# US 12,764,338 B2 · Reference picture resampling > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,764,338 B2 - Document ID: US12764338B2 - Status: Granted - Kind: B2 - Application number: 18/747,861 - Filed: 2024-06-19 - Published: 2024-10-10 - Granted: 2026-10-13 - Earliest claimed: 2020-06-04 - Assignees: Beijing Bytedance Network Technology Co., Ltd.; Bytedance Inc. - Applicants: Beijing Bytedance Network Technology Co., Ltd.; Bytedance Inc. - Inventors: Zhipin Deng; Li Zhang; Ye-Kui Wang; Kai Zhang - Web page: https://patentgrep.com/patent/US12764338B2 ## CPC - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N 19/105: Selection of the reference unit for prediction within a chosen coding or prediction mode, e.g. adaptive choice of position and number of pixels used for prediction - H04N 19/174: the region being a slice, e.g. a line of blocks or a group of blocks - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract Examples of video encoding methods and apparatus and video decoding methods and apparatus are described. An example method of video processing includes performing a conversion between a current picture of a video and a bitstream of the video according to a rule. The rule specifies that a number of entries in a reference picture list of the current picture is greater than 0 in response to (1) one or more slices in the current picture being allowed to have a slice type other than an Intra (I) slice type, and (2) reference picture list (RPL) information being present in a picture header. ## Claims ### Claim 1 A method of processing video data, comprising: performing a conversion between a current picture of a video and a bitstream of the video according to a rule, wherein the rule includes a bitstream constraint which specifies that a number of entries in a reference picture list of the current picture is greater than 0 in response to (1) one or more slices in the current picture being allowed to have a slice type other than an Intra (I) slice type, and (2) reference picture list (RPL) information being present in a picture header, and wherein the rule further specifies that a range of a value of a first syntax element specifying a number of points in a quantization parameter (QP) table associated with a conversion of a current video block of the current picture is based on a value of a second syntax element specifying a starting luma and chroma QP used to describe the QP table, wherein the QP table is an i-th chroma QP mapping table. ### Claim 2 (depends on 1) The method of claim 1, wherein the reference picture list is a reference picture list 0. ### Claim 3 (depends on 1) The method of claim 1, wherein a first syntax flag in the picture header indicates whether the one or more slices in the current picture are allowed to have the slice type other than the Intra (I) slice type. ### Claim 4 (depends on 1) The method of claim 1, wherein a second syntax flag in a picture parameter set indicates whether the RPL information is present in the picture header instead of slice headers. ### Claim 5 (depends on 1) The method of claim 1, wherein the number of entries in the reference picture list of the current picture is indicated by a third syntax element included in the bitstream. ### Claim 6 (depends on 1) The method of claim 1, wherein the conversion comprises encoding the video into the bitstream. ### Claim 7 (depends on 1) The method of claim 1, wherein the conversion comprises decoding the video from the bitstream. ### Claim 8 An apparatus for processing video data comprising a processor and a non-transitory memory with instructions thereon, wherein the instructions upon execution by the processor, cause the processor to: perform a conversion between a current picture of a video and a bitstream of the video according to a rule, wherein the rule includes a bitstream constraint which specifies that a number of entries in a reference picture list of the current picture is greater than 0 in response to (1) one or more slices in the current picture being allowed to have a slice type other than an Intra (I) slice type, and (2) reference picture list (RPL) information being present in a picture header, and wherein the rule further specifies that a range of a value of a first syntax element specifying a number of points in a quantization parameter (QP) table associated with a conversion of a current video block of the current picture is based on a value of a second syntax element specifying a starting luma and chroma QP used to describe the QP table, wherein the QP table is an i-th chroma QP mapping table. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the reference picture list is a reference picture list 0. ### Claim 10 (depends on 8) The apparatus of claim 8, wherein a first syntax flag in the picture header indicates whether the one or more slices in the current picture are allowed to have the slice type other than the Intra (I) slice type. ### Claim 11 (depends on 8) The apparatus of claim 8, wherein a second syntax flag in a picture parameter set indicates whether the RPL information is present in the picture header instead of slice headers. ### Claim 12 (depends on 8) The apparatus of claim 8, wherein the number of entries in the reference picture list of the current picture is indicated by a third syntax element included in the bitstream. ### Claim 13 A non-transitory computer-readable storage medium storing instructions that cause a processor to: perform a conversion between a current picture of a video and a bitstream of the video according to a rule, wherein the rule includes a bitstream constraint which specifies that a number of entries in a reference picture list of the current picture is greater than 0 in response to (1) one or more slices in the current picture being allowed to have a slice type other than an Intra (I) slice type, and (2) reference picture list (RPL) information being present in a picture header, and wherein the rule further specifies that a range of a value of a first syntax element specifying a number of points in a quantization parameter (QP) table associated with a conversion of a current video block of the current picture is based on a value of a second syntax element specifying a starting luma and chroma QP used to describe the QP table, wherein the QP table is an i-th chroma QP mapping table. ### Claim 14 (depends on 13) The non-transitory computer-readable storage medium of claim 13, wherein the reference picture list is a reference picture list 0. ### Claim 15 (depends on 13) The non-transitory computer-readable storage medium of claim 13, wherein a first syntax flag in the picture header indicates whether the one or more slices in the current picture are allowed to have the slice type other than the Intra (I) slice type, and a second syntax flag in a picture parameter set indicates whether the RPL information is present in the picture header instead of slice headers. ### Claim 16 (depends on 13) The non-transitory computer-readable storage medium of claim 13, wherein the number of entries in the reference picture list of the current picture is indicated by a third syntax element included in the bitstream. ### Claim 17 A method for storing a bitstream of a video, comprising: generating the bitstream of the video from a current picture in the video according to a rule; and storing the bitstream in a non-transitory computer-readable recording medium, wherein the rule includes a bitstream constraint which specifies that a number of entries in a reference picture list of the current picture is greater than 0 in response to (1) one or more slices in the current picture being allowed to have a slice type other than an Intra (I) slice type, and (2) reference picture list (RPL) information being present in a picture header, and wherein the rule further specifies that a range of a value of a first syntax element specifying a number of points in a quantization parameter (QP) table associated with a conversion of a current video block of the current picture is based on a value of a second syntax element specifying a starting luma and chroma QP used to describe the QP table, wherein the QP table is an i-th chroma QP mapping table. ### Claim 18 (depends on 17) The method of claim 17, wherein the reference picture list is a reference picture list 0. ### Claim 19 (depends on 17) The method of claim 17, wherein a first syntax flag in the picture header indicates whether the one or more slices in the current picture are allowed to have the slice type other than the Intra (I) slice type, and a second syntax flag in a picture parameter set indicates whether the RPL information is present in the picture header instead of slice headers. ### Claim 20 (depends on 17) The method of claim 17, wherein the number of entries in the reference picture list of the current picture is indicated by a third syntax element included in the bitstream.