[0129] Figure 5An example of deriving CIIP weights using top and left neighbor blocks is shown. If the top neighbor block is available and intra-coded, a flag or variable (e.g., named "isIntraTop") can be set to 1. Otherwise (e.g., if no top neighbor block is available or intra-coded), the flag or variable (e.g., "isIntraTop") can be set to 0. If the left neighbor is available and intra-coded, a flag or variable (e.g., named "isIntraLeft") can be set to 1. Otherwise (e.g., if no left neighbor block is available or intra-coded), the flag or variable (e.g., "isIntraLeft") can be set to 0. In several examples, if the sum of the two variables or flags (isIntraTop + isIntraLeft) equals 2 (e.g., if both the top and left neighbors are available and intra-coded), the CIIP weight can be set to 3. If the sum of the two variables or tags (isIntraTop + isIntraLeft) equals 1 (e.g., if only one of the top or left neighbors is available and intra-coded), the CIIP weight can be set to 2. If the sum of the two variables or tags (isIntraTop + isIntraLeft) equals 0 (e.g., if neither the top nor left neighbor is available and no intra-coded), the CIIP weight can be set to 1.

[0130] CIIP prediction can be performed as shown in Equation 1.

[0131] P CIIP =((4-wt)*P inter +wt*P intra +2)>>2 (1)

[0132] Where wt represents the CIIP weight described in this paper, P inter Represents the inter-frame prediction signal and P intra This represents the intra-frame prediction signal.

[0133] It can support Triangle Partitioning (TPM) mode for at least inter-frame prediction. Figure 6 An example of inter-frame prediction based on triangular partitioning is shown. TPM can be applied based on the size of the CU. For example, TPM can be applied (e.g., only to CUs of 8×8 or larger). Flags or variables (e.g., CU-level flags or variables) can be used to signal TPM as a type of merge mode (e.g., other types of merge modes may include regular merge mode, MMVD mode, CIIP mode, and sub-block merge mode, etc.).

[0134] When using TPM, the CU can be evenly divided into, for example, two triangular partitions (e.g., using diagonal or anti-diagonal partitioning, such as...). Figure 6 (As shown). Each triangular partition in the CU can use its own motion for inter-frame prediction. Single prediction (e.g., single prediction only) may be allowed for each partition. Each partition may include a motion vector and a reference index. For example, single-prediction motion constraints (e.g., similar to regular dual prediction) may be applied to ensure that two (e.g., only two) motion-compensated predictions are performed on the CU. The single-prediction motion of each partition can be derived as described herein.

[0135] If the TPM is used for the CU (e.g., the current CU), a flag or variable indicating the orientation (e.g., diagonal or anti-diagonal) of the triangular partition can be signaled. If the TPM is used for the CU (e.g., the current CU), two merge indices (e.g., one merge index per partition) can be signaled. The maximum TPM candidate size can be signaled (e.g., explicitly and / or at the slice level). The maximum TPM candidate size can specify the syntax binarization of the TPM merge indices. After predicting the triangular partitions (e.g., each triangular partition within a triangular partition), a blending process with adaptive weights can be used, for example, to adjust one or more sample values ​​along the diagonal and / or anti-diagonal edges. For example, as in other prediction modes, the prediction signal for the CU (e.g., for the entire CU) can be used for the transformation and quantization of the CU. The motion field of the CU predicted using the TPM can be stored in a 4×4 cell as described herein.

[0136] In several examples, TPM may not be used in conjunction with Subblock Transformation (SBT). For example, when a TPM flag or variable has a value of 1 (e.g., indicating that TPM has been applied), an SBT flag or variable (e.g., cu_sbt_flag) may be determined to be 0 (e.g., there is no explicit signaling with an SBT flag or variable).

[0137] Figure 7 An example of single-predictive motion vector selection for TPM is shown. The single-predictive candidate list can be derived based on (e.g., directly from) a merged candidate list constructed as described herein. For example, using n to denote the index of a single-predictive motion in the triangular single-predictive candidate list, the LX motion vector of the nth expanded merged candidate (where X equals the parity of n) can be used as the nth single-predictive motion vector for TPM. These motion vectors in... Figure 7 The symbol is marked as "x". In several examples (e.g., when there is no corresponding LX motion vector for the nth extended merge candidate), the same candidate's L(1-X) motion vector (e.g., instead of the LX motion vector) can be used as a single predicted motion vector for TPM.

[0138] You can apply blending along the edges of the triangular partition. Figure 8Exemplary weights that can be used for blending are shown. For example, blending can be applied to two prediction signals (e.g., after predicting triangular partitions P1 and P2 using their own motion) to, for example, derive samples around diagonal and / or anti-diagonal edges. As an example, the following weights can be used for blending: {7 / 8, 6 / 8, 5 / 8, 4 / 8, 3 / 8, 2 / 8, 1 / 8} for luminance and {6 / 8, 4 / 8, 2 / 8} for chrominance, such as... Figure 8 As shown.

[0139] For example, motion vectors of a CU encoded in Triangle Partitioning Pattern (TPM) can be stored in 4×4 cells. These motion vectors may include single-predicted motion vectors and / or double-predicted motion vectors, and can be stored based on the corresponding positions of the relevant 4×4 cells. For example, Mv1 and Mv2 can represent the single-predicted motion vectors of partition 1 (P1) and partition 2 (P2), respectively, if the 4×4 cells are located in unweighted regions (e.g., Figure 8 If the unweighted region is selected, then Mv1 or Mv2 can be stored in the 4×4 cell. Figure 8 The unweighted regions may include P1 and / or P2. If the 4×4 cells are located in the weighted region (e.g., Figure 8 If a weighted region is defined, then a dual-predictive motion vector can be stored for that 4×4 cell. The dual-predictive motion vector can be obtained, for example, using a blending process with adaptive weights as described herein. The dual-predictive motion vector can be obtained (e.g., derived) from Mv1 and / or Mv2 based on one or more of the following: If Mv1 and Mv2 come from different lists of reference images (e.g., one from reference image list L0 and the other from reference image list L1), then Mv1 and Mv2 can be combined to form a dual-predictive motion vector. If both Mv1 and Mv2 come from a first list of reference images (e.g., L0), but a reference image for Mv2 or Mv1 appears in a second list of reference images (e.g., L1), then the motion vectors with reference images in the second list of reference images can be converted to motion vectors associated with the second list of reference images using the reference images in the second list of reference images, and the two motion vectors (e.g., after the conversion) can be combined to form a dual-predictive motion vector. If both Mv1 and Mv2 come from the first reference image list (e.g., L0), and neither the reference image for Mv2 nor Mv1 appears in the second reference image list (e.g., L1), then a single predicted motion (e.g., only Mv1) can be stored.

[0140] Merging patterns with motion vector differences (MMVD) can be used, for example, for CUs. In merging patterns, implicitly derived motion information can be used (e.g., directly) to generate predicted samples for CUs (e.g., the current CU). For example, after sending jump and merge tags, MMVD tags can be signaled. MMVD tags can indicate whether the MMVD pattern is used for the CU.

[0141] In MMVD, merge candidates can be selected. Merge candidates can be modified (e.g., corrected) via signaled MVD information. MVD information may include one or more of the following: merge candidate indications (e.g., merge candidate flags), indices indicating (e.g., specifying) the magnitude of motion, and / or indices indicating the direction of motion. In MMVD, merge candidates (e.g., the first two candidates in the merge list) can be selected to serve as the MV basis. The merge candidate indication specifies which candidate in the merge list is used as the merge candidate.

[0142] The resolution / precision of the motion vector (MV) can be 1 / 16 of the brightness sample. For motion-compensated prediction (MCP), a reference sample at the fractional location (e.g., the sample value or the MV associated with the reference sample) can be determined via interpolation (e.g., such as...). Figure 11(As shown in 1104). Interpolation can be based on one or more reference samples, for example, at one or more integer positions. The MV associated with the reference sample (e.g., at an integer position) can be determined based on the MV associated with the CU. The video processing apparatus can support multiple (e.g., four) types of interpolation filters, including, for example, 8-tap filters, 6-tap filters, 4-tap filters, and / or 2-tap filters. The number of taps of the filter can correspond to or indicate the length of the filter (e.g., more taps can correspond to a larger length). In the example, the interpolation filter length can be selected for the interpolation filter associated with the CU, and the interpolation reference sample can be determined based on the determined interpolation filter length, for example, by interpolating one or more reference samples of the CU. The CU can be predicted based on the interpolation reference sample, for example, by obtaining an MV with fractional pixel resolution or accuracy. An MV with fractional pixel resolution or accuracy can provide higher prediction accuracy compared to an MV with integer pixel resolution or accuracy. In some examples, the fractional part of the MV may lead to increased computational complexity (e.g., due to multiplications involved in interpolation) and / or higher demands on memory access bandwidth (e.g., to access multiple reference samples during interpolation). The cost associated with the fractional part of the MV (e.g., due to computation and memory access) can increase with increasing interpolation filter length. Under certain conditions, using shorter interpolation filter lengths (e.g., 4-tap or 2-tap instead of 8-tap or 6-tap) and / or not using interpolation filtering (e.g., using a 1-tap interpolation filter length) can reduce processing costs while still maintaining prediction accuracy. When the interpolation filter length is 1, for example, if a 1-tap interpolation filter is applied to a reference sample, the interpolated reference sample can be the same as the reference sample.

[0143] For the CIIP mode described in this paper, intra-frame prediction signals and inter-frame prediction signals can be combined based on a weighted average. Shorter interpolation filters or nearest-nearest-integer techniques (e.g., such as...) Figure 12 (As shown) can be adaptively used, for example, by a video processing device for use in CIIP mode for inter-frame prediction signals. For example, the accuracy loss of the inter-frame prediction signal (if any) can be compensated by the intra-frame prediction signal according to the associated weighting factor.

[0144] For the TPM mode described herein, mixing of samples applied around diagonal and / or anti-diagonal edges can be performed based on a weighted average. The video processing apparatus can be configured to adaptively use shorter interpolation filters or nearest integer techniques in the TPM mode, at least for samples located in the mixing region. Accuracy loss of the inter-frame prediction signal in one TPM partition (if any) can be compensated, for example, based on a weighted average of the inter-frame prediction signal at another TPM partition.

[0145] For a reference sample determined to have a smoothing intensity value (e.g., the surface of an object associated with the reference sample is smooth, or the reference sample is reconstructed by a smoothing operation such as Gaussian filtering), the video processing apparatus can be configured to use a shorter interpolation filter or apply the nearest integer technique for inter-frame prediction associated with the reference sample.

[0146] Video processing apparatuses can be configured to adaptively apply interpolation filtering (e.g., using adaptive interpolation filters) for motion compensation prediction (MCP). Adaptive interpolation filtering can reduce interpolation-induced computational complexity and / or memory access bandwidth usage without significantly sacrificing coding performance. The video processing apparatus can adaptively apply interpolation filtering based on one or more factors, including, for example, coding mode, video content, CU size, etc. For example, the video processing apparatus can be configured to use shorter interpolation filters or not perform interpolation filtering (e.g., applying the nearest integer technique or a 1-tap interpolation filter) based on the coding mode, video content, and / or CU size to achieve a trade-off between coding efficiency, computational complexity, and memory access bandwidth. In an example, the video processing apparatus can determine whether to apply an interpolation filter to a reference sample of the CU based on the CU size. If the interpolation filter length is 1, the interpolation filter may not be applied to the reference sample. The video processing apparatus can adaptively determine and / or adjust the precision of motion vectors, for example, to reduce signaling overhead (e.g., on the encoder side) and / or achieve higher coding efficiency. If the video processing device determines that an interpolation filter should be applied, it may apply the interpolation filter to a reference sample of the CU, for example, to generate an interpolated reference sample, and use the interpolated reference sample to predict the CU. If the video processing device determines that an interpolation filter should not be applied, it may not apply the interpolation filter to the reference sample of the CU and use the reference sample (e.g., without interpolation) to predict the CU.

[0147] Temporal scaling can be skipped (e.g., removed) in MMVD. For example, if the CU is encoded using true double prediction mode, temporal scaling can be removed in MMVD. Removing temporal scaling in MMVD can reduce encoding complexity and / or improve encoding efficiency.

[0148] The video processing apparatus described herein can be configured to adaptively select interpolation filters based on the coding mode. For example, in CIIP mode, the video processing apparatus can determine, for example, a weighted combination of intra-frame prediction signals and inter-frame prediction signals at each sample location, as defined in Equation 1. The contribution of the inter-frame prediction signal to the final prediction value can vary, for example, according to the weight value wt (e.g., as defined in Equation 1) used during the combination of the intra-frame and inter-frame prediction signals. When applying an inter-frame prediction signal with a lower weight value such as (4–wt) based on Equation 1, the video processing apparatus can select a shorter interpolation filter. The video processing apparatus can apply the nearest integer technique. The nearest integer technique can be considered as a 1-tap interpolation filter or the shortest interpolation filter. A 1-tap interpolation filter can be the shortest interpolation filter and / or can represent no interpolation filtering. In some examples, the interpolation filter length of the CU can be determined to be 1 tap and can be equivalent to skipping the interpolation filter (filter) for one or more reference samples of the CU.

[0149] For example, in several examples, the video processing apparatus may map interpolation filter lengths to corresponding weight values ​​(e.g., wt) based on a mapping table. Table 1 shows an exemplary mapping table between weight values ​​wt and interpolation filter lengths. As shown in Table 1, exemplary adaptive MV precision (e.g., corresponding to the corresponding filter length) can be determined for different weight values ​​(e.g., in CIIP mode).

[0150] Table 1: Exemplary Adaptive MV Precision with Different Weight Values ​​in CIIP Mode

[0151] 1 8 taps 2 6 taps, 4 taps, or 2 taps 3 Most recent integer (e.g., 1 tap)

[0152] In several examples, the video processing apparatus may be configured to use a recent integer method, for example, independent of the weight values, to determine the inter-frame prediction components of the CIIP mode (e.g., the recent integer method may be used for various weight values ​​including 1, 2, and 3).

[0153] The video processing apparatus can be configured to apply adaptive interpolation filtering in TPM mode. As described herein, the video processing apparatus can be configured to perform a weighted average-based mixing of sub-block samples located at diagonal and / or anti-diagonal edges (e.g., on or adjacent to diagonal and / or anti-diagonal edges) during TPM mode. The video processing apparatus can be further configured to determine non-edge sample values ​​(e.g., for samples not located on or adjacent to diagonal and / or anti-diagonal edges) using a first interpolation filter (e.g., an 8-tap interpolation filter) and edge sample values ​​using a second interpolation filter (e.g., a shorter filter, such as a 6-tap, 4-tap, 2-tap filter, or a 1-tap filter with no interpolation or any interpolation) using a second interpolation filter (e.g., a shorter filter, such as a 6-tap, 4-tap, 2-tap filter, or a 1-tap filter with no interpolation or any interpolation). In several examples, the video processing apparatus can be configured to determine edge sample values ​​using a nearest integer technique (e.g., no interpolation filter). The video processing apparatus can compensate for any loss of prediction accuracy by using a shorter interpolation filter with weighted mixing (e.g., performed after interpolation filtering).

[0154] Figure 9 Examples of using different interpolation filters for sub-blocks inside or outside the TPM edge region are shown. As illustrated, the video processing apparatus can use short interpolation filters (e.g., 6-tap, 4-tap, 2-tap, or 1-tap interpolation filter lengths) for samples of sub-blocks located at diagonal or anti-diagonal edges (e.g., on or adjacent to diagonal or anti-diagonal edges). The video processing apparatus can use short interpolation filters independently of the weights associated with the samples, pairing samples within the sub-block (e.g., an 8×8 sub-block) (e.g., all samples). For example, as... Figure 9 As shown, the video processing device can process the first weight pair (e.g., such as...). Figure 8 The edge samples associated with 7 / 8 and 1 / 8 as shown, and the second weight pair (e.g., as shown) Figure 8 The edge samples associated with 4 / 8 and 4 / 8 shown are filtered using short interpolation filters. Figure 9 In this context, each (for example) square can represent an 8×8 sub-block, while Figure 8 Each (e.g.) square in the diagram can represent a sample.

[0155] In several examples, the video processing device can be configured to process samples located in a weighted region (e.g., samples associated with weights, such as...). Figure 8 (As shown) a second (e.g., shorter than the first) interpolation filter is used, and samples located in unweighted regions (e.g., samples not associated with weights, such as...) are also used. Figure 8 (As shown) a first (e.g., conventional or original) interpolation filter (e.g., an 8-tap filter) is used.

[0156] In several examples, the video processing apparatus may be configured to use different interpolation filters (e.g., filters with shorter lengths) for sub-block samples located at diagonal edges (e.g., on or adjacent to diagonal edges) and samples located at anti-diagonal edges (e.g., on or adjacent to anti-diagonal edges). For example, the video processing apparatus may be configured to consider the sample (e.g., as shown in the example) when determining that the interpolation filter length is suitable for the sample. Figure 8 (As shown) the associated weights.

[0157] Figure 10 An example of an adaptive interpolation filter for samples associated with different weights is shown (e.g., in TPM mode). For example, as Figure 10 As shown, the video processing apparatus can be configured to handle a first weight pair (e.g., 7 / 8, 1 / 8) (see, for example, see...). Figure 8 The edge samples associated with the second weight pair (e.g., 4 / 8, 4 / 8) are interpolated using a 6-tap interpolation filter, and the edge samples associated with the second weight pair (e.g., 4 / 8, 4 / 8) are interpolated using a 1-tap interpolation filter (e.g., the nearest integer technique). The number of taps in the interpolation filter indicates the length of the interpolation filter.

[0158] Video processing apparatuses can be configured to adaptively apply interpolation filtering in other weighted double prediction modes, such as double prediction with CU-level weights. For example, the video processing apparatus can adaptively (e.g., dynamically) determine the length of the interpolation filter based on one or more weight values ​​to be applied to the double prediction. The video processing apparatus can also determine the length of the interpolation filter based on predefined values ​​(e.g., independent of the applicable weight values). Potential losses (if any) associated with using shorter-length interpolation filters in these double prediction modes can be compensated for by the weighting applied during double prediction.

[0159] For example, adaptive interpolation filtering can be used in dual prediction mode. Shorter-length interpolation filters (e.g., the nearest integer method) can be used for inter-frame prediction signals, which reduces the computational complexity of MC (Multi-Card Memory). Shorter-length interpolation filters can be shorter than those used in one or more other modes such as CIIP mode, TPM mode, and / or weighted dual prediction mode. The use of shorter-length interpolation filters may not result in significant coding performance loss. Combined signals in dual prediction (e.g., weighted or equivalent combinations) can compensate for coding losses from single prediction signals.

[0160] Inter-frame prediction in CIIP can use dual prediction (e.g., dual prediction mode). In several examples, if the inter-frame prediction portion of CIIP uses dual prediction mode, a shorter interpolation filter (e.g., the nearest integer method) can be used to generate the inter-frame prediction signal. A shorter interpolation filter can be used regardless of the weights used to combine the intra-frame and inter-frame prediction signals. In several examples, if the inter-frame prediction portion of CIIP uses dual prediction mode, the weights used to combine the intra-frame and inter-frame prediction signals can be considered to determine the length of the interpolation filter. For example, when the weight value wt is 2 or 3, and the inter-frame prediction signal is generated via dual prediction, a shorter interpolation filter (e.g., the nearest integer method) can be used to generate one or more inter-frame prediction signals. When the weight value wt is 2 or 3, the intra-frame prediction signals can be equally or more important during the weighted combination operation in CIIP.

[0161] Video processing apparatuses can be configured to apply adaptive interpolation filtering based on (e.g., the video content to be processed or being processed). For example, the video processing apparatus can adaptively select an interpolation filter based on whether the video content includes sharp edges and / or whether the video content includes smoothed sample values ​​(e.g., naturally smoothed values ​​(such as those associated with the surface of a smooth object) or reconstructed smoothed sample values ​​(such as interpolated reference samples with high MV accuracy)).

[0162] The video processing device may send (e.g., if the video processing device is an encoder) or receive (e.g., if the video processing device is a decoder) signaling indicating whether a reference sample in a reference CU or reference block has smooth sample values ​​or sample values ​​associated with sharp transitions such as edges. For example, when reconstructing reference blocks in the same or different images, the indication may be sent during motion estimation (e.g., from the encoder side) and / or the indication may be set or marked during motion compensation (e.g., on the decoder side).

[0163] For example, when evaluating different encoding modes, a video processing device (e.g., an encoder) can analyze the characteristics of the video content. The smoothness detection techniques described herein can be used for this analysis. If smooth content (e.g., smoothed sample values) is identified in the CU based on the analysis, the video processing device can send an indication that the CU contains smooth content. In response to receiving such an indication, the video processing device (e.g., a decoder) can apply a shorter interpolation filter to one or more samples of the CU. An indication (e.g., of smoothness) can be provided for intra-frame predicted CUs (e.g., for intra-frame CUs only). Smoothness information of a reference region can be determined (e.g., inferred) from smoothness information of a reference image associated with motion vectors (e.g., MVs involved in motion estimation or motion compensation).

[0164] Video coding apparatuses can be configured to determine (e.g., detect) the smoothness of video content based on gradients in the horizontal, vertical, and / or one or two diagonal directions. These gradients can be obtained (e.g., computed) using an array such as a 1-D Laplacian. For example, a video coding apparatus can determine a gradient threshold based on a computed gradient map of a CU by statistically measuring whether the CU is smooth, and / or by calculating the standard deviation of luminance samples within the CU (e.g., the calculated standard deviation of luminance samples within the CU can statistically indicate whether the CU is smooth).

[0165] When a reference CU or block associated with a CU (e.g., the current CU) has been decoded or reconstructed, a video decoding apparatus (e.g., a decoder) can determine the smoothness of the reference CU or block and / or adaptively select a long interpolation filter or a short interpolation filter based on that determination. Smoothness analysis can be performed on intra-frame CUs (e.g., only intra-frame CUs). Smoothness information (e.g., which or which CUs and / or blocks are smooth) can be stored for processing subsequent video (e.g., pictures, frames, slices, etc.). For inter-frame CUs, the video decoding apparatus can determine (e.g., infer) the smoothness information of a reference region from stored smoothness information of a reference picture and its associated motion vectors. For example, the video decoding apparatus can use the techniques described herein to reconstruct one or more reference CUs and / or blocks and / or perform smoothness detection based on one or more reconstructed CUs or blocks.

[0166] For example, when the video content includes or is determined to include sharp edges (e.g., screen content), the video processing apparatus may be configured to apply the most recent integer during motion compensation. For example, in some examples, when the video content includes smoothed sample values ​​(e.g., as determined by the video processing apparatus), the video processing apparatus may be configured to use a shorter interpolation filter or the most recent integer during motion compensation.

[0167] The video processing apparatus can be configured to adaptively select interpolation filters based on the size of the CU (e.g., such as...). Figure 11 (As shown in 1102). The CU size can represent the spatial resolution of a sub-picture (e.g., the CU can be considered as a sub-picture). The video processing apparatus can obtain the size of the CU. When the video processing apparatus (e.g., an encoder) considers a sub-picture (e.g., a CU) of a certain size to find a match from a reference picture, the MV precision to be used (e.g., should be used) to find the match can be determined based on the size of the CU. For example, the video processing apparatus can use a higher MV precision to find a match for a larger CU (e.g., due to the higher spatial resolution of the CU) and use a lower MV precision to find a match for a smaller CU.

[0168] The video processing apparatus may allow (e.g., only) 4×4 CUs for affine mode, while 8×4 or 4×8 CUs may be allowed for inter-frame coding mode (e.g., the maximum CU size allowed for inter-frame mode may be 128×128). The video processing apparatus may be configured (e.g., the video processing apparatus may be allowed to) use one or more interpolation filters from corresponding groups (e.g., having different lengths including at least a first length and a second length) for different ranges of CU sizes (e.g., at least a first CU size and a second CU size). The video processing apparatus may be configured to select an interpolation filter based on the CU size or determine the length of the interpolation filter associated with the CU (e.g., as shown in the image). Figure 11 (As shown in 1102). For example, the video processing apparatus may be configured to use a first (e.g., shorter interpolation filter) for samples of a first CU (e.g., a larger CU) and a second (e.g., longer interpolation filter) for samples of a second (e.g., smaller) CU.

[0169] An affine pattern CU may include one or more 4×4 sub-blocks. A video processing apparatus may perform motion compensation on such an affine pattern CU using the MV associated with the 4×4 sub-blocks (e.g., 4×4 sub-blocks of a CU). These 4×4 sub-block MVs may be derived from the same set (e.g., two or three) of CU affine MVs. The video processing apparatus may (e.g., independently of the 4×4 sub-block size) select an interpolation filter based on the size of the CU or determine the length of the interpolation filter associated with the CU.

[0170] When considering the CU size to determine the length of the interpolation filter, the determined length of the interpolation filter can be considered to determine the CU size constraint. For example, CIIP mode might not be applied to a smaller CU (e.g., an 8×8 CU). Not applying CIIP mode to a smaller CU reduces coding complexity. If a shorter-length interpolation filter (e.g., a 2-tap or nearest-integer method (1-tap)) is determined for the CU based on one or more other suggested factors (e.g., content-dependent, image-dependent, etc.), which reduces CIIP complexity, then the CU size constraint (e.g., constraint) can be removed. CU size constraints (e.g., large or small CUs do not apply CIIP) can be used to enable or determine whether to enable CIIP mode in the CU. For example, in some prediction modes such as dual prediction mode, the CU size constraint can be removed when a shorter-length interpolation filter (e.g., a 2-tap, 1-tap, or nearest-integer method) is determined for the CU.

[0171] In several examples, CIIP mode can be applied to small CUs (e.g., 4×8 or 8×4 CUs) when using short-length interpolation filters or the nearest integer method.

[0172] CIIP can be applied to non-small CUs (e.g., 8×8 and larger CUs). Integer MVs can be used in CIIP when using the nearest integer method.

[0173] In several examples, the small CUs (e.g., 4×8 or 8×4 CUs) of CIIP encoding may or may not use integer MVs.

[0174] In several examples, when CIIP mode is applied to a small CU (e.g., a 4×8 or 8×4 CU), CIIP signaling can be skipped. For small CUs (e.g., 4×8 or 8×4 CUs), many other coding modes (e.g., TPM mode) may not be applicable. When other coding modes are not applicable, it may not be necessary to distinguish which mode is applied via signaling. In this case, for example, because no associated signaling bits are sent, CIIP can be used to derive (e.g., directly derive) the small CU (e.g., a merged mode CU not in regular merged mode) without resolving the signaling bits.

[0175] When CIIP is applied to small CUs (e.g., 4×8 or 8×4 CUs), and if the small CU is encoded with CIIP, signaling can be skipped. For example, a CIIP-encoded small CU may not use integer MV because the complexity of the small CU is insignificant. The complexity of the small CU may be insignificant due to the use of single prediction.

[0176] Filter selection can be adjusted based on image type. For example, image-dependent adaptive interpolation filtering can be used in one or more modes. Shorter-length interpolation filters can be used (e.g., only) for low-latency images. When shorter-length interpolation filters are used for low-latency images, lower MC complexity and / or latency can be achieved. MC accuracy may be more important than MC complexity for low-latency images, for example, making it possible to use (e.g., always use) longer interpolation filter lengths for low-latency images.

[0177] For inter-frame prediction signals generated in CIIP mode, it's possible to consider whether the prediction is for dual prediction and / or the picture type. In CIIP, if dual prediction mode is used for inter-frame prediction and the picture type is a low-latency picture, a shorter interpolation filter length (e.g., the nearest integer method) can be used to generate one or more inter-frame prediction signals. In CIIP, if dual prediction mode is used for inter-frame prediction, the weight value wt used is 2 or 3, and the picture type is a low-latency picture, a shorter interpolation filter length (e.g., the nearest integer method) can be used to generate one or more inter-frame prediction signals.

[0178] The video processing apparatus can be configured to perform adaptive interpolation filtering based on various combinations of the methods described herein.

[0179] For example, a video processing apparatus can be configured to adaptively determine the accuracy of motion vectors using a hybrid approach. The accuracy of the motion vector (MV) may not significantly change the complexity of the interpolation operation. The accuracy of the MV determines the number of bits to be used to signal MV values ​​(such as MV difference). The number of bits to be used to signal MV values ​​can affect video coding performance. For example, the video processing apparatus can adaptively determine the MV accuracy based on various combinations of the methods described herein to improve coding efficiency. For example, if the CIIP mode is extended to an explicit inter-frame mode, the MV accuracy may depend on weights (e.g., applied or to be applied). The video processing apparatus may set the initial MV accuracy at a quarter-luminance sample (e.g., 1 / 4-PEL). With such a quarter-luminance sample accuracy, two bits may be needed to signal fractional motion information (e.g., MVD). If the weight value (e.g., wt as described herein) is set to 3, the sample values ​​of inter-frame prediction are negligible (e.g., as shown in Equation 1). In these examples (e.g., when the values ​​of inter-frame prediction are negligible), lower MV accuracy, such as half-luminance sample (e.g., 1 / 2-PEL) accuracy, can be signaled. Using this half-luminance sample precision, one bit might be needed to signal motion information. Therefore, bit savings can be achieved for each applicable coding unit (e.g., when using half-luminance sample precision instead of quarter-luminance sample precision).

[0180] When using MMVD, time scaling can be applied if the starting MV of the CU is a double-predicted MV from two reference images to an image (e.g., the current image) with different distances (e.g., the difference in POC).

[0181] If true double prediction mode is used to encode the CU, temporal scaling can be skipped (e.g., removed) in MMVD. In true double prediction mode, one of the two reference images can be before the image (e.g., before the current image in display order), and the other of the two reference images can be after the image (e.g., after the current image in display order). When temporal scaling is not applied in MMVD, complexity can be reduced and / or higher coding efficiency can be achieved. In true double prediction mode, one or more final predicted signals may not change significantly (e.g., may not change) regardless of whether temporal scaling is performed.

[0182] The merged motion vector difference can be derived as follows. If Sign(currPocDiffL0) equals Sign(currPocDiffL1), then the list-0 reference image L0 and the list-1 reference image L1 can come from the same side of the image (e.g., forward or backward). The image can include the current image. Otherwise, if (Sign(currPocDiffL0) does not equal Sign(currPocDiffL1)), then the two reference images can come from opposite sides of the image (e.g., one reference image comes from the forward direction of the current image, and the other reference image comes from the reverse direction of the current image). When the two reference images come from two different directions (e.g., when Sign(currPocDiffL0) does not equal Sign(currPocDiffL1)), time scaling may not be applied (e.g., skipped).

[0183] The brightness-merged motion vector differences mMvdL0 and mMvdL1 can be obtained as follows (e.g., derived):

[0184] If both predFlagL0 and predFlagL1 are equal to 1, then the following can be applied:

[0185] currPocDiffL0=DiffPicOrderCnt(currPic,RefPicList[0][refIdxL0]) (2)

[0186] currPocDiffL1=DiffPicOrderCnt(currPic,RefPicList[1][refIdxL1]) (3)

[0187] If currPocDiffL0 equals currPocDiffL1, then the following can be applied:

[0188] mMvdL0[0]=MmvdOffset[xCb][yCb][0] (4)

[0189] mMvdL0[1]=MmvdOffset[xCb][yCb][1] (5)

[0190] mMvdL1[0]=MmvdOffset[xCb][yCb][0] (6)

[0191] mMvdL1[1]=MmvdOffset[xCb][yCb][1] (7)

[0192] Otherwise, if Abs(currPocDiffL0) is greater than or equal to Abs(currPocDiffL1), then...

[0193] The following can be applied:

[0194] mMvdL0[0]=MmvdOffset[xCb][yCb][0] (8)

[0195] mMvdL0[1]=MmvdOffset[xCb][yCb][1] (9)

[0196] If RefPicList[0][refIdxL0] is not a long-term reference image, then RefPicList[1][refIdxL1]

[0197] If it is not a long-term reference image, and Sign(currPocDiffL0) equals Sign(currPocDiffL1), then the following can be applied:

[0198] td=Clip3(-128,127,currPocDiffL0) (10)

[0199] 1tb=Clip3(-128,127,currPocDiffL1) (11)

[0200] tx=(16384+(Abs(td)>>1)) / td (12)

[0201] distScaleFactor=Clip3(-4096,4095,(tb*tx+32)>>6) (13)

[0202] mMvdL1[0]=Clip3(-2 15 ,2 15 -1,(distScaleFactor*mMvdL0[0]+ (14)128-(distScaleFactor*mMvdL0[0]>=0))>>8)

[0203] mMvdL1[1]=Clip3(-2 15 ,2 15 -1,(distScaleFactor*mMvdL0[1]+ (15)128-(distScaleFactor*mMvdL0[1]>=0))>>8)

[0204] Otherwise, the following can be applied:

[0205] mMvdL1[0]=Sign(currPocDiffL0)==Sign(currPocDiffL1)? mMvdL0[0]:-mMvdL0[0] (16)

[0206] mMvdL1[1]=Sign(currPocDiffL0)==Sign(currPocDiffL1)? mMvdL0[1]:-mMvdL0[1] (17)

[0207] Otherwise (Abs(currPocDiffL0) is less than Abs(currPocDiffL1)), then the following can be applied:

[0208] mMvdL1[0]=MmvdOffset[xCb][yCb][0] (18)

[0209] mMvdL1[1]=MmvdOffset[xCb][yCb][1] (19)

[0210] If RefPicList[0][refIdxL0] is not a long-term reference image, then RefPicList[1][refIdxL1]

[0211] If it is not a long-term reference image, and Sign(currPocDiffL0) equals Sign(currPocDiffL1), then the following can be applied:

[0212] td=Clip3(-128,127,currPocDiffL1) (20)

[0213] tb=Clip3(-128,127,currPocDiffL0) (21)

[0214] tx=(16384+(Abs(td)>>1)) / td (22)

[0215] distScaleFactor=Clip3(-4096,4095,(tb*tx+32)>>6) (23)

[0216] mMvdL0[0]=Clip3(-2 15 ,2 15 -1,(distScaleFactor*mMvdL1[0]+ (24)128-(distScaleFactor*mMvdL1[0]>=0))>>8)

[0217] mMvdL0[1]=Clip3(-2 15 ,2 15 -1,,(distScaleFactor*mMvdL1[1]+ (8-405)128-(distScaleFactor*mMvdL1[1]>=0))>>8))

[0218] Otherwise, the following can be applied:

[0219] mMvdL0[0]=Sign(currPocDiffL0)==Sign(currPocDiffL1)? mMvdL1[0]:-mMvdL1[0] (25)

[0220] mMvdL0[1]=Sign(currPocDiffL0)==Sign(currPocDiffL1)? mMvdL1[1]:-mMvdL1[1] (26)

[0221] Figure 11 A method 1100 for performing adaptive interpolation based on CU size is illustrated. Method 1100 can be used, for example, to apply motion compensation to an encoding unit. Method 1100 can be implemented by a video processing apparatus including a decoder and / or encoder as described herein, and the examples disclosed herein can be adapted to... Figure 11 The method shown operates as described. Method 1100 may include 1102, 1104, and 1106. At 1102, the video processing apparatus may determine the interpolation filter length of the interpolation filter associated with the CU based on the size of the CU. At 1104, the video processing apparatus may generate an interpolation reference sample based on the determined interpolation filter length of the interpolation filter and a reference sample of the CU. At 1106, the video processing apparatus may predict the CU based on the interpolation reference sample. When Figure 11 When the method is implemented by the decoder, 1102 to 1106 can be associated with CU decoding based on interpolated reference samples. Figure 11 When the method is implemented by the encoder, 1102 to 1106 can be associated with CU encoding based on interpolated reference samples.

[0222] This document describes numerous embodiments. Features of the embodiments may be provided individually or in any combination across various claim classes and types. Furthermore, embodiments may include one or more of the features, devices, or aspects described individually or in any combination across various claim classes and types (such as, for example, any of the following).

[0223] The decoder can determine the interpolation filter length of the interpolation filter associated with the CU. For example, as described herein, the decoder (such as based on...) Figure 11An exemplary decoder 300 operating in the exemplary method shown herein can determine the interpolation filter length of the interpolation filter associated with the CU based on the size of the CU. For example, as described herein, the decoder can determine an interpolation reference sample based on the determined interpolation filter length of the interpolation filter and a reference sample based on the CU. For example, as described herein, the decoder can predict the CU based on the interpolation reference sample. In some examples as described herein, the decoder can determine the size of the CU and a reference sample of the CU; determine whether to apply an interpolation filter to the reference sample of the CU based on the size of the CU; and predict the CU based on the determination of whether to apply an interpolation filter to the reference sample of the CU. As described herein, the decoder can determine that the interpolation filter length of the interpolation filter is 1 based on the size of the CU, can determine that the interpolation filter length of the interpolation filter is 1 without applying the interpolation filter to the reference sample, and can predict the CU using the reference sample of the CU. As described herein, the decoder can determine the interpolation filter length of the interpolation filter associated with the CU based on the size of the CU. When the interpolation filter length is not 1, an interpolation reference sample can be determined based on the determined interpolation filter length and a reference sample of the CU, and the CU can be predicted based on the interpolation reference sample. For example, in the merging mode described herein, the decoder can select the MV of the CU from multiple MV candidates. For example, the decoder can use the selected MV candidate as described herein to determine the MV associated with the reference sample based on the MV of the CU. For example, as described herein, the decoder can determine the reference sample based on the MV associated with the reference sample. For example, as described herein, the decoder can perform interpolation using the reference sample (e.g., at an integer position in the reference CU) and an interpolation filter with a determined interpolation filter length to determine the interpolation reference sample (e.g., at a fractional position associated with the reference CU). For example, as described herein, for a 4×4 sub-block in a CU, the decoder can determine the MV of the 4×4 sub-block in the CU based at least on the MV associated with the CU, and predict the CU in affine mode based on the determined MV of the 4×4 sub-block in the CU. For example, as described herein, the decoder can determine the first interpolation filter length of the first interpolation filter associated with the first CU based on the first CU size, and determine the second interpolation filter length of the second interpolation filter associated with the second CU based on the second CU size. For example, as described herein, when the first CU size is greater than the second CU size, the first interpolation filter length is less than the second interpolation filter length. For example, as described herein, the decoder can determine the interpolation filter length based on the number of taps of the interpolation filter used to indicate the interpolation filter length. For example, as described herein, when the interpolation filter length is 1, the decoder can determine that the interpolated reference sample is the same as the reference sample. For example, as described herein, the decoder can determine that the interpolation filter associated with the CU is an adaptive interpolation filter.

[0224] Decoding tools and techniques, including one or more of entropy decoding, inverse quantization, inverse transform, and differential decoding, can be used to implement [the following] in the decoder. Figure 11The methods described herein. These decoding tools and techniques can be used to enable one or more of the following: determining the interpolation filter length of an interpolation filter associated with a CU; for example, determining the interpolation filter length of an interpolation filter associated with a CU based on the size of the CU, as described herein; for example, determining an interpolation reference sample based on the determined interpolation filter length of the interpolation filter and a reference sample of the CU, as described herein; for example, predicting the CU based on the interpolation reference sample, as described herein; for example, determining the size of the CU and a reference sample of the CU, as described herein; for example, determining whether to apply an interpolation filter to a reference sample of the CU based on the size of the CU, as described herein; for example, determining whether to apply an interpolation filter to a reference sample of the CU based on the size of the CU, as described herein. To predict CU; for example, as described herein, the interpolation filter length of the interpolation filter is determined to be 1 based on the size of the CU, the interpolation filter is not applied to the reference sample based on the determined interpolation filter length of the interpolation filter being 1, and the CU is predicted using the reference sample of the CU; for example, as described herein, the interpolation filter length of the interpolation filter associated with the CU is determined based on the size of the CU, and when the interpolation filter length of the interpolation filter is not 1, an interpolation reference sample is determined based on the determined interpolation filter length of the interpolation filter and the reference sample of the CU, and the CU is predicted based on the interpolation reference sample; for example, in the merging mode as described herein, the MV of the CU is selected from multiple MV candidates of the CU; for example, using as described herein The selected MV candidate determines the MV associated with the reference sample based on the MV of the CU; for example, as described herein, the reference sample is determined based on the MV associated with the reference sample; for example, as described herein, interpolation is performed using the reference sample (e.g., at an integer position in the reference CU) and an interpolation filter having a determined interpolation filter length to determine the interpolated reference sample (e.g., at a fractional position associated with the reference CU); for example, as described herein, the MV of a 4×4 sub-block in the CU is determined at least based on the MV associated with the CU, and the CU is predicted in affine mode based on the determined MV of the 4×4 sub-block in the CU; for example, as described herein, the MV associated with the first CU is determined based on the first CU size of the first CU. The first interpolation filter length of the first interpolation filter and the second interpolation filter length of the second interpolation filter associated with the second CU based on the size of the second CU; for example, as described herein, when the size of the first CU is greater than the size of the second CU, the first interpolation filter length is determined to be less than the second interpolation filter length; for example, as described herein, the interpolation filter length is determined based on the number of taps indicating the interpolation filter length of the interpolation filter; for example, as described herein, when the interpolation filter length is 1, the interpolation reference sample is determined to be the same as the reference sample; for example, as described herein, the interpolation filter associated with the CU is determined to be an adaptive interpolation filter; and other decoder behaviors related to any of the above.

[0225] The encoder can determine the interpolation filter length of the interpolation filter associated with the CU. For example, as described herein, the encoder (such as according to...) Figure 11 An exemplary encoder 300 operating according to the exemplary method shown may determine the interpolation filter length of the interpolation filter associated with the CU based on the size of the CU. For example, as described herein, the encoder may determine an interpolation reference sample based on the determined interpolation filter length of the interpolation filter and a reference sample of the CU. For example, as described herein, the encoder may predict the CU based on the interpolation reference sample. In some examples as described herein, the encoder may determine the size of the CU and a reference sample of the CU; determine whether to apply an interpolation filter to the reference sample of the CU based on the size of the CU; and predict the CU based on the determination of whether to apply an interpolation filter to the reference sample of the CU. As described herein, the encoder may determine that the interpolation filter length of the interpolation filter is 1 based on the size of the CU, may not apply the interpolation filter to the reference sample based on the determination that the interpolation filter length of the interpolation filter is 1, and may predict the CU using the reference sample of the CU. As described herein, the encoder can determine the interpolation filter length of the interpolation filter associated with the CU based on the size of the CU. When the interpolation filter length is not 1, an interpolation reference sample can be determined based on the determined interpolation filter length of the interpolation filter and a reference sample of the CU, and the CU can be predicted based on the interpolation reference sample. For example, as described herein, the encoder can perform interpolation using a reference sample (e.g., at an integer position in a reference CU) and an interpolation filter having the determined interpolation filter length to determine an interpolation reference sample (e.g., at a fractional position associated with the reference CU). For example, as described herein, for a 4×4 sub-block in the CU, the encoder can determine the MV of the 4×4 sub-block in the CU based at least on the MV associated with the CU, and predict the CU in affine mode and based on the determined MV of the 4×4 sub-block in the CU. For example, as described herein, the encoder can determine the first interpolation filter length of the first interpolation filter associated with the first CU based on the first CU size of the first CU, and determine the second interpolation filter length of the second interpolation filter associated with the second CU based on the second CU size of the second CU. For example, as described herein, when the size of the first CU is greater than the size of the second CU, the length of the first interpolation filter is less than the length of the second interpolation filter. For example, as described herein, the encoder can determine the interpolation filter length based on the number of taps indicating the interpolation filter length. For example, as described herein, when the interpolation filter length is 1, the encoder can determine that the interpolated reference sample is the same as the reference sample. For example, as described herein, the encoder can determine that the interpolation filter associated with the CU is an adaptive interpolation filter.

[0226] Encoding tools and techniques, including one or more of quantization, entropy coding, inverse quantization, inverse transform, and differential coding, can be used to implement, in the encoder, such as Figure 11The methods described herein. These coding tools and techniques can be used to enable one or more of the following: determining the interpolation filter length of an interpolation filter associated with a CU; for example, determining the interpolation filter length of an interpolation filter associated with a CU based on the size of the CU, as described herein; for example, determining an interpolation reference sample based on the determined interpolation filter length of the interpolation filter and a reference sample of the CU, as described herein; for example, predicting the CU based on the interpolation reference sample, as described herein; for example, determining the size of the CU and a reference sample of the CU, as described herein; for example, determining whether to apply an interpolation filter to a reference sample of the CU based on the size of the CU, as described herein; for example, determining whether to apply an interpolation filter to a reference sample of the CU based on the determination herein. Predicting CU; for example, as described herein, determining the interpolation filter length of the interpolation filter to be 1 based on the size of the CU, not applying the interpolation filter to the reference sample based on the determined interpolation filter length to be 1, and predicting the CU using the reference sample of the CU; for example, as described herein, determining the interpolation filter length of the interpolation filter associated with the CU based on the size of the CU, and when the interpolation filter length of the interpolation filter is not 1, determining an interpolation reference sample based on the determined interpolation filter length of the interpolation filter and the reference sample of the CU, and predicting the CU based on the interpolation reference sample; for example, in the merging mode as described herein, selecting the MV of the CU from multiple MV candidates of the CU; for example, using the interpolation filter length as described herein. The selected MV candidate determines the MV associated with the reference sample based on the MV of the CU; for example, as described herein, the reference sample is determined based on the MV associated with the reference sample; for example, as described herein, interpolation is performed using the reference sample (e.g., at an integer position in the reference CU) and an interpolation filter having a determined interpolation filter length to determine the interpolated reference sample (e.g., at a fractional position associated with the reference CU); for example, as described herein, the MV of a 4×4 sub-block in the CU is determined at least based on the MV associated with the CU, and the CU is predicted in affine mode and based on the determined MV of the 4×4 sub-block in the CU; for example, as described herein, the MV associated with the first CU is determined based on the first CU size of the first CU. The first interpolation filter length of the first interpolation filter and the second interpolation filter length of the second interpolation filter associated with the second CU based on the size of the second CU; for example, as described herein, when the size of the first CU is greater than the size of the second CU, the first interpolation filter length is determined to be less than the second interpolation filter length; for example, as described herein, the interpolation filter length is determined based on the number of taps indicating the interpolation filter length of the interpolation filter; for example, as described herein, when the interpolation filter length is 1, the interpolation reference sample is determined to be the same as the reference sample; for example, as described herein, the interpolation filter associated with the CU is determined to be an adaptive interpolation filter; and other encoder behaviors related to any of the above.

[0227] Syntax elements can be inserted into the signaling, for example, to enable the decoder to recognize and execute such... Figure 11 Indications associated with the methods described or used. For example, syntax elements may include information for determining the CU size or the MV of the CU, and / or indications of parameters used by the decoder to perform one or more examples in this document.

[0228] For example, the syntax elements applied at the decoder can be selected and / or applied, such as Figure 11 The method described herein. For example, the decoder may receive information about the size of the CU. The decoder may determine the size of the CU and a reference sample for the CU; determine, based on the size of the CU, whether to apply an interpolation filter to the reference sample of the CU; predict the CU based on the determination of whether to apply the interpolation filter to the reference sample of the CU; determine the interpolation filter length of the interpolation filter associated with the CU based on the size of the CU; determine an interpolation reference sample based on the determined interpolation filter length and the reference sample of the CU; and / or predict the CU based on the interpolation reference sample.

[0229] The encoder can adjust the prediction residual based on one or more examples presented herein. For example, the residual can be obtained by subtracting the predicted video patch from the original image patch. Alternatively, the encoder can predict the video patch based on an interpolated reference sample (or reference sample) obtained as described herein. The encoder can obtain the original image patch and subtract the predicted video patch from it to generate the prediction residual.

[0230] A bitstream or signal may include one or more syntax elements or variations thereof. For example, a bitstream or signal may include syntax elements that indicate any of the information used to determine the size of the CU or the MV of the CU, and / or indications of parameters used by the decoder to perform one or more examples herein.

[0231] Bitstreams or signals may include syntax that conveys information generated according to one or more examples in this document. For example, in the execution of... Figure 11 The example shown generates information or data. The generated information or data can be conveyed in the syntax included in the bitstream or signal.

[0232] This allows the decoder to insert syntax elements into the signal that adapt the residuals in a manner corresponding to those used by the encoder. For example, one or more examples from this paper can be used to generate residuals.

[0233] A method, process, apparatus, medium for storing instructions, medium for storing data, or signal for creating and / or transmitting and / or receiving and / or decoding a bit stream or signal comprising one or more of the said syntax elements or variations thereof.

[0234] A method, process, apparatus, medium for storing instructions, medium for storing data, or signal for creating and / or transmitting and / or receiving and / or decoding according to any of the examples described.

[0235] TVs, set-top boxes, mobile phones, tablets, or other electronic devices may determine the interpolation filter length based on the CU size, according to any of the examples described.

[0236] TVs, set-top boxes, mobile phones, tablets, or other electronic devices may determine the interpolation filter length based on the CU size and display the resulting image, according to any of the examples described (e.g., using a monitor, screen, or other type of display).

[0237] TVs, set-top boxes, mobile phones, tablets, or other electronic devices may select (e.g., using a tuner) a channel to receive signals including encoded images, based on any of the examples described, and determine the interpolation filter length based on the CU size.

[0238] TVs, set-top boxes, mobile phones, tablets, or other electronic devices may receive (e.g., using an antenna) an air signal including an encoded image, according to any of the examples described, and determine the interpolation filter length based on the CU size.

[0239] Although features and elements have been described above in specific combinations, those skilled in the art will understand that each feature or element may be used alone or in any combination with other features and elements. Furthermore, 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 (transmitted over wired or wireless connections) 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 internal hard disks and removable disks), magneto-optical media, and optical media (such as CD-ROM disks and digital versatile optical discs (DVDs)). A processor associated with the software may be used to implement a radio frequency transceiver for a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. A device for video decoding, comprising one or more processors, wherein the one or more processors are configured to: Determine that the coded block uses affine mode for encoding; Based on the determination that the coding block is encoded using the affine mode, the motion vectors (MVs) of the sub-blocks of the coding block are obtained for inter-frame prediction of the sub-blocks; Determine the size of the coded block; Based on the MV precision associated with the MV of the sub-block, an interpolation filter associated with the sub-block is determined to be applied to obtain a reference sample for the inter-frame prediction of the sub-block, wherein the MV precision and the length of the interpolation filter vary based on the size of the coding block; Based on the size of the coding block, an interpolation filter for the inter-frame prediction of the sub-block is selected from a plurality of interpolation filters of different sizes, such that a shorter length of the interpolation filter is used based on a larger coding block size. The reference sample is obtained based on the MV of the sub-block, the MV precision associated with the MV, and the length of the interpolation filter; Predict the sub-block based on the reference sample; as well as The encoded block is decoded based on the prediction of the sub-block.

2. The device of claim 1, wherein the MV precision is obtained from a plurality of MV precisions, wherein the reference sample is a second reference sample, wherein the second reference sample is associated with a fractional position of a reference block associated with the sub-block, and wherein the second reference sample is obtained based on a first reference sample associated with an integer position of the reference block.

3. The apparatus of claim 1, wherein the interpolation filter for the inter-frame prediction of the sub-block is selected such that a longer interpolation filter is used based on the smaller size of the coding block.

4. An apparatus for video encoding, comprising one or more processors, wherein the one or more processors are configured to: Determine that the coded block uses affine mode for encoding; Based on the determination that the coding block is encoded using the affine mode, the motion vectors (MVs) of the sub-blocks of the coding block are obtained for inter-frame prediction of the sub-blocks; Determine the size of the coded block; Based on the MV precision associated with the MV of the sub-block, an interpolation filter associated with the sub-block is determined to be applied to obtain a reference sample for the inter-frame prediction of the sub-block, wherein the MV precision and the length of the interpolation filter vary based on the size of the coding block; Based on the size of the coding block, an interpolation filter for the inter-frame prediction of the sub-block is selected from a plurality of interpolation filters of different sizes, such that a shorter length of the interpolation filter is used based on a larger coding block size. The reference sample is obtained based on the MV of the sub-block, the MV precision associated with the MV, and the length of the interpolation filter; Predict the sub-block based on the reference sample; as well as The coded block is encoded based on the prediction of the sub-block.

5. The device of claim 4, wherein the MV precision is obtained from a plurality of MV precisions, wherein the reference sample is a second reference sample, wherein the second reference sample is associated with a fractional position of a reference block associated with the sub-block, and wherein the second reference sample is obtained based on a first reference sample associated with an integer position of the reference block.

6. A method for video decoding, comprising: Determine that the coded block uses affine mode for encoding; Based on the determination that the coding block is encoded using the affine mode, the motion vectors (MVs) of the sub-blocks of the coding block are obtained for inter-frame prediction of the sub-blocks; Determine the size of the coded block; Based on the MV precision associated with the MV of the sub-block, an interpolation filter associated with the sub-block is determined to be applied to obtain a reference sample for the inter-frame prediction of the sub-block, wherein the MV precision and the length of the interpolation filter vary based on the size of the coding block; Based on the size of the coding block, an interpolation filter for the inter-frame prediction of the sub-block is selected from a plurality of interpolation filters of different sizes, such that a shorter length of the interpolation filter is used based on a larger coding block size. The reference sample is obtained based on the MV of the sub-block, the MV precision associated with the MV, and the length of the interpolation filter; Predict the sub-block based on the reference sample; as well as The encoded block is decoded based on the prediction of the sub-block.

7. The method of claim 6, wherein the MV precision is obtained from a plurality of MV precisions, wherein the reference sample is a second reference sample, wherein the second reference sample is associated with a fractional position of a reference block associated with the sub-block, and wherein the second reference sample is obtained based on a first reference sample associated with an integer position of the reference block.

8. The method of claim 6, wherein the length of the interpolation filter is indicated by the number of taps of the interpolation filter.

9. The method of claim 6, wherein the interpolation filter comprises an adaptive interpolation filter.

10. The method of claim 7, wherein the length of the interpolation filter is 1, and the second reference sample is the same as the first reference sample.

11. A method for video encoding, comprising: Determine that the coded block uses affine mode for encoding; Based on the determination that the coding block is encoded using the affine mode, the motion vectors (MVs) of the sub-blocks of the coding block are obtained for inter-frame prediction of the sub-blocks; Determine the size of the coded block; Based on the MV precision associated with the MV of the sub-block, an interpolation filter associated with the sub-block is determined to be applied to obtain a reference sample for the inter-frame prediction of the sub-block, wherein the MV precision and the length of the interpolation filter vary based on the size of the coding block; Based on the size of the coding block, an interpolation filter for the inter-frame prediction of the sub-block is selected from a plurality of interpolation filters of different sizes, such that a shorter length of the interpolation filter is used based on a larger coding block size. The reference sample is obtained based on the MV of the sub-block, the MV precision associated with the MV, and the length of the interpolation filter; Predict the sub-block based on the reference sample; as well as The coded block is encoded based on the prediction of the sub-block.

12. The method of claim 11, wherein the MV precision is obtained from a plurality of MV precisions, wherein the reference sample is a second reference sample, wherein the second reference sample is associated with a fractional position of a reference block associated with the sub-block, and wherein the second reference sample is obtained based on a first reference sample associated with an integer position of the reference block.

13. The method of claim 11, wherein the length of the interpolation filter is indicated by the number of taps of the interpolation filter.

14. The method of claim 11, wherein the interpolation filter comprises an adaptive interpolation filter.

15. The method of claim 12, wherein the length of the interpolation filter is 1, and the second reference sample is the same as the first reference sample.

16. A computer-readable medium comprising instructions for causing one or more processors to perform the method according to any one of claims 6 to 15.

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