Abstract: An encoder, when sub-block encoding is to be performed, determines a plurality of sub-blocks in a first image block, the plurality of sub-blocks including a first sub-block, determines a first motion vector for the first sub-block by referring to a first candidate list, performs first inter prediction processing on the first sub-block using the first motion vector, and encodes the first image block using a result of the first inter prediction processing. When partition encoding is to be performed, the encoder, in operation, determines a plurality of partitions in a second image block, the plurality of partitions including a first partition, determines a second motion vector for the first partition by referring to a second candidate list, performs second inter prediction processing on the first partition using the second motion vector, and encodes the second image block using a result of the second inter prediction processing.

Abstract: An encoder includes circuitry and a memory coupled to the circuitry. The circuitry, in operation, determines whether or not a ternary split process of splitting a block into three sub blocks in a first direction parallel to a first longer side of the block is allowed by comparing a size of a second shorter side of the block to a minimum threshold value. The circuitry, responsive to the ternary split process being allowed, writes, into a bitstream, a split direction parameter indicative of a splitting direction. The circuitry, in operation, splits the block into a plurality of sub blocks in a direction indicated by the split direction parameter; and encodes the plurality of sub blocks. The minimum threshold value corresponds to a minimum size supported in a transform process.

Abstract: An encoder determines, based on a width and a height of a block, whether or not to disable a prediction mode in which the block is split along a partitioning line defined by a distance and an angle and then prediction is performed; and encodes the block with the prediction mode disabled or not disabled according to a result of the determination on whether or not to disable the prediction mode. Here, the distance is the shortest distance between the center of the block and the partitioning line, and the angle is an angle representing a direction from the center of the block toward the partitioning line in the shortest distance. The encoder determines to disable the prediction mode when (i) a width-to-height ratio is at least 8 or (ii) a height-to-width ratio is at least 8.

Abstract: An encoder that encodes a video includes a processor and memory. Using the memory, the processor: derives a prediction error of an image included in the video, by subtracting a prediction image of the image from the image; determines a secondary transform basis based on a primary transform basis, the primary transform basis being a transform basis for a primary transform to be performed on the prediction error, the secondary transform basis being a transform basis for a secondary transform to be performed on a result of the primary transform; performs the primary transform on the prediction error using the primary transform basis; performs the secondary transform on a result of the primary transform using the secondary transform basis; performs quantization on a result of the secondary transform; and encodes a result of the quantization as data of the image.

Abstract: An image decoder includes circuitry and a memory, wherein the circuitry, in operation, calculates first values of a first partition in a current block, using a first motion vector for the first partition; calculates second values of a second partition in the current block, using a second motion vector for the second partition; calculates third values of a set of pixels between the first partition and the second partition, using the first motion vector; calculates fourth values of the set of pixels, using the second motion vector; and weights the third values and the fourth values. A number of pixels in a row in the set of pixels is two or more, and two or more weights applied to the third values increase along the row.

Abstract: An image encoder/decoder includes circuitry and a memory coupled to the circuitry. When a geometry of a block of a picture satisfies a first condition, the circuitry splits the block of the picture into sub blocks having a first set of geometries. When the geometry of the block does not satisfy the first condition, the circuitry splits the block of the picture into sub blocks having a second set of geometries, the second set of geometries being different from the first set of geometries. The circuitry encodes/decodes the sub blocks of the block.

Abstract: An encoder includes circuitry and memory coupled to the circuitry. The circuitry, in operation: determines whether a size of a current block, which is a unit for which a vector candidate list including vector candidates is generated, is less than or equal to a threshold; when the size of the current block is less than or equal to the threshold, generates the vector candidate list by registering a history-based motion vector predictor (HMVP) vector candidate in the vector candidate list from an HMVP table without performing a first pruning process; when the size of the current block is greater than the threshold, generates the vector candidate list by performing the first pruning process and registering the HMVP vector candidate in the vector candidate list from the HMVP table; and encodes the current block using the vector candidate list.

Abstract: An encoder encodes a video, and includes: circuitry; and memory coupled to the circuitry. Using the memory, the circuitry: obtains at least two items of prediction information for a first partition included in the video; derives at least one template from neighboring samples which neighbor the first partition; calculates at least two costs, using the at least one template and the at least two items of prediction information; using the at least two costs, (i) determines at least one splitting direction for the first partition or (ii) assigns one of the at least two items of prediction information to a second partition split from the first partition according to the splitting direction, and another thereof to a third partition split from the first partition according to the splitting direction; and encodes the first partition according to the splitting direction and the at least two items of prediction information.

Abstract: A transmission method in the present disclosure includes; obtaining an image and image signal characteristics information indicating one of an opto-electrical transfer function (OETF) or an electro-optical transfer function (EOTF) as image signal characteristics of the image; and transmitting a signal including the image and the image signal characteristics information. According to the transmission method in the present disclosure, a receiving device that received a high dynamic range (HDR) image and a standard dynamic range (SDR) image transmitted through broadcasting or the like can display these images appropriately.

Abstract: A decoder comprises circuitry and memory. The circuitry, using the memory, in operation, determines a number of first pixels and a number of second pixels used in a deblocking filter process, wherein the first pixels are located at an upper side of a block boundary and the second pixels are located at a lower side of the block boundary, and performs the deblocking filter process on the block boundary. The number of the first pixels and the number of the second pixels are selected from among candidates, wherein the candidates include at least 4 and M larger than 4. Response to a location of the block boundary being a predetermined location, the number of the first pixels used in the deblocking filter process is limited to be 4.

Abstract: A method includes causing a computer of a communication terminal to perform a process including acquiring, in response to receipt of a beacon signal from a vending machine, identification information and type information and stock information of drinks from the vending machine by short-range wireless communication; acquiring preference information on drinks of a user of the communication terminal; acquiring current biological information of the user; generating, based on the identification information, the type information, the stock information, the preference information, and the biological information, a push notification screen that recommends at least one drink matching a preference of the user indicated by the preference information in relation to a current physical condition of the user indicated by the biological information from among the drinks stored in the vending machine indicated by the identification information; and displaying the push notification screen on a display of the communication term

Abstract: An encoder which encodes a video including a plurality of pictures includes circuitry and memory. Using the memory, the circuitry performs: encoding a first picture among the plurality of pictures; and performing (i) a first operation for encoding a parameter set for a second picture which follows the first picture in coding order among the plurality of pictures after encoding the first picture, and encoding the second picture after encoding the parameter set, or (ii) a second operation for encoding the second picture without encoding the parameter set after encoding the first picture. The circuitry performs the first operation when the second picture is a determined picture, in the performing of the first operation or the second operation.

Abstract: An encoder that includes memory and circuitry coupled to the memory. The circuitry encodes a slice into one or more data access regions in a variable length encoding process. The circuitry encodes one or more offsets into a slice header, based on a flag written into a sequence header and a total number of the one or more data access regions. The one or more offsets each specify a head position of a corresponding one of the one or more data access regions in a bitstream. When the flag indicates that the one or more offsets are to be encoded and the total number is at least two, the one or more offsets are encoded. The flag switches between encoding and not encoding the one or more offsets regardless of whether the total number is at least two.

Abstract: An encoder includes memory and circuitry coupled to the memory. The circuitry, for each of temporal sub-layers for temporal scalability different from spatial scalability, stores first parameters into buffering period supplemental enhancement information (SEI) and encodes the first parameters. The first parameters present initial delays in timing to extract data from a coded picture buffer (CPB). The circuitry stores a second parameter into the buffering period SEI and encodes the second parameter. The second parameter indicates a total number of the temporal sub-layers. A value of the second parameter is equal to a value of a third parameter that is encoded into a sequence parameter set and indicates a total number of the temporal sub-layers.

Abstract: An encoder includes circuitry, and memory coupled to the circuitry. The circuitry, in operation, for each of a plurality of sub-bitstreams having mutually different frame rates, encodes identification information into a header of a bitstream including the plurality of sub-bitstreams, the identification information indicating a temporal ID that is an identifier of a temporal layer related to a temporal scalability and corresponds to the sub-bitstream, and encodes level information indicating a conformance level of the sub-bitstream.

Abstract: An encoder includes circuitry and memory connected to the circuitry. In operation, the circuitry: corrects a base motion vector using a correction value for correcting the base motion vector in a predetermined direction; and encodes a current partition to be encoded in an image of a video, using the base motion vector corrected. The correction value is specified by a first parameter and a second parameter, the first parameter indicating a table to be selected from among a plurality of tables each including values, the second parameter indicating one of the values included in the table to be selected indicated by the first parameter. In each of the plurality of tables, a smaller value among the values is assigned a smaller index. Each of the plurality of tables includes a different minimum value among the values.

Abstract: An image encoder writes a first parameter and a second parameter to a bitstream, and derives a partition mode based on the first and second parameters. Responsive to the derived partition mode being a first partition mode, the image encoder executes the first partition mode including: splitting a block of a picture into a plurality of first blocks including a N×2N block sized N pixels by 2N pixels; splitting the N×2N block, wherein a ternary split is allowed to split the N×2N block in a vertical direction, which is a direction along the 2N pixels, into a plurality of sub blocks including at least one sub block sized N/4×2N, while a binary split is not allowed to split the N×2N block in the vertical direction into two sub blocks that are equally sized N/2×2N; and encoding the plurality of sub blocks.

Abstract: An encoder includes circuitry and memory. Using the memory, the circuitry performs prediction on an image. A motion vector predictor list used in the prediction includes a spatially neighboring motion vector predictor obtained from a block spatially neighboring a current block, and a spatially broad motion vector predictor obtained from a block positioned at any of a plurality of predetermined positions in a second range that is broader than a first range that spatially neighbors the current block. The plurality of predetermined positions are defined by a regular interval using the top-left of a current picture as a reference point.

Abstract: An encoder includes processing circuitry and a memory coupled to the processing circuitry. Using the memory, the processing circuitry is configured to: change values of pixels in a first block and a second block to filter a boundary between the first block and the second block. The pixels include type one pixels and type two pixels different from the type one pixels. The first set of filter coefficients applied to the type one pixels in the first block and the second set of filter coefficients applied to the type one pixels in the second block are selected to be asymmetrical with respect to the boundary.

Abstract: An encoder which includes circuitry and memory. Using the memory, the circuitry generates a list which includes candidates for a first motion vector for a first partition. The list has a maximum list size and an order of the candidates, and at least one of the maximum list size or the order of the candidates is dependent on at least one of a partition size or a partition shape of the first partition. The circuitry selects the first motion vector from the candidates included in the list; encodes an index indicating the first motion vector among the candidates in the list into the bitstream based on the maximum list size; and generates the predicted image for the first partition using the first motion vector.