Film Grain Pattern Reduction

Abstract

Systems, methods, and means for performing film grain pattern reduction are disclosed. A device may obtain film grain pattern priority information associated with a plurality of film grain patterns for a block. The device may determine a reduced set of film grain patterns from the plurality of film grain patterns based on the film grain pattern priority information on which to perform a film grain pattern analysis. The device may perform the film grain pattern analysis on the reduced set of film grain patterns. The device may select a film grain pattern from the reduced set of film grain patterns to apply to pixel components of the block based on the film grain pattern analysis. The device may apply the selected film grain pattern to the pixel components of the block.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of European Provisional Patent Application No. 22305490.9, filed April 8, 2022, the disclosure of which is incorporated herein by reference in its entirety. [Background technology]

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

[0003] Systems, methods, and means for performing film grain pattern reduction are disclosed. An exemplary device (e.g., a device for video decoding) may include a processor configured to perform one or more actions. The device may obtain film grain pattern priority information associated with a plurality of film grain patterns for a block. The device may determine a reduced set of film grain patterns from the plurality of film grain patterns on which to perform film grain pattern analysis based on the film grain pattern priority information. The device may perform film grain pattern analysis on the reduced set of film grain patterns. The device may select a film grain pattern from the reduced set of film grain patterns to apply to pixel components of the block based on the film grain pattern analysis. The device may apply the selected film grain pattern to the pixel components of the block.

[0004] A device may receive a supplemental enhancement information (SEI) message comprising a list of parameters. The device may determine that a reduced set of film grain patterns comprises film grain patterns associated with a number of parameters that are first listed in the SEI message. Each film grain pattern of the plurality of film grain patterns may be associated with a corresponding weight. The device may determine that the reduced set of film grain patterns comprises a number of film grain patterns of the plurality of film grain patterns that have a maximum corresponding weight.

[0005] The corresponding weight for a given film grain pattern may be based on at least one of: a sum of intensity interval sizes associated with the given film grain pattern, a number of pixels to which the given film grain pattern is applied, a scaling factor associated with the given film grain pattern, an intensity value associated with the given film grain pattern, or a weighted average of parameter values ​​associated with the given film grain pattern.

[0006] A first film grain pattern of the reduced set of film grain patterns may be associated with a first set of film grain parameters. A second film grain pattern of the reduced set of film grain patterns may be associated with a second set of film grain parameters. The device may receive a supplemental enhancement information (SEI) message indicating a third set of film grain parameters. The device may determine a first difference between the first set of film grain parameters and the third set of film grain parameters and a second difference between the second set of film grain parameters and the third set of film grain parameters. On a condition that the first difference is less than the second difference, the device may select the first film grain pattern to apply to pixel components of the block. On a condition that the second difference is less than the first difference, the device may select the second film grain pattern to apply to pixel components of the block.

[0007] The device may determine a scaling factor associated with the selected film grain pattern. The device may apply the scaling factor to the selected film grain pattern. The film grain pattern priority information may indicate rules for prioritizing the multiple film grain patterns and / or a maximum number of film grain patterns that the reduced set of film grain patterns may include. The pixel components of the block may be pixel intensity components.

[0008] A method (e.g., for video decoding) may involve obtaining film grain pattern priority information associated with a plurality of film grain patterns for a block. The method may involve determining a reduced set of film grain patterns from the plurality of film grain patterns based on the film grain pattern priority information for performing a film grain pattern analysis. The method may involve performing a film grain pattern analysis on the reduced set of film grain patterns. The method may involve selecting a film grain pattern from the reduced set of film grain patterns for applying to pixel components of the block based on the film grain pattern analysis. The method may involve applying the selected film grain pattern to the pixel components of the block.

[0009] The method may involve receiving a supplemental extension information (SEI) message comprising a list of parameters. Determining the reduced set of film grain patterns based on the film grain pattern priority information may involve determining that the reduced set of film grain patterns comprises film grain patterns associated with a number of parameters that are listed first in the SEI message. Each film grain pattern of the plurality of film grain patterns may be associated with a corresponding weight. Determining the reduced set of film grain patterns based on the film grain pattern priority information may involve determining that the reduced set of film grain patterns comprises a number of film grain patterns of the plurality of film grain patterns that have a maximum corresponding weight.

[0010] The corresponding weight for a given film grain pattern may be based on at least one of: a sum of intensity interval sizes associated with the given film grain pattern, a number of pixels to which the given film grain pattern is applied, a scaling factor associated with the given film grain pattern, an intensity value associated with the given film grain pattern, or a weighted average of parameter values ​​associated with the given film grain pattern.

[0011] A first film grain pattern of the reduced set of film grain patterns may be associated with a first set of film grain parameters. A second film grain pattern of the reduced set of film grain patterns may be associated with a second set of film grain parameters. The method may involve receiving a supplemental enhancement information (SEI) message indicating a third set of film grain parameters. Performing a film grain pattern analysis on the reduced set of film grain patterns may involve determining a first difference between the first set of film grain parameters and the third set of film grain parameters, and a second difference between the second set of film grain parameters and the third set of film grain parameters.

[0012] Selecting a film grain pattern to apply to pixel components of the block based on the film grain pattern analysis may involve selecting a first film grain pattern to apply to the pixel components of the block on condition that the first difference is less than the second difference, and selecting a second film grain pattern to apply to the pixel components of the block on condition that the second difference is less than the first difference. The method may involve determining a scaling factor associated with the selected film grain pattern. The method may involve applying the scaling factor to the selected film grain pattern.

[0013] An exemplary device (e.g., a device for video encoding) may include a processor configured to perform one or more actions: The device may generate a set of film grain parameters associated with a video image. The device may obtain film grain pattern priority information. The device may generate a supplemental enhancement information (SEI) message associated with the video image. The SEI message may include a set of film grain parameters associated with the video image and the film grain pattern priority information. The device may encode the video image to generate an encoded video image. The device may send the SEI message and the encoded video image.

[0014] The film grain pattern priority information may indicate a reduced set of film grain parameters. The reduced set of film grain parameters may include a number of film grain parameters that are listed first in the SEI message. Each film grain parameter in the set of film grain parameters may be associated with a corresponding weight. The film grain pattern priority information may indicate a reduced set of film grain parameters. The reduced set of film grain parameters may include a number of film grain parameters that have a maximum corresponding weight.

[0015] The systems, methods, and means described herein may involve a decoder. In some embodiments, the systems, methods, and means described herein may involve an encoder. In some embodiments, the systems, methods, and means described herein may involve a signal (e.g., from an encoder and / or received by a decoder). A computer-readable medium may include instructions for causing one or more processors to perform the methods described herein. A computer program product may include instructions that, when executed by one or more processors, may cause the one or more processors to perform the methods described herein. [Brief description of the drawings]

[0016] [Figure 1A] FIG. 1 is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented. [Figure 1B] 1B is a system diagram illustrating an example wireless transmit / receive unit (WTRU) that may be used within the communications system shown in FIG. 1A, according to one embodiment. [Figure 1C] FIG. 1B is a system diagram illustrating an example radio access network (RAN) and an example core network (CN) that may be used within the communication system shown in FIG. 1A, according to one embodiment. [Figure 1D] FIG. 1B is a system diagram illustrating a further exemplary RAN and a further exemplary CN that may be used within the communication system shown in FIG. 1A, according to one embodiment. [Diagram 2] 1 illustrates an exemplary video encoder. [Diagram 3] 1 illustrates an exemplary video decoder. [Figure 4] 1 illustrates an example of a system in which various aspects and embodiments may be implemented. [Diagram 5] 2 illustrates an example of a grain model in video coding. [Figure 6] 1 shows an example block diagram of frame grain usage in a video coding framework. [Figure 7] 1 shows an example of a film grain compositing block diagram. [Figure 8] 1 shows an example of a diagram of pattern adaptation. [Figure 9] 1 illustrates an exemplary film grain supplemental enhancement information (SEI) modification. [Figure 10] 1 shows an example of video transcoding with film grain metadata conversion. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] A more detailed understanding may be had from the following description, given by way of example in conjunction with the accompanying drawings, in which:

[0018] 1A is a diagram illustrating an example communications system 100 in which one or more disclosed embodiments may be implemented. Communications system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcasts, etc., to multiple wireless users. Communications system 100 may enable multiple wireless users to access such content through sharing of system resources, including wireless bandwidth. For example, the communications system 100 may use one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero-tail unique-word DFT-Spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multicarrier (FBMC), and the like.

[0019] 1A, communications 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, although it will be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d, any of which may be referred to as a "station" and / or "STA," may be configured to transmit and / or receive wireless signals and may include user equipment (UE), mobile stations, fixed or mobile subscriber units, subscription-based units, wireless paging, mobile phones, personal digital assistants (PDAs), smartphones, laptops, netbooks, personal computers, wireless sensors, hotspots or Mi-Fi devices, Internet of Things (loT) devices, watches or other wearable head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., for remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in an industrial and / or automated processing chain context), consumer electronics devices, devices operating in commercial and / or industrial wireless networks, and the like. Any of the WTRUs 102a, 102b, 102c, and 102d may be referred to interchangeably as a UE.

[0020] The communication system 100 may also include a base station 114a and / or a base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106 / 115, the Internet 110, and / or other networks 112. By way of example, the base stations 114a, 114b may be a base station transceiver station (BTS), a Node B, an eNode B, a Home Node B, a Home eNode B, a gNB, an NR Node B, a site controller, an access point (AP), a wireless router, etc. Although the base stations 114a, 114b are each illustrated as a single element, it will be understood that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0021] The base station 114a may be part of the RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, etc. The base station 114a and / or the base station 114b may be configured to transmit and / or receive wireless signals on one or more carrier frequencies, which may be referred to as cells (not shown). These frequencies may be licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide wireless service coverage for a particular geographic area, which may be relatively fixed or may change over time. A cell may be further divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, i.e., one transceiver for each sector of the cell. In one embodiment, the base station 114a may employ multiple-input multiple output (MIMO) technology and may utilize multiple transceivers for each sector of the cell, for example, using beamforming to transmit and / or receive signals in a desired spatial direction.

[0022] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d via an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0023] More specifically, as noted above, the communications system 100 may be a multiple access system, but may use one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, the base stations 114a and the WTRUs 102a, 102b, 102c in the RAN 104 / 113 may implement a radio technology, such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 115 / 116 / 117 using wideband CDMA (WCDMA). WCDMA may include communications 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 ​​Uplink Packet Access (HSUPA).

[0024] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A) and / or LTE-Advanced Pro (LTE-A Pro).

[0025] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology, such as New Radio (NR) radio access, which may establish the air interface 116 using NR technology.

[0026] In one embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may implement LTE radio access and NR radio access together, e.g., using dual connectivity (DC) principles. Thus, the air interface utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions transmitted to / from multiple types of base stations (e.g., eNBs and gNBs).

[0027] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement a wireless technology such as IEEE 802.11 (i.e., Wireless Fidelity, WiFi), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access, WiMAX), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), or the like.

[0028] 1A may be, for example, a wireless router, a Home NodeB, a Home eNodeB, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a localized area, such as an office, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a road, etc. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology, such as IEEE 802.11, to establish a wireless local area network (WLAN). In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology, such as IEEE 802.15, to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may establish a picocell or a femtocell using a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.). As shown in FIG. 1A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not need to access the Internet 110 via the CN 106 / 115.

[0029] The RAN 104 / 113 may communicate with the CN 106 / 115, which may be any type of network configured to provide voice, data, application, and / or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have various quality of service (QoS) requirements, such as, for example, different throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. The CN 106 / 115 may provide call control, billing services, mobile location-based services, prepaid calling, Internet connectivity, video distribution, etc., and / or perform high level security functions such as user authentication. Although not shown in FIG. 1A, it will be appreciated that the RAN 104 / 113 and / or the CN 106 / 115 may communicate directly or indirectly with other RANs that use the same RAT as the RAN 104 / 113 or a different RAT. For example, in addition to being connected to the RAN 104 / 113, which may utilize NR radio technology, the CN 106 / 115 may also communicate with another RAN (not shown) using GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or WiFi radio technology.

[0030] The CN 106 / 115 may also act as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network providing plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the transmission control protocol (TCP), user datagram protocol (UDP), and / or the internet protocol (IP) of the TCP / IP Internet protocol suite. The networks 112 may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, the networks 112 may include another CN connected to one or more RANs, which may use the same RAT as the RANs 104 / 113 or a different RAT.

[0031] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU 102c shown in FIG. 1A may be configured to communicate with a base station 114a, which may employ a cellular-based wireless technology, and a base station 114b, which may employ an IEEE 802 wireless technology.

[0032] Figure 1B is a system diagram illustrating an example WTRU 102. As shown in Figure 1B, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and / or other peripherals 138. It will be understood that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0033] The processor 118 may 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. The processor 118 may perform signal coding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although FIG. 1B illustrates the processor 118 and the transceiver 120 as separate components, it will be understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0034] The transmit / receive element 122 may be configured to transmit or receive signals to or from a base station (e.g., base station 114a) over the air interface 116. For example, in one embodiment, the transmit / receive element 122 may be an antenna configured to transmit and / or receive RF signals. In one embodiment, the transmit / receive element 122 may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit / receive element 122 may be configured to transmit and / or receive both RF and light signals. It will be appreciated that the transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0035] 1B as a single element, the WTRU 102 may include any number of transmit / receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0036] The transceiver 120 may be configured to modulate signals transmitted by the transmit / receive element 122 and demodulate signals received by the transmit / receive element 122. As mentioned above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers to enable the WTRU 102 to communicate via multiple RATs, such as, for example, NR and IEEE 802.11.

[0037] The processor 118 of the WTRU 102 may be coupled to and may receive user-entered data from a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light-emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. In addition, the processor 118 may access information from and store data in any type of suitable memory, such as non-removable memory 130 and / or removable memory 132. The 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. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, etc. In other embodiments, the processor 118 may access information from and store data in memory that is not physically located on the WTRU 102, such as on a server or home computer (not shown).

[0038] The processor 118 may receive power from the power source 134 and may be configured to distribute and / or control the power to other components in the WTRU 102. The power source 134 may be any suitable device for providing power to the WTRU 102. For example, the power source 134 may include one or more dry batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0039] 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) regarding the current location of the WTRU 102. In addition to, or in lieu of, information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) over the air interface 116 and / or determine its location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may obtain location information by way of any suitable position determination method while remaining consistent with an embodiment.

[0040] The processor 118 may further be coupled to other peripherals 138, which may include one or more software and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or videos), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, a Bluetooth® module, a frequency modulated (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a virtual reality and / or augmented reality (VR / AR) device, an activity tracker, and the like. The peripherals 138 may include one or more sensors, which may be one or more of a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor, a geolocation sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0041] The WTRU 102 may include a full-duplex radio where transmission and reception of some or all of the signals associated with a particular subframe (e.g., for both the UL (e.g., for transmission) and the downlink (e.g., for reception) may be parallel and / or simultaneous. The full-duplex radio may include an interference management unit to reduce and or substantially eliminate self-interference via either hardware (e.g., a choke) or signal processing via a processor (e.g., via a separate processor (not shown) or via the processor 118). In one embodiment, the WRTU 102 may include a half-duplex radio for transmission and reception of either some or all of the signals (e.g., associated with a particular subframe for either the UL (e.g., for transmission) or the downlink (e.g., for reception)).

[0042] 1C is a system diagram illustrating the RAN 104 and the CN 106, according to one embodiment. As mentioned above, the RAN 104 may employ E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also communicate with the CN 106.

[0043] The RAN 104 may include eNodeBs 160a, 160b, 160c, although it will be understood that the RAN 104 may include any number of eNodeBs while remaining consistent with an embodiment. The eNodeBs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In an embodiment, the eNodeBs 160a, 160b, 160c may implement MIMO technology. Thus, the eNodeB 160a may, for example, use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0044] Each of the eNodeBs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and / or DL, etc. As shown in FIG 1C, the eNodeBs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0045] 1C 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 illustrated as part of the CN 106, it will be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0046] The MME 162 may be connected to each of the eNodeBs 162a, 162b, 162c in the RAN 104 via an S1 interface and may function as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, activating / deactivating bearers, selecting a particular serving gateway during initial attachment of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and / or WCDMA.

[0047] The SGW 164 may be connected to each of the eNodeBs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to and from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring the user plane during inter-eNodeB handover, triggering paging when DL data is available to the WTRUs 102a, 102b, 102c, and managing and storing the context of the WTRUs 102a, 102b, 102c.

[0048] The SGW 164 may be connected to a PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0049] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0050] Although the WTRU is depicted in FIGS. 1A-1D as a wireless terminal, in certain representative embodiments, it is contemplated that such a terminal may use a wired communications interface (e.g., temporarily or permanently) with the communications network.

[0051] In an exemplary embodiment, the other network 112 may be a WLAN.

[0052] A WLAN in infrastructure Basic Service Set (BSS) mode may have an Access Point (AP) of the BSS and one or more stations (STAs) associated with the AP. The AP may have access or interface to a Distribution System (DS) or another type of wired / wireless network that carries traffic into and / or out of the BSS. Traffic originating from outside the BSS to the STA may arrive through the AP and be delivered to the STA. Traffic originating from the STA to a destination outside the BSS may be sent to the AP to be delivered to the respective destination. Traffic between STAs within the BSS may be sent, for example, through the AP, where the source STA may send traffic to the AP, which may deliver the traffic to the destination STA. Traffic between STAs within the BSS may be considered and / or referred to as peer-to-peer traffic. Peer-to-peer traffic may be sent between (e.g., directly between) the source STA and the destination STA using a direct link setup (DLS). In certain representative embodiments, the DLS may use 802.11e DLS or 802.11z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and STAs (e.g., all of the STAs) within or using the IBSS may communicate directly with each other. The IBSS mode of communication may be referred to herein as an "ad-hoc" communication mode.

[0053] When using an 802.11ac infrastructure mode of operation or a similar mode of operation, an AP may transmit a beacon on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., a 20 MHz wide bandwidth) or a width that is dynamically set via signaling. The primary channel may be the operating channel of the BSS, but may be used by STAs to establish a connection with the AP. In certain representative embodiments, for example, in an 802.11 system, Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA) may be implemented. With CSMA / CA, STAs (e.g., all STAs), including the AP, may sense the primary channel. If the primary channel is sensed / detected and / or determined to be busy by a particular STA, the particular STA may back off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0054] A High Throughput (HT) STA may use a 40 MHz wide channel for communication, which may be formed, for example, through a combination of a primary 20 MHz channel and adjacent or non-adjacent 20 MHz channels.

[0055] A Very High Throughput (VHT) STA may support 20 MHz, 40 MHz, 80 MHz, and / or 160 MHz wide channels. A 40 MHz and / or 80 MHz channel may be formed by combining multiple contiguous 20 MHz channels. A 160 MHz channel may be formed by combining eight contiguous 20 MHz channels or by combining two non-contiguous 80 MHz channels, which may be referred to as an 80+80 configuration. For the 80+80 configuration, after channel encoding, the data may pass through a segment parser that may split the data into two streams. Inverse Fast Fourier Transform (IFFT) processing and time domain processing may be performed separately on each stream. The streams may be mapped to two 80 MHz channels and the data may be transmitted by the transmitting STA. At the receiver of the receiving STA, the operations described above for the 80+80 configuration may be reversed and the combined data may be transmitted to the Medium Access Control (MAC).

[0056] Sub-1 GHz operating modes are supported by 802.11af and 802.11ah. Channel operating bandwidths and carriers are reduced in 802.11af and 802.11ah compared to those used in 802.11n and 802.11ac. 802.11af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in TV White Space (TVWS) spectrum, and 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah may support meter-type control / machine-type communication, such as MTC devices in macro coverage areas. MTC devices may have limited capabilities, including certain capabilities, for example, support for (e.g., support only for) certain and / or limited bandwidths. MTC devices may include batteries with above-threshold battery life (e.g., to maintain very long battery life).

[0057] WLAN systems that may support multiple channels and channel bandwidths, such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include a channel that may be designated as a primary channel. The primary channel may have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be configured and / or limited by the STAs among all STAs operating in the BSS that support the smallest bandwidth operating mode. In an 802.11ah embodiment, the primary channel may be 1 MHz wide for STAs (e.g., MTC-type devices) that support (e.g., only) the 1 MHz mode, even if the AP and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or Network Allocation Vector (NAV) configuration may depend on the status of the primary channel. For example, if the primary channel is active due to a STA (that only supports the 1 MHz mode of operation) transmitting to the AP, the entire available frequency band may be considered active even though most of the frequency band may remain dormant and available.

[0058] In the United States, the available frequency bands that can be used by 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 bandwidth available for 802.11ah is 6MHz to 26MHz depending on the country code.

[0059] 1D is a system diagram illustrating the RAN 113 and the CN 115, according to one embodiment. As mentioned above, the RAN 113 may employ NR radio technology and communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 113 may also communicate with the CN 115.

[0060] The RAN 113 may include gNBs 180a, 180b, 180c, although it will be understood that the RAN 113 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In an embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, the gNBs 180a, 108b may utilize beamforming to transmit signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a may transmit and / or receive wireless signals to and from the WTRU 102a, for example, using multiple antennas. In one embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on an unlicensed spectrum, while the remaining component carriers may be on a licensed spectrum. In one embodiment, the gNBs 180a, 180b, 180c may implement Coordinated Multi-Point (CoMP) technology. For example, the WTRU 102a may receive coordinated transmissions from the gNBs 180a and 180b (and / or gNB 180c).

[0061] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with scalable numerology. For example, the OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or transmission time intervals (TTIs) of different or scalable lengths (e.g., including different numbers of OFDM symbols and / or lasting different lengths of absolute time).

[0062] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c without accessing another RAN (e.g., eNodeBs 160a, 160b, 160c, etc.). In a standalone configuration, the WTRUs 102a, 102b, 102c may utilize one or more of the gNBs 180a, 180b, 180c as mobility anchor points. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using signals in unlicensed bands. In a non-standalone configuration, the WTRUs 102a, 102b, 102c may communicate with and connect to a gNB 180a, 180b, 180c while also communicating with and connecting to another RAN, such as an eNodeB 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement DC principles to communicate with one or more gNBs 180a, 180b, 180c and one or more eNodeBs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNodeBs 160a, 160b, 160c may act as mobility anchors for the WTRUs 102a, 102b, 102c, and the gNBs 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0063] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and / or DL, support for network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data to user plane functions (UPFs) 184a, 184b, routing of control plane information to access and mobility management functions (AMFs) 182a, 182b, etc. As shown in FIG. 1D , the gNBs 180a, 180b, 180c may communicate with each other via an Xn interface.

[0064] 1D 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 illustrated as part of the CN 115, it will be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0065] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may function as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, supporting network slicing (e.g., handling different PDU sessions with different requirements), selecting a particular SMF 183a, 183b, managing registration areas, terminating NAS signaling, mobility management, etc. Network slicing may be used by the AMF 182a, 182b to customize the CN support of the WTRUs 102a, 102b, 102c based on the type of service utilizing the WTRUs 102a, 102b, 102c. For example, different network slices may be established for different use cases such as services relying on ultra-reliable low latency (URLLC) access, services relying on enhanced massive mobile broadband (eMBB) access, services for machine type communication (MTC) access, etc. The AMF 162 may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that employ other radio technologies such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies such as WiFi.

[0066] The SMFs 183a, 183b may be connected to the AMFs 182a, 182b in the CN 115 via an N11 interface. The SMFs 183a, 183b may also be connected to the UPFs 184a, 184b in the CN 115 via an N4 interface. The SMFs 183a, 183b may select and control the UPFs 184a, 184b and configure the routing of traffic through the UPFs 184a, 184b. The SMFs 183a, 183b may perform other functions such as managing and allocating UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0067] The UPFs 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPFs 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, etc.

[0068] The CN 115 may facilitate communication with other networks. For example, the CN 115 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between the CN 115 and the PSTN 108. In addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to local data networks (DNs) 185a, 185b through the UPFs 184a, 184b via an N3 interface to the UPFs 184a, 184b and an N6 interface between the UPFs 184a, 184b and the DNs 185a, 185b.

[0069] 1A-1D and the corresponding description thereof, one or more or all of the functions described herein with respect to one or more of the WTRUs 102a-d, base stations 114a-b, eNodeBs 160a-c, MME 162, SGW 164, PGW 166, gNBs 180a-c, AMFs 182a-b, UPFs 184a-b, SMFs 183a-b, DNs 185a-b, and / or any other devices described herein may be performed by one or more emulation devices (not shown). The emulation devices may be one or more devices configured to emulate one or more or all of the functions described herein. For example, the emulation devices may be used to test other devices and / or to simulate network and / or WTRU functions.

[0070] The emulation device may be designed to implement one or more tests of other devices in a lab environment and / or an operator network environment. For example, one or more emulation devices may implement one or more or all functions while fully or partially implemented and / or deployed as part of a wired and / or wireless communication network to test other devices in the communication network. One or more emulation devices may perform one or more or all functions while temporarily implemented / deployed as part of a wired and / or wireless communication network. The emulation device may be directly coupled to another device for testing purposes and / or may use terrestrial wireless communication to perform the testing.

[0071] The one or more emulation devices may perform one or more functions, inclusive, while not being implemented / deployed as part of a wired and / or wireless communication network. For example, the emulation devices may be utilized in test scenarios in a test lab and / or in an undeployed (e.g., test) wired and / or wireless communication network to implement 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 (which may include, for example, one or more antennas) may be used by the emulation devices to transmit and / or receive data.

[0072] This application describes various aspects, including tools, features, examples, models, techniques, and the like. Many of these aspects are described with specificity and often in a potentially limiting manner to at least illustrate their individual characteristics. However, this is for purposes of clarity of description and does not limit the applicability or scope of the aspects. In fact, all of the different aspects may be combined and interchanged to provide further aspects. Moreover, these aspects may likewise be combined and interchanged with aspects described in prior applications.

[0073] Aspects described and contemplated in this application may be implemented in many different forms. While Figures 5-10 described herein may provide some examples, other examples are contemplated. Discussion of Figures 5-10 is not intended to limit the scope of implementations. At least one of the above aspects generally relates to video encoding and decoding, and at least one other aspect generally relates to transmitting a generated or encoded bitstream. These and other aspects may be implemented as a method, an apparatus, a computer-readable storage medium having stored thereon instructions for encoding or decoding video data according to any of the described methods, and / or a computer-readable storage medium having stored thereon a bitstream generated according to any of the described methods.

[0074] In this application, the terms "reconstructed" and "decoded" may be used interchangeably, the terms "pixel" and "sample" may be used interchangeably, and the terms "image", "picture", and "frame" may be used interchangeably.

[0075] Various methods are described herein, each of which includes one or more steps or acts for achieving the described method. Unless a specific order of steps or acts is required for proper operation of the method, the order and / or use of specific steps and / or acts may be modified or combined. Additionally, terms such as "first", "second", etc. may be used in various embodiments to modify elements, components, steps, operations, etc., such as, for example, "first decoding" and "second decoding". The use of such terms does not imply a modified ordering of operations, unless specifically required. Thus, in this embodiment, the first decoding need not be performed before the second decoding, but may occur, for example, before, during, or during a period of overlap with the second decoding.

[0076] Various methods and other aspects described herein may be used to modify modules, such as the decoding modules, of the video encoder 200 and decoder 300, as shown in Figures 2 and 3. Moreover, the subject matter disclosed herein may apply to any type, format, or version of video coding, whether existing or developed in the future, and to any extensions of such standards and recommendations, whether described in a standard or recommendation, for example. Unless otherwise indicated or technically impossible, aspects described herein may be used individually or in combination.

[0077] In the embodiments described in this application, various numerical values ​​are used, such as 0, 1, 2, 3, 4, 5, 8, 16, 32, 64, 256, etc. These and other specific values ​​are for purposes of illustrating the embodiments, and the described aspects are not limited to these specific values.

[0078] 2 illustrates an exemplary video encoder. Although variations of the exemplary encoder 200 are contemplated, the encoder 200 is described below for clarity purposes without describing all possible variations.

[0079] Before encoding, the video sequence may undergo pre-encoding processing (201), such as applying a color transformation to the input color picture (e.g., converting from RGB 4:4:4 to YCbCr 4:2:0) or performing a remapping of the input picture components to obtain a signal distribution more resilient to compression (e.g., using histogram equalization of one of the color components). Metadata may be associated with the pre-processing and attached to the bitstream. The pre-processing may include film grain analysis, where grain parameters may be estimated. This may include noise removal, for example to facilitate bitrate reduction. Grain estimation may be performed (e.g., or may be added manually) before encoding. The encoding may reduce noise (e.g., due to quantization) and grain. In an example, a denoiser may remove grain before encoding and after estimating grain parameters.

[0080] In the encoder 200, a picture is coded by the encoder elements, as described below. The picture to be coded is divided (202) and processed, for example, in coding units (CUs). Each unit is coded, for example, using either intra-mode or inter-mode. When a unit is coded in intra-mode, it performs intra prediction (260). In inter-mode, motion estimation (275) and motion compensation (270) are performed. The encoder decides (205) whether to use intra-mode or inter-mode to code the unit, and indicates the decision, for example, by a prediction mode flag. A prediction residual is calculated (210), for example, by subtracting the prediction block from the original image block.

[0081] The prediction residual is then transformed (225) and quantized (230). The quantized transform coefficients, as well as the motion vectors and other syntax elements, are entropy coded (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., the residual is coded directly without applying the transform or quantization processes.

[0082] The encoder decodes the coded block to provide a reference for further prediction. To decode the prediction residual, the quantized transform coefficients are dequantized (240) and inverse transformed (250). The decoded prediction residual and the predicted block are combined (255) to reconstruct an image block. An in-loop filter (265) is applied to the reconstructed picture to perform, for example, deblocking / Sample Adaptive Offset (SAO) filtering to reduce coding artifacts. The filtered image is stored in a reference picture buffer (280).

[0083] 3 illustrates an example of a video decoder. In the exemplary decoder 300, the bitstream is decoded by a decoder element as described below. The video decoder 300 generally performs a decoding path that is the inverse of the encoding path described in FIG. 2. Furthermore, the encoder 200 generally performs video decoding as part of the video data encoding.

[0084] In particular, the decoder input includes a video bitstream, which may be generated by the video encoder 200. The bitstream is first entropy decoded (330) to obtain transform coefficients, motion vectors, and other coded information. Picture partition information indicates how the picture is partitioned. Thus, the decoder may partition the picture according to the decoded picture partition information (335). To decode the prediction residual, the transform coefficients are dequantized (340) and inverse transformed (350). The decoded prediction residual and the predicted block are combined (355) to reconstruct an image block. The predicted block may be obtained from intra prediction (360) or from motion-compensated prediction (i.e., inter prediction) (375) (370). An in-loop filter (365) is applied to the reconstructed image. The filtered image is stored in a reference picture buffer (380).

[0085] The decoded picture may further undergo post-decoding processing (385), such as an inverse color transform (e.g., converting from YCbCr 4:2:0 to RGB 4:4:4), or inverse remapping, which performs the inverse of the remapping process performed in the pre-encoding processing (201). The post-decoding processing may use metadata derived in the pre-encoding processing and signaled in the bitstream. In an embodiment, the decoded image (e.g., after application of an in-loop filter (365) and / or after post-decoding processing (385), if post-decoding processing is used) may be sent to a display device for rendering to a user.

[0086] FIG. 4 illustrates an example of a system in which various aspects and embodiments described herein may be implemented. System 400 may be embodied as a device including various components described below and configured to implement one or more of the aspects described herein. Examples of such devices include various electronic devices, such as, but not limited to, personal computers, laptop computers, smartphones, tablet computers, digital multimedia set-top boxes, digital television receivers, personal video recording systems, connected appliances, and servers. The elements of system 400, singly or in combination, may be embodied in a single integrated circuit (IC), multiple ICs, and / or separate components. For example, in at least one embodiment, the processing and encoder / decoder elements of system 400 are distributed across multiple ICs and / or separate components. In various embodiments, system 400 is communicatively coupled to one or more other systems or other electronic devices, for example, via a communication bus or through dedicated input and / or output ports. In various embodiments, system 400 is configured to implement one or more of the aspects described herein.

[0087] The system 400 is configured to execute instructions loaded therein, for example, to implement various aspects described herein. The system 400 includes at least one processor 410. The processor 410 may include embedded memory, input / output interfaces, and various other circuits known in the art. The system 400 includes at least one memory 420 (e.g., a volatile memory device and / or a non-volatile memory device). The system 400 includes a storage device 440, which may include 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, magnetic disk drive, and / or optical disk drive. The storage device 440 may include, by way of non-limiting example, an internal storage device, an attached storage device (including removable and non-removable storage devices), and / or a network-accessible storage device.

[0088] The system 400 includes an encoder / decoder module 430 configured to process data to provide, for example, 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 may be included within a device to perform encoding and / or decoding functions. As is known, a device may include one or both of an encoding module and a decoding module. It is noted that the encoder / decoder module 430 may be implemented as a separate element of the system 400 or may be incorporated within the processor 410 as a combination of hardware and software known to those skilled in the art.

[0089] Program code to be loaded into the processor 410 or the encoder / decoder 430 to implement various aspects described herein may be stored in the storage device 440 and then loaded into the memory 420 for execution by the processor 410. According to various embodiments, one or more of the processor 410, the memory 420, the storage device 440, and the encoder / decoder module 430 may store one or more of various items during performance of the processes described herein. Such stored items may include, but are not limited to, input video, decoded video or portions of decoded video, bitstreams, matrices, variables, and intermediate or final results from the processing of equations, expressions, operations, and computational logic.

[0090] In some embodiments, memory internal to the processor 410 and / or the encoder / decoder module 430 is used to store instructions and provide working memory for processing required during encoding or decoding. However, in other embodiments, memory external to the processing device (e.g., the processing device can be either the processor 410 or the encoder / decoder module 430) is used for one or more of these functions. The external memory may be the memory 420 and / or the storage device 440, e.g., dynamic volatile memory and / or non-volatile flash memory. In some embodiments, an external non-volatile flash memory is used, for example, to store the television's operating system. In at least one embodiment, a high-speed external dynamic volatile memory, such as a RAM, is used as working memory for video encoding and decoding operations.

[0091] Inputs to the elements of system 400 may be provided through various input devices, as shown in block 445. Such input devices may include, but are not limited to, (i) a radio frequency (RF) section that receives, for example, RF signals transmitted over the air by a broadcast station, (ii) a component (COMP) input terminal (or set of COMP input terminals), (iii) a universal serial bus (USB) input terminal, and / or (iv) a High Definition Multimedia Interface (HDMI) input terminal. Other examples include composite video, not shown in FIG. 4.

[0092] In various embodiments, the input devices of block 445 have associated respective input processing elements as known in the art. For example, the RF section may be associated with appropriate elements to (i) select a desired frequency (also referred to as selecting a signal or band-limiting a signal to a frequency band), (ii) downconvert the selected signal, (iii) band-limit again to a narrower frequency band to select a signal frequency band, which in a particular embodiment may be referred to (for example) as a channel, (iv) demodulate the downconverted and band-limited signal, (v) perform error correction, and / or (vi) demultiplex to select a desired stream of data packets. The RF section of various embodiments includes one or more elements for performing these functions, such as a frequency selector, a signal selector, a band limiter, a channel selector, a filter, a downconverter, a demodulator, an error corrector, and a demultiplexer. The RF section may include, for example, a tuner that performs various of these functions, including downconverting a received signal to a lower frequency (e.g., an intermediate frequency or a frequency close to baseband) or to baseband. In one embodiment of a set-top box, the RF section and its associated input processing elements perform frequency selection by receiving, filtering, downconverting, and filtering again to a desired frequency band an RF signal transmitted over a wired (e.g., cable) medium. Various embodiments rearrange the order of the above-described (and other) elements, remove some of these elements, and / or add other elements to perform similar or different functions. Adding elements can include inserting elements between existing elements, such as, for example, inserting amplifiers and analog-to-digital converters. In various embodiments, the RF section includes an antenna.

[0093] The USB and / or HDMI terminals may include respective interface processors for connecting the system 400 to other electronic devices via USB and / or HDMI connections. It should be appreciated that various aspects of the input processing, e.g., Reed-Solomon error correction, may be implemented, for example, in a separate input processing IC or in the processor 410, as desired. Similarly, aspects of the USB or HDMI interface processing may be implemented, for example, in a separate interface IC or in the processor 410, as desired. The demodulated, error corrected, and demultiplexed streams are provided to various processing elements, including, for example, the processor 410 and an encoder / decoder 430 operating in combination with memory and storage elements that process the data streams as desired for presentation on an output device.

[0094] The various elements of system 400 may be provided within an integrated housing in which the various elements may be interconnected and transmit data between them using a suitable connection arrangement 425, such as an internal bus known in the art, including an Inter-IC (I2C) bus, hardwired, and printed circuit boards.

[0095] System 400 includes a communication interface 450 that enables communication with other devices over a communication channel 460. Communication interface 450 may include, but is not limited to, a transceiver configured to transmit and receive data over communication channel 460. Communication interface 450 may include, but is not limited to, a modem or a network card, and communication channel 460 may be implemented in a wired and / or wireless medium, for example.

[0096] Data is streamed or otherwise provided to system 400 in various embodiments using a wireless network such as a Wi-Fi network, e.g., IEEE 802.11 (IEEE refers to the Institute of Electrical and Electronics Engineers). The Wi-Fi signal in these embodiments is received via communication channel 460 and communication interface 450 adapted for Wi-Fi communication. Communication channel 460 in these embodiments is typically connected to an access point or router that provides access to external networks, including the Internet, to enable streaming applications and other over-the-top communications. Other embodiments provide streamed data to system 400 using a set-top box that delivers data via an HDMI connection in input block 445. Still other embodiments provide streamed data to system 400 using an RF connection in input block 445. As noted above, various embodiments provide data in a non-streaming manner. Additionally, various embodiments use wireless networks other than Wi-Fi, e.g., cellular networks or Bluetooth networks.

[0097] The system 400 can provide output signals to various output devices, including a display 475, speakers 485, and other peripheral devices 495. The display 475 in various embodiments includes, for example, one or more of a touch screen display, an organic light emitting diode (OLED) display, a curved display, and / or a foldable display. The display 475 can be for a television, a tablet, a laptop, a mobile phone, or other device. Furthermore, the display 475 can be integrated with other components (e.g., as in a smart phone) or can be separate (e.g., an external monitor for a laptop). The other peripheral devices 495 in various embodiments include one or more of a stand-alone digital video disc (or digital versatile disc) (DVD for both terms), a disc player, a stereo system, and / or a lighting system. Various embodiments use one or more peripheral devices 495 that provide functionality based on the output of the system 400. For example, a disc player performs the function of playing the output of the system 400.

[0098] In various embodiments, control signals are communicated between system 400 and display 475, speaker 485, or other peripheral devices 495 using signaling such as AV.Link, Consumer Electronics Control (CEC), or other communication protocols that allow control between devices with or without user intervention. Output devices may be communicatively coupled to system 400 via dedicated connections through respective interfaces 470, 480, and 490. Alternatively, output devices may be connected to system 400 via communication interface 450 using communication channel 460. Display 475 and speaker 485 may be integrated into a single unit with other components of system 400 in an electronic device such as, for example, a television. In various embodiments, display interface 470 includes a display driver, such as, for example, a timing controller (TCon) chip.

[0099] Display 475 and speakers 485 may alternatively be separate from one or more of the other components, for example if the RF portion of input 445 is part of a separate set-top box. In various embodiments where display 475 and speakers 485 are external components, output signals may be provided via dedicated output connections including, for example, an HDMI port, a USB port, or a COMP output.

[0100] These embodiments may be performed by the processor 410, or by computer software implemented by hardware, or by a combination of hardware and software. As a non-limiting example, these embodiments may be implemented by one or more integrated circuits. The memory 420 may be of any type suitable for the technology environment, and may be implemented using any suitable data storage technology, such as, as non-limiting examples, optical memory devices, magnetic memory devices, semiconductor-based memory devices, fixed memories, and removable memories. The processor 410 may be of any type suitable for the technology environment, and may include, as non-limiting examples, one or more of a microprocessor, a general-purpose computer, a special-purpose computer, and a processor based on a multi-core architecture.

[0101] Various implementations involve decoding. As used herein, "decoding" may encompass all or a portion of the processes performed on a received encoded sequence to result in a final output suitable for, for example, a display. In various embodiments, such processes include processes typically performed by a decoder, such as one or more of entropy decoding, inverse quantization, inverse transform, and differential decoding. In various examples, such processes may also or alternatively include processes performed by a decoder of various implementations described herein, such as, for example, a device may obtain film grain pattern priority information associated with a plurality of film grain patterns for a block. The device may determine, based on the film grain pattern priority information, from the plurality of film grain patterns, a reduced set of film grain patterns on which to perform a film grain pattern analysis. The device may perform the film grain pattern analysis on the reduced set of film grain patterns. The device may select a film grain pattern from the reduced set of film grain patterns to apply to pixel components of the block based on the film grain pattern analysis. The device may apply the selected film grain pattern to pixel components of the block, etc.

[0102] As a further example, in one embodiment, "decoding" refers to only entropy decoding, while in another embodiment, "decoding" refers to only differential decoding, while in another embodiment, "decoding" refers to a combination of entropy and differential decoding. Whether the phrase "decoding process" is intended to refer specifically to a subset of operations or to the broader decoding process as a whole will be clear based on the context of the specific description and will be well understood by one of ordinary skill in the art.

[0103] Various implementations involve encoding. Similar to the above discussion regarding "decoding," "encoding" as used herein can encompass, for example, all or a portion of the processes performed on an input video sequence to produce an encoded bitstream. In various embodiments, such processes include one or more of processes typically performed by an encoder, such as partitioning, differential encoding, transforming, quantizing, and entropy encoding. In various examples, such processes also or instead include processes performed by an encoder in various implementations described herein, such as, for example, a device may generate a set of film grain parameters associated with a video image. The device may obtain film grain pattern priority information. The device may generate a supplemental enhancement information (SEI) message associated with the video image. The SEI message may include a set of film grain parameters associated with the video image and the film grain pattern priority information. The device may encode the video image to generate an encoded video image. The device may send the SEI message and the encoded video image.

[0104] As a further example, in one embodiment, "encoding" refers to only entropy encoding, while in another embodiment, "encoding" refers to only differential encoding, while in another embodiment, "encoding" refers to a combination of differential and entropy encoding. Whether the phrase "encoding process" is intended to refer specifically to a subset of operations or to the broader encoding process as a whole will be clear based on the context of the specific description and will be well understood by one of ordinary skill in the art.

[0105] It should be noted that the coding syntax for syntax elements used herein, e.g., number of intensity intervals, number of model values, grain parameters, grain identities, scaling factors, etc., are descriptive terms and therefore do not exclude the use of other syntax element names.

[0106] Where a figure is presented as a flow diagram, it should be understood that the figure also provides a block diagram of the corresponding apparatus. Similarly, where a figure is presented as a block diagram, it should be understood that the figure also provides a flow diagram of the corresponding method / process.

[0107] The implementations and aspects described herein may be implemented, for example, in a method or process, an apparatus, a software program, a data stream, or a signal. Even if discussed in the context of only a single form of implementation (e.g., discussed only as a method), the implementation of the discussed features may also be implemented in other forms (e.g., an apparatus or a program). An apparatus may be implemented, for example, in appropriate hardware, software, and firmware. A method may be implemented, for example, in a processor, which generally refers to a processing device and includes, for example, a computer, a microprocessor, an integrated circuit, or a programmable logic device. Processors also include, for example, communication devices such as computers, cellular phones, portable / personal digital assistants ("PDAs"), and other devices that facilitate communication of information between end users.

[0108] References to "one example" or "an example" or "one implementation" or "an implementation," as well as other variations thereof, mean that a particular feature, structure, characteristic, etc. described in connection with an embodiment is included in at least one embodiment. Thus, the appearances of the phrases "in one example" or "in an example" or "in one implementation" or "in an implementation" in various places throughout this application, as well as any other variations, are not necessarily all referring to the same embodiment.

[0109] Additionally, the application may refer to "determining" various information. Determining information may include, for example, one or more of estimating information, calculating information, predicting information, or retrieving information from a memory. Obtaining may include receiving, retrieving, constructing, generating, and / or determining.

[0110] Additionally, the application may refer to "accessing" various information. Accessing information may include, for example, one or more of receiving information, retrieving information (e.g., from a memory), storing information, moving information, copying information, calculating information, determining information, predicting information, or estimating information.

[0111] Additionally, the application may refer to "receiving" various information. Receiving, like "accessing," is intended to be a broad term. Receiving information may include, for example, one or more of accessing information or retrieving information (e.g., from a memory). Furthermore, "receiving" generally involves in some manner an operation, 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.

[0112] For example, in the case of "A / B," "A and / or B," and "at least one of A and B," it should be understood that the use of any of the following " / ," "and / or," and "at least one of" is intended to encompass the selection of only the first enumerated alternative (A), or the selection of only the second enumerated alternative (B), or the selection of both alternatives (A and B). As a further example, in the case of "A, B, and / or C" and "at least one of A, B, and C," such language is intended to encompass the selection of only the first enumerated alternative (A), or the selection of only the second enumerated alternative (B), or the selection of only the third enumerated alternative (C), or the selection of only the first and second enumerated alternatives (A and B), or the selection of only the first and third enumerated alternatives (A and C), or the selection of only the second and third enumerated alternatives (B and C), or the selection of all three alternatives (A and B and C). This can be expanded as many times as the items listed, as would be apparent to one of ordinary skill in this and related arts.

[0113] Also, as used herein, the term "signaling" means, among other things, indicating something to a corresponding decoder. The encoder signal may include, for example, the number of intensity intervals, the number of model values, grain parameters, grain identification, scaling factors, etc. In this way, in one embodiment, the same parameters are used on both the encoder and decoder sides. Thus, for example, the encoder may transmit a particular parameter to the decoder so that the decoder can use the same particular parameter (explicit signaling). Conversely, if the decoder already has the particular parameter as well as other parameters, it may use signaling without transmitting, simply to allow the decoder to know and select the particular parameter (implicit signaling). By avoiding transmitting any actual functionality, bit savings are realized in various embodiments. It should be understood that signaling may be achieved in various ways. For example, in various embodiments, one or more syntax elements, flags, etc. are used to signal information to a corresponding decoder. Although the above relates to the verb form of the term "signal", the term "signal" may also be used as a noun in this specification.

[0114] As will be apparent to one of ordinary skill in the art, implementations may generate a variety of signals formatted to carry information that may be, for example, stored or transmitted. Information may include, for example, instructions for performing a method or data generated by one of the described implementations. For example, a signal may be formatted to carry a bit stream of the described embodiments. Such a signal may be formatted, for example, as an electromagnetic wave (e.g., using a radio frequency portion of the spectrum) or as a baseband signal. Formatting may include, for example, encoding a data stream and modulating a carrier wave with the encoded data stream. The information that the signal carries may be, for example, analog information or digital information. The signal may be transmitted by a variety of different wired or wireless links, as is well known. The signal may be stored in, accessed from, or received from a processor-readable medium.

[0115] Many examples are described herein. Features of the examples may be provided alone or in any combination across various claim categories and types. Furthermore, examples may include one or more of the features, devices, or aspects described herein, alone or in any combination across various claim categories and types. For example, features described herein may be implemented in a bitstream or signal that includes information generated as described herein. The information may enable a decoder to decode the bitstream, encoder, bitstream, and / or decoder according to any of the described embodiments. For example, features described herein may be implemented by generating and / or transmitting and / or receiving and / or decoding a bitstream or signal. For example, features described herein may be implemented as a method, process, apparatus, medium storing instructions, medium storing data, or signal. For example, features described herein may be implemented by a TV, a set-top box, a mobile phone, a tablet, or other electronic device that performs the decoding. A TV, set-top box, mobile phone, tablet, or other electronic device may display (e.g., using a monitor, screen, or other type of display) the resulting image (e.g., an image from the residual reconstruction of the video bitstream). A TV, set-top box, mobile phone, tablet, or other electronic device may receive a signal that includes the encoded image and perform decoding.

[0116] Features associated with video compression, distribution, and / or rendering are provided herein. Film grain modeling may include using film grain metadata and / or implementation adaptation (e.g., to reduce complexity). Film grain metadata and / or implementation adaptation may be used for adaptation between different codecs and / or different models.

[0117] Film grain synthesis may be performed in a post-decoding process.

[0118] Film grain metadata may be defined through a supplemental extension information (SEI) message for a coded video bitstream (e.g., a generic supplemental extension information (VSEI) message). In an example, film grain syntax may be integrated into a frame header and film grain metadata may be part of the core codec specification. Support for film grain may be specified in different ways. Depending on the codec and / or model, different syntaxes and semantics may be used. Since different models may be used (as shown in FIG. 5), the compositing process and film grain mixing may be defined differently.

[0119] FIG. 5 shows an example of a grain model in video coding.

[0120] Features associated with film grain post-processing with respect to memory and the like are described herein.

[0121] FIG. 6 shows an example of a block diagram of film grain usage in a video coding framework. As shown in FIG. 6, at 500, pre-processing may be performed (e.g., input video data may be pre-processed). At 501, film grain estimation may be performed (e.g., using the input video data and the filtered video from the output of a pre-processing block). At 502, the filtered video and film grain parameters (e.g., from the output of a film grain estimation block) may be encoded. At 503, the encoded bitstream and film grain parameters in the form of a film grain characteristics (FGC) SEI message (e.g., from the output of a coding block) may be decoded. At 504, film grain synthesis may be performed (e.g., film grain may be added to a decoded image).

[0122] FIG. 7 illustrates an example of a film grain synthesis block diagram. As shown in FIG. 7, SEI film grain synthesis can be used. SEI film grain synthesis can involve using 8×8 sub-blocks. In an example, different sub-block sizes (any sub-block size) can be used. The decoder can output a decoded frame and film grain characteristics SEI (e.g., film grain parameters). For color channels (e.g., luma, chroma Cb, chroma Cr, etc. color channels), appropriate grain parameters can be selected (e.g., based on film grain parameters in the SEI message) based on image block averages (e.g., 8×8 block averages, 16×16 block averages, 8×1 block averages, 5×2 block averages, pixel averages, etc.). 8×8 (e.g., or 16×16, etc.) grain sub-blocks can be selected from a pre-computed film grain database with film grain patterns defined for larger block sizes, which can be deblocked (e.g., optionally deblocked) to reduce blocking artifacts in the grain generation. Grain may be added / blended into the image. Selection may be based on the SEI and the average block intensity value as described herein. The SEI may define multiple grain parameters to use (e.g., one for each intensity interval).

[0123] In the SEI frequency filtering mode, to generate the grain pattern, the process may involve a pseudo-random generator to generate a 64x64 block and an inverse frequency transform (e.g., an inverse discrete cosine transform (IDCT)). In the auto-regressive mode, the 64x64 block may be calculated using a random number generator. Different grain patterns may be obtained by different model parameters defined in the SEI. In an example, the number of different patterns may be one per component. This process may be pre-computed once per frame or once at initialization. The process may be pre-computed in a read-only memory (ROM) and loaded into the execution memory. In an example, if the grain is present in the original video, the encoder may estimate the grain parameters in a pre-processing step (e.g., by analyzing the grain). The parameters may be added manually. For example, the parameters may be added by adding an SEI message with the parameters (e.g., the correct parameters) to the stream, or by providing the appropriate parameters to the encoder, which may add the SEI.

[0124] In an SEI film grain generator (e.g., a film grain synthesizer compatible with the FGC SEI message), one or more patterns (e.g., multiple patterns) may be defined per image using parameters defined in the film grain characteristics SEI message. The maximum number of available patterns (e.g., simultaneously available patterns) per frame may be fixed and the value may be high. For example, 10 different patterns per frame may be defined in the SEI message. The 10 patterns may be loaded into memory (e.g., fast memory) to address frame output frequency constraints. A larger amount of memory may be required to store the patterns. Reducing the maximum number of patterns used by a frame may reduce the cost of the film grain synthesizer.

[0125] An exemplary framework is provided herein for reducing the number of noise patterns (e.g., film grain patterns) that are different from those defined in the film grain characteristics SEI message. The synthesized film grain can use a reduced number of noise patterns that should make the film grain generation match (e.g., visually) with the specified patterns (e.g., all specified patterns).

[0126] At the encoder (e.g., at the encoder stage), the film grain parameters may be modified, for example, to generate an output SEI message that includes a reduced number of film grain patterns (e.g., a smaller number of film grain patterns, or a subset of the film grain patterns determined based on the SEI message). The modification may be applied between the film grain analysis and the SEI (e.g., writing to the bitstream). For example, a film grain analysis may be performed on the input video. The film grain analysis may generate input film grain parameters. The input film grain parameters may be adapted, and an SEI may be generated and encoded using the adapted film grain parameters. The output (e.g., the output bitstream) may include the output film grain parameters (e.g., may be included in the FGC SEI message). In an example, if the film grain parameters are provided as an input to the encoder (e.g., manually estimated), the film grain parameters may not be estimated at the encoder. In such a case, the film grain analysis may be skipped, and the input film grain parameters may be provided to the encoder.

[0127] During the transcoding stage (e.g., between encoding and decoding), the SEI may be modified, at the decoder the SEI may be modified, or at the film grain combiner the SEI may be interpreted and applied.

[0128] [Table 1]

[0129] Table 1 may define the film grain characteristics SEI message. Table 1 may define parameters of grain, such as where a grain generation pattern is defined based on those model parameters, for an intensity interval (e.g., all intensity intervals) of component values ​​of an input image.

[0130] Exemplary semantics of the different parameters are summarized in Table 2, where c is a component index and can vary from 0 to 2, with 0 being the luminance channel and 1 and 2 being the chrominance channel.

[0131] [Table 2]

[0132] For film grain processing, the pattern to use may be determined for a location (e.g., each location) having intensity I[c] based on the intensity interval that I[c] falls into. In an example, if multi-grain generation is allowed, the intervals may be allowed to overlap, I[x] may fall into multiple intervals, and multiple grains may be generated. If multi-grain generation is not allowed, the intervals may not overlap.

[0133] The process used to synthesize the film grain may depend on the values ​​of the film grain characteristic parameters, the intensity I[c], and / or the pixel intensity. A film grain synthesizer may be used.

[0134] If the grain pattern to be used depends on pixel intensities (e.g., pixel component intensities), a mapping lookup table (LUT) can be used to map the value of I[c] to the grain pattern to be used. In an example, a dense LUT can be used that can define the correspondence of values ​​(e.g., all values) of the signal. If the bit depth is high, this can involve (e.g., require) a large amount of memory to hold the LUT, and subsampling can be used. For example, the LUT can be limited to 256 values, which can correspond to 8-bit sampling. In such a case, the signal can be scaled to 8 bits before the LUT by truncating or rounding the high bit depth values ​​to a lower bit depth.

[0135] The SEI may define which pattern fg_comp_model_value[c][i] should be used for each intensity interval [fg_intensity_interval_lower_bound[c][i], fg_intensity_interval_upper_bound[c][i]]. I[c] may be the intensity of the image component c (e.g., luminance or chrominance value) of the current block or pixel (e.g., pixel component). To speed up the composition, a LUT may be pre-computed to map the intensity (e.g., image block value) to the model parameter index used. As defined in Table 2, the model parameters may define the scaling factor fg_comp_model_value[c][i][0] and the grain pattern fg_comp_model_value[c][i][1...5] (e.g., fg_comp_model_value[c][i][j], j varies from 1 to 5). This LUT grain_param_id[c][I] may be generated by processing, for a component c (e.g., each component c), a model parameter with index k and an intensity interval defined by fg_intensity_interval_[lower / upper]_bound[c][k]. For an interval intensity value (e.g., each intensity value), a LUT value may be set for model parameter index k based on:

[0136] [Table 3]

[0137] grain_param_id may represent the index of the parameter to use for the current intensity value, as defined in the SEI (e.g., if grain_param_id[c][i]=p, then the grain parameter fg_comp_model_value[c][p] may be used).

[0138] To apply film grain to pixel values ​​(e.g., all pixel values ​​or pixel component values) of an input frame I[c][x][y], the process may include one or more of the following (e.g., the process may be applied block-wise on an average value of I[c] over the current block): An intensity value may be extracted. An index of the parameter may be read from the LUT. A scaling factor may be read from the parameter. Grain may be added to the pixel (e.g., or all pixels or pixel components of the block) based on the model parameters corresponding to the scaling factor and the index, as shown below.

[0139] [Table 4]

[0140] add_grain() may be a grain generation function, as described herein.

[0141] Mapping image intensities to a reduced set of patterns (e.g., a subset of the patterns determined based on the SEI message, or a set of patterns having fewer patterns than the patterns determined based on the SEI message) may be implemented in a decoder, encoder, and / or transcoder, as described herein.

[0142] A mapping of image intensities to a reduced set of patterns may be provided. The SEI may define different characteristics for each intensity interval. As defined herein, the parameter fg_comp_model_value[c][i][j], where j varies from 1 to 5, may have an effect on the grain pattern, and the parameter fg_comp_model_value[c][i][0] may be a scaling factor and may take different values ​​(e.g., without significant effect on complexity).

[0143] To limit the complexity, the maximum number of allowed different patterns per component c may be defined as max_pattern_num[c]. The minimum number of allowed different patterns per component c may be defined as max_pattern_num[c]={1,1,1} (e.g., one for each color component). In an example, the constraint may be relaxed to have more available patterns (e.g., {3,2,2}), where more patterns (e.g., 3) are allocated to the luminance component than the other components (e.g., 2,2). The value {1,1,1} may be used with film grain compositing, which uses one (e.g., only one) grain pattern per component. The process of defining the mapping LUT may be modified as described herein.

[0144] FIG. 8 shows an example of pattern adaptation.

[0145] As shown in FIG. 8, the input grain parameters defined in the SEI may be analyzed and adapted to the pattern number. The pattern to use for any given intensity interval may be selected from the adaptive patterns, for example by selecting the closest one in terms of difference (e.g., sum of absolute differences) between the input parameters and the parameters associated with the adaptive pattern. The index for the selected pattern may be stored in a LUT for the intensity values ​​of the intensity interval (e.g., every intensity value), and the scaling factor may be adapted and stored in a scaling factor LUT, as shown below. In an example, the scaling factor may be mapped. The scaling factor may define a gain to be applied to the grain pattern. The scaling factor and the adapted pattern may be defined in the SEI (e.g., in the same parameter set). For one or more intervals (e.g., two given intervals), the parameters may define the same pattern and different scaling factors (e.g., two different scaling factors). In an example, the number of different patterns may be reduced and the scaling factor may change. The scaling factor may be the same as the input, or may be adapted to the pattern, for example if the pattern changes for a given intensity interval.

[0146] [Table 5]

[0147] grain_scaling_factor[3][] may be a LUT of scaling coefficients for the pattern-adapted intensities (e.g., each intensity). max_pattern_num may be the maximum number of patterns per component that may be used in the pattern reduction process. grain_pattern_params may be the adapted grain pattern parameters with the same semantics as fg_comp_model_value.

[0148] preprocess_patterns may be a process that analyzes the SEI parameters and reduces the number of different patterns to the maximum number of available patterns per component. preprocess_patterns may output the results to grain_pattern_params. This process may copy the max_pattern_num[c] first pattern parameters of fg_comp_model_value[c] to grain_pattern_params[c]. The process of selecting parameters (e.g., most important parameters) and ordering the parameters may be left to the discretion of the content creator, who may compress the video content and create the original film grain SEI characteristics. The process of selecting parameters (e.g., most important parameters) and ordering the parameters may be performed using weighting techniques, as described herein.

[0149] select_best_pattern may be a film grain pattern analysis performed on the reduced set (e.g., a subset of film grain patterns, or a smaller set of film grain patterns) to select a best film grain pattern from among the subset of film grain patterns. select_best_pattern may involve mapping an input SEI index to an index related to an adapted film grain pattern (e.g., a reduced set of film grain patterns or a subset of film grain patterns). The selection may be based on a difference between the input parameters and the adapted model parameters (e.g., model parameters associated with the reduced set of film grain patterns). The adaptive parameters associated with the smallest difference may be selected. For example, a first set of adapted parameters may have a first difference from the input parameters, and a second set of adapted parameters may have a second difference from the input parameters. In this case, the film grain pattern associated with the first set of adaptive parameters may be selected provided that the first difference is less than the second difference. Similarly, the film grain pattern associated with the second set of adaptive parameters may be selected provided that the second difference is less than the first difference. The difference may be calculated as the maximum difference between the parameter values ​​(e.g., each parameter value), the sum of absolute differences, the sum of squared differences, or any other difference operation. The parameters to be considered for calculating the difference may not include scaling parameters (e.g., scaling factors).

[0150] adapt_scale may be a process that adapts the scaling factors for the adapted pattern. If the grain parameters change, the scaling factors may be adapted based on the parameter modifications (e.g., to give a similar grain look). In an example, the scaling factor adaptation process may include a direct copy of the input scaling factors as defined by fg_comp_model_value[c][k][0].

[0151] To apply film grain to pixel values ​​(e.g., all pixel values ​​or pixel component values) of an input frame I[c][x][y], the process may be similar to other processes described in this specification (e.g., the process may be applied block-by-block for the average value of I[c] over the current block), except that a grain_scaling_factor[c][val] LUT may be used in place of the first parameter fg_comp_model_value[c][k][0] and a model parameter grain_pattern_params[c] may be used in place of the input parameter fg_comp_model_value[c], as shown below.

[0152] [Table 6]

[0153] Features related to selecting the pattern to use are provided. Examples of the process preprocess_patterns that remaps the input film grain characteristics fg_comp_model_value[c] to a reduced set of patterns are described herein. The reduced set of patterns (e.g., a subset of film grain patterns, or a smaller set of film grain patterns) may be selected based on film grain priority information (e.g., film grain patterns associated with the first listed pattern parameters, or the most heavily weighted pattern parameters). For example, as shown above, the reduced set of patterns may include a copy of the max_pattern_num[c] first pattern parameters of fg_comp_model_value[c] in grain_pattern_params[c]. If max_pattern_num[c] is equal to or greater than the number of distinct input parameters, adaptation may not be used (e.g., may not be required) and a direct copy may be used.

[0154] Features associated with copying SEI parameters (e.g., first SEI parameters) are provided herein. A first unique pattern may be used. As explained above, the first parameter of fg_comp_model_value[c][k] may be a scaling factor and may be discarded from the comparison function (e.g., the scaling factor may be treated separately). Copying the first pattern may include filling the first different max_pattern_num[c] model parameters of fg_comp_model_value[c] into grain_pattern_params[c]. The intensity intervals may be scanned (e.g., until a maximum number of patterns is reached). The process may involve checking (e.g., first check) whether the pattern parameters are present (e.g., already present) in the selected model parameters (e.g., different intervals may have the same grain parameters but different scaling factors). If the model parameters are already present in the selected pattern, the next interval may be processed. If the model parameters are not already present in the selected pattern, the input parameters may be copied to the selected grain pattern and the number of patterns found may be incremented.

[0155] [Table 7]

[0156] num_patterns[c] may be the number of new patterns currently found, and grain_pattern_params[c] may be the selected model parameters.

[0157] In an example, the patterns may be selected based on the weighting values ​​(e.g., the pattern with the largest corresponding weight may be selected). For each pattern, the parameters may be stored in a list and the corresponding weight may be increased. The list may be sorted based on the weights (e.g., most important patterns first) and the first max_pattern_num[c] parameter may be selected. The weighting may be the sum of the interval sizes (e.g., intensity interval sizes) as shown below. The weighting may be related to the number of affected pixels. The patterns affecting the largest number of pixels may be kept to reduce the perceived correction of the pattern reduction process. In an example, the weighting may include other characteristics such as the scaling factor, the average of the scaling factor, the maximum intensity value of the interval, the maximum average intensity of the interval, and / or the actual number of affected pixels (e.g., pixel components) in each interval (e.g., this may involve analysis of the complete input image, such as a histogram calculation, prior to pattern selection).

[0158] [Table 8]

[0159] A feature(s) related to computing a set of patterns is provided herein. In an example, the selected patterns may be adapted to reduce the impact on grain synthesis of reducing the number of patterns. For example, the set of patterns may be initialized by one of the processes described herein. The adapted set of patterns (e.g., a reduced set of patterns) may be computed by combining input model parameters. For example, grain_pattern_params[c] may be obtained (e.g., as described herein). For each input model parameter fg_comp_model_value[c][k] that may be mapped to a pattern grain_pattern_params[c][p], a combination of these input model parameters may be used to compute an adapted parameter adapted_grain_pattern_params[c][p]. For a scalar parameter (e.g., each scalar parameter), the combination may be, for example, an average, a weighted average based on interval size, an intensity value, a scaling factor, etc.

[0160] [Table 9]

[0161] adapted_grain_pattern_params[c] may be the grain pattern parameters calculated as a weighted average of the input model parameters based on previous pattern selection.

[0162] The adapted grain pattern parameters may be calculated (e.g., directly) from the input fg_comp_model_value[c] values ​​based on a K-means process (e.g., to calculate k values ​​as the centroid of m input values, where m>k).

[0163] The pattern may be the result of an optimization process in which a cost function is minimized (e.g., the sum of Euclidean distances between statistical moments of different orders, frequency bandwidths, etc. between the grain pattern resulting from the new parameters and the merged grain pattern). The cost function may include weighting based on pattern usage. The optimization may be based on the difference between rendering on the full picture with the new parameters and rendering on the full picture with the original parameters.

[0164] Features related to modifying the SEI are provided herein. An output SEI may be initialized with the input parameters. The number of different patterns may not be part of the SEI. A device may generate a set of film grain parameters associated with a video image. A device may generate an SEI message associated with a video image. The SEI message may include a set of film grain parameters associated with the video image. A device may modify an SEI message associated with a video image. The modified SEI message may include a reduced set (e.g., a subset or smaller set) of film grain parameters associated with the video image. A device may encode a video image to generate an encoded video image. The device may send the modified SEI message and the encoded video image. A parameter value may be modified for an intensity interval (e.g., for every intensity interval k).

[0165] Features related to generating an SEI are provided herein. An output SEI may be initialized with the input parameters. The device may generate a set of film grain parameters associated with the video image. The film grain parameters may include associated priority information, such as weights calculated as described herein. The device may generate an SEI message associated with the video image. The SEI message may include a set of film grain parameters associated with the video image. The SEI message may include priority information associated with each film grain parameter. Such priority information may be the order in which the parameters are included in the SEI message. For example, the most important (e.g., highest weighted parameters) may be listed first in the SEI message. The device may send the SEI message and the encoded video image.

[0166] Features related to modifying an SEI are provided herein. An output SEI may be initialized with the input parameters. The device may generate a set of film grain parameters associated with the video image. The SEI message may include the set of film grain parameters associated with the video image. The device may modify the SEI message associated with the video image. Priority information (e.g., weights as described herein) may be calculated for each grain parameter. The device may modify the SEI message associated with the video image. The modified SEI message may include priority information associated with each film grain parameter. The priority information may be, for example, the order in which the parameters are included in the SEI message. For example, the most important parameters (e.g., parameters with the highest weights) may be included first in the SEI message (e.g., at the beginning of the SEI message). The device may send the modified SEI message and the encoded video image.

[0167] The index may be selected as described herein.

[0168] [Table 10]

[0169] The grain parameters may be from the adaptive parameters corresponding to the index.

[0170] [Table 11]

[0171] The scaling factor may be adapted.

[0172] [Table 12]

[0173] The SEI may be converted to other film grain metadata formats.

[0174] 9 shows an example of film grain SEI modification. If the film grain parameters are adapted to reduce the number of different patterns (e.g., to one single pattern), the patterns may be converted to (e.g., some other) film grain metadata that uses a single film grain pattern (e.g., the metadata format shown in FIG. 9).

[0175] AFGS1 (AOMedia Film Grain Synthesis Model) may be an autoregressive film grain synthesis model. The model may be indicated using a registered or unregistered user data SEI message.

[0176] The film grain characteristics SEI message may be converted to AFGS1 compatible metadata. For example, the SEI message may be converted after reducing the number of different patterns to one (e.g., a single pattern), converting the scaling factors (e.g., which are typically step functions) to piecewise linear functions, and / or adapting the model parameters from the SEI format to the AFGS1 format (e.g., if a frequency model is used in the SEI format). If a frequency model is used in the SEI format, a conversion (e.g., a special conversion) may be performed. If an auto-regression mode is used in the SEI, the conversion may be easier (e.g., simpler) because the film grain in AFGS1 uses an auto-regression model to generate the grain pattern.

[0177] 10 shows an example of video transcoding with film grain metadata transformation. In the transcoding framework, a first stream including film grain characteristics SEI may be transformed into a second stream including film grain metadata. In such a case, the film grain characteristics may be signaled in the second stream in AFGS1 metadata format and / or embedded in the stream, as shown in FIG. 10.

[0178] Systems, methods, and means for performing film grain pattern reduction are disclosed. An exemplary device (e.g., a device for video decoding) may include a processor configured to perform one or more actions. The device may obtain film grain pattern priority information associated with a plurality of film grain patterns for a block. The device may determine a reduced set of film grain patterns from the plurality of film grain patterns on which to perform film grain pattern analysis based on the film grain pattern priority information. The device may perform film grain pattern analysis on the reduced set of film grain patterns. The device may select a film grain pattern from the reduced set of film grain patterns to apply to pixel components of the block based on the film grain pattern analysis. The device may apply the selected film grain pattern to the pixel components of the block.

[0179] A device may receive a supplemental enhancement information (SEI) message comprising a list of parameters. The device may determine that a reduced set of film grain patterns comprises film grain patterns associated with a number of parameters that are first listed in the SEI message. Each film grain pattern of the plurality of film grain patterns may be associated with a corresponding weight. The device may determine that the reduced set of film grain patterns comprises a number of film grain patterns of the plurality of film grain patterns that have a maximum corresponding weight.

[0180] The corresponding weight for a given film grain pattern may be based on at least one of: a sum of intensity interval sizes associated with the given film grain pattern, a number of pixels to which the given film grain pattern is applied, a scaling factor associated with the given film grain pattern, an intensity value associated with the given film grain pattern, or a weighted average of parameter values ​​associated with the given film grain pattern.

[0181] A first film grain pattern of the reduced set of film grain patterns may be associated with a first set of film grain parameters. A second film grain pattern of the reduced set of film grain patterns may be associated with a second set of film grain parameters. The device may receive a supplemental enhancement information (SEI) message indicating a third set of film grain parameters. The device may determine a first difference between the first set of film grain parameters and the third set of film grain parameters and a second difference between the second set of film grain parameters and the third set of film grain parameters. On a condition that the first difference is less than the second difference, the device may select the first film grain pattern to apply to pixel components of the block. On a condition that the second difference is less than the first difference, the device may select the second film grain pattern to apply to pixel components of the block.

[0182] The device may determine a scaling factor associated with the selected film grain pattern. The device may apply the scaling factor to the selected film grain pattern. The film grain pattern priority information may indicate rules for prioritizing the multiple film grain patterns and / or a maximum number of film grain patterns that the reduced set of film grain patterns may include. The pixel components of the block may be pixel intensity components.

[0183] A method (e.g., for video decoding) may involve obtaining film grain pattern priority information associated with a plurality of film grain patterns for a block. The method may involve determining a reduced set of film grain patterns from the plurality of film grain patterns based on the film grain pattern priority information for performing a film grain pattern analysis. The method may involve performing a film grain pattern analysis on the reduced set of film grain patterns. The method may involve selecting a film grain pattern from the reduced set of film grain patterns for applying to pixel components of the block based on the film grain pattern analysis. The method may involve applying the selected film grain pattern to the pixel components of the block.

[0184] The method may involve receiving a supplemental extension information (SEI) message comprising a list of parameters. Determining the reduced set of film grain patterns based on the film grain pattern priority information may involve determining that the reduced set of film grain patterns comprises film grain patterns associated with a number of parameters that are listed first in the SEI message. Each film grain pattern of the plurality of film grain patterns may be associated with a corresponding weight. Determining the reduced set of film grain patterns based on the film grain pattern priority information may involve determining that the reduced set of film grain patterns comprises a number of film grain patterns of the plurality of film grain patterns that have a maximum corresponding weight.

[0185] The corresponding weight for a given film grain pattern may be based on at least one of: a sum of intensity interval sizes associated with the given film grain pattern, a number of pixels to which the given film grain pattern is applied, a scaling factor associated with the given film grain pattern, an intensity value associated with the given film grain pattern, or a weighted average of parameter values ​​associated with the given film grain pattern.

[0186] A first film grain pattern of the reduced set of film grain patterns may be associated with a first set of film grain parameters. A second film grain pattern of the reduced set of film grain patterns may be associated with a second set of film grain parameters. The method may involve receiving a supplemental enhancement information (SEI) message indicating a third set of film grain parameters. Performing a film grain pattern analysis on the reduced set of film grain patterns may involve determining a first difference between the first set of film grain parameters and the third set of film grain parameters, and a second difference between the second set of film grain parameters and the third set of film grain parameters.

[0187] Selecting a film grain pattern to apply to pixel components of the block based on the film grain pattern analysis may involve selecting a first film grain pattern to apply to the pixel components of the block on condition that the first difference is less than the second difference, and selecting a second film grain pattern to apply to the pixel components of the block on condition that the second difference is less than the first difference. The method may involve determining a scaling factor associated with the selected film grain pattern. The method may involve applying the scaling factor to the selected film grain pattern.

[0188] An exemplary device (e.g., a device for video encoding) may include a processor configured to perform one or more actions: The device may generate a set of film grain parameters associated with a video image. The device may obtain film grain pattern priority information. The device may generate a supplemental enhancement information (SEI) message associated with the video image. The SEI message may include a set of film grain parameters associated with the video image and the film grain pattern priority information. The device may encode the video image to generate an encoded video image. The device may send the SEI message and the encoded video image.

[0189] The film grain pattern priority information may indicate a reduced set of film grain parameters. The reduced set of film grain parameters may include a number of film grain parameters that are listed first in the SEI message. Each film grain parameter in the set of film grain parameters may be associated with a corresponding weight. The film grain pattern priority information may indicate a reduced set of film grain parameters. The reduced set of film grain parameters may include a number of film grain parameters that have a maximum corresponding weight.

[0190] An exemplary method (e.g., for video encoding) may involve generating a set of film grain parameters associated with a video image. The method may involve obtaining film grain pattern priority information. The method may involve generating a supplemental enhancement information (SEI) message associated with the video image. The SEI message may include a set of film grain parameters associated with the video image and the film grain pattern priority information. The method may involve encoding the video image to generate an encoded video image. The method may involve sending the SEI message and the encoded video image.

[0191] Although the features and elements are described above in certain combinations, one skilled in the art will understand that each feature or element may be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware embodied 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 disks (DVDs). A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. A device equipped with a processor, The aforementioned processor, Obtaining film grain pattern priority information associated with multiple film grain patterns for a block, Based on the film grain pattern priority information, a reduced set of film grain patterns for which film grain pattern analysis should be performed is determined from the plurality of film grain patterns. Performing the film grain pattern analysis on the reduced set of film grain patterns, Based on the film grain pattern analysis, a film grain pattern is selected from the reduced set of film grain patterns to be applied to the pixel components of the block. Applying the selected film grain pattern to the pixel components of the block, A device configured to perform the following actions.

2. The processor is further configured to receive a Supplemental Extended Information (SEI) message containing a list of parameters, The device according to claim 1, wherein the processor is configured to determine the reduced set of film grain patterns based on the film grain pattern priority information, wherein the processor is configured to determine that the reduced set of film grain patterns includes film grain patterns associated with several parameters listed first in the SEI message.

3. The device according to claim 1, wherein each of the plurality of film grain patterns is associated with a corresponding weight, and the processor is configured to determine the reduced set of film grain patterns based on the film grain pattern priority information, wherein the processor is configured to determine that the reduced set of film grain patterns includes some of the plurality of film grain patterns having the largest corresponding weight.

4. The corresponding weights of a given film grain pattern are: The sum of the intensity interval sizes associated with the given film grain pattern, The number of pixels to which the given film grain pattern is applied, The scaling coefficient associated with the given film grain pattern, The intensity value associated with the given film grain pattern, The weighted average of the parameter values ​​associated with the given film grain pattern, The device according to claim 3, based on at least one of the following.

5. The first film grain pattern of the reduced set of film grain patterns is associated with the first set of film grain parameters, The second film grain pattern of the reduced set of film grain patterns is associated with a second set of film grain parameters, The processor is further configured to receive a Supplemental Extended Information (SEI) message indicating a third set of film grain parameters, The device according to claim 1, wherein the processor is configured to perform the film grain pattern analysis on the reduced set of film grain patterns, the processor is configured to determine a first difference between the first set of film grain parameters and the third set of film grain parameters, and a second difference between the second set of film grain parameters and the third set of film grain parameters.

6. The processor is configured to select the film grain pattern to apply to the pixel components of the block based on the film grain pattern analysis, Selecting the first film grain pattern to apply to the pixel components of the block, provided that the first difference is less than the second difference, Selecting the second film grain pattern to apply to the pixel components of the block, provided that the second difference is less than the first difference, The device according to claim 5, which includes being configured to perform

7. The aforementioned processor, Determining the scaling coefficient associated with the selected film grain pattern, Applying the scaling coefficient to the selected film grain pattern, The device according to claim 1, further configured to perform the following:

8. The aforementioned film grain pattern priority information is Rules for prioritizing the aforementioned multiple film grain patterns, The maximum number of film grain patterns that the reduced set of film grain patterns may include, The device according to claim 1, which shows the above.

9. The device according to claim 1, wherein the pixel component of the block includes a pixel intensity component.

10. It is a method, Obtaining film grain pattern priority information associated with multiple film grain patterns for a block, Based on the film grain pattern priority information, a reduced set of film grain patterns for which film grain pattern analysis should be performed is determined from the plurality of film grain patterns. Performing the film grain pattern analysis on the reduced set of film grain patterns, Based on the film grain pattern analysis, a film grain pattern is selected from the reduced set of film grain patterns to be applied to the pixel components of the block. Applying the selected film grain pattern to the pixel components of the block, Methods that include...

11. The method further comprises receiving a supplemental extended information (SEI) message containing a list of parameters, The method according to claim 10, wherein determining the reduced set of film grain patterns based on the film grain pattern priority information includes determining that the reduced set of film grain patterns includes film grain patterns associated with several parameters listed first in the SEI message.

12. The method according to claim 10, wherein each of the film grain patterns among the plurality of film grain patterns is associated with a corresponding weight, and determining the reduced set of film grain patterns based on the film grain pattern priority information includes determining that the reduced set of film grain patterns includes several film grain patterns among the plurality of film grain patterns having the largest corresponding weight.

13. The corresponding weights of a given film grain pattern are: The sum of the intensity interval sizes associated with the given film grain pattern, The number of pixels to which the given film grain pattern is applied, The scaling coefficient associated with the given film grain pattern, The intensity value associated with the given film grain pattern, The weighted average of the parameter values ​​associated with the given film grain pattern, The method according to claim 12, based on at least one of the following.

14. The first film grain pattern of the reduced set of film grain patterns is associated with the first set of film grain parameters, The second film grain pattern of the reduced set of film grain patterns is associated with a second set of film grain parameters, The method further includes receiving a supplemental extended information (SEI) message indicating a third set of film grain parameters, The method according to claim 10, wherein performing the film grain pattern analysis on the reduced set of film grain patterns includes determining a first difference between the first set of film grain parameters and the third set of film grain parameters, and a second difference between the second set of film grain parameters and the third set of film grain parameters.

15. Based on the film grain pattern analysis, selecting the film grain pattern to apply to the pixel components of the block is, Selecting the first film grain pattern to apply to the pixel components of the block, provided that the first difference is less than the second difference, Selecting the second film grain pattern to apply to the pixel components of the block, provided that the second difference is less than the first difference, The method according to claim 14, including the method described in claim 14.

16. The method described above is Determining the scaling coefficient associated with the selected film grain pattern, Applying the scaling coefficient to the selected film grain pattern, The method according to claim 10, further comprising:

17. The aforementioned film grain pattern priority information is Rules for prioritizing the aforementioned multiple film grain patterns, The maximum number of film grain patterns that the reduced set of film grain patterns may include, The method according to claim 10, which demonstrates the present invention.

18. The method according to claim 10, wherein the pixel component of the block includes a pixel intensity component.

19. A video encoding device equipped with a processor, The aforementioned processor, To generate a set of film grain parameters associated with a video image, Determining film grain pattern priority information that shows a reduced set of film grain parameters, To generate a supplemental extended information (SEI) message associated with the video image, wherein the SEI message includes the set of film grain parameters associated with the video image and the film grain pattern priority information. The aforementioned video image is encoded to generate an encoded video image, To transmit the aforementioned SEI message and the encoded video image, A video encoding device configured to perform the following.

20. The video coding device according to claim 19, wherein each film grain parameter in the set of film grain parameters is associated with a corresponding weight, and the film grain pattern priority information indicates that the film grain parameter associated with the largest corresponding weight is listed first in the SEI message.

Images