# US 12,764,314 B2 · DPB operation-based image or video coding > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,764,314 B2 - Document ID: US12764314B2 - Status: Granted - Kind: B2 - Application number: 18/009,610 - Filed: 2021-06-07 - Published: 2023-07-13 - Granted: 2026-10-13 - Earliest claimed: 2020-06-09 - Assignees: LG Electronics Inc. - Applicants: LG Electronics Inc. - Inventors: Seethal Paluri; Hendry Hendry; Seunghwan Kim - Web page: https://patentgrep.com/patent/US12764314B2 ## CPC - H04N 19/423: characterised by memory arrangements (H04N19/433 takes precedence) - H04N 19/172: the region being a picture, frame or field - H04N 19/70: characterised by syntax aspects related to video coding, e.g. related to compression standards - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract According to the disclosure of the present document, a decoded picture buffer (DPB) may be updated on the basis of DPB-related information. The DPB-related information may include a syntax element related to a maximum required size of the DPB. In updating the DPB, a bumping process may be invoked on the basis of a case where a first condition, in which the number of pictures in the DPB is neither greater than nor equal to a value obtained by adding 1 to a value of the syntax element related to the maximum required size of the DPB, is satisfied. ## Claims ### Claim 1 An image decoding method performed by a decoding apparatus, the method comprising: obtaining image information including decoded picture buffer (DPB) related information from a bitstream; updating a DPB based on the DPB related information; and decoding a current picture based on the DPB, wherein the DPB related information includes a syntax element related to a maximum required size of the DPB, and wherein based on (i) the current picture not being a first picture of a coded video sequence start (CVSS) access unit (AU) that is different from AU 0 and (ii) a first condition in which a number of pictures in the DPB is greater than or equal to a value of the syntax element related to the maximum required size of the DPB plus 1 being satisfied, a bumping process is invoked repeatedly only until the number of pictures in the DPB is less than the value of the syntax element related to the maximum required size of the DPB plus 1, and wherein the AU 0 is a first AU of the bitstream. ### Claim 2 (depends on 1) The image decoding method of claim 1, wherein the DPB related information includes a syntax element related to a maximum picture reorder number of the DPB or a syntax element related to maximum latency of the DPB, and wherein the invoking of the bumping process is not determined based on a second condition based on the syntax element related to the maximum picture reorder number of the DPB or a third condition based on the syntax element related to the maximum latency of the DPB. ### Claim 3 (depends on 2) The image decoding method of claim 2, wherein the bumping process is not invoked based on a case that the second condition or the third condition is satisfied, but the first condition is not satisfied. ### Claim 4 (depends on 2) The image decoding method of claim 2, wherein the second condition is a condition related to whether a number of pictures in the DPB marked as “needed for output” is greater than a value of the syntax element related to the maximum picture reorder number of the DPB, wherein the third condition is a condition related to whether a value of the syntax element related to the maximum latency of the DPB is not equal to 0, and whether there is at least one picture in the DPB marked as “needed for output” for which the associated variable PicLatencyCount is greater than or equal to MaxLatencyPictures, and wherein the MaxLatencyPictures is derived by (a value of the syntax element related to the maximum picture reorder number of the DPB+a value of the syntax element related to the maximum latency of the DPB−1). ### Claim 5 (depends on 1) The image decoding method of claim 1, wherein a DPB fullness is decreased by 1 for a picture storage buffer that is emptied in the DPB during the bumping process that is invoked based on the case that the first condition is satisfied. ### Claim 6 (depends on 1) The image decoding method of claim 1, after the bumping process invoked based on the case that the first condition is satisfied is performed, wherein an operation of decreasing a DPB fullness by 1 additionally for a picture storage buffer that is emptied in the DPB is not performed. ### Claim 7 An image encoding method, performed by an encoding apparatus, the method comprising: generating decoded picture buffer (DPB) related information; updating a DPB based on the DPB related information; and encoding image information including the DPB related information, wherein the DPB related information includes a syntax element related to a maximum required size of the DPB, and wherein based on (i) a current picture not being a first picture of a coded video sequence start (CVSS) access unit (AU) that is different from AU 0 and (ii) a first condition in which a number of pictures in the DPB is greater than or equal to a value of the syntax element related to the maximum required size of the DPB plus 1 being satisfied, a bumping process is invoked repeatedly only until the number of pictures in the DPB is less than the value of the syntax element related to the maximum required size of the DPB plus 1, and wherein the AU 0 is a first AU of the bitstream. ### Claim 8 (depends on 7) The image encoding method of claim 7, wherein the DPB related information includes a syntax element related to a maximum picture reorder number of the DPB or a syntax element related to maximum latency of the DPB, and wherein the invoking of the bumping process is not determined based on a second condition based on the syntax element related to the maximum picture reorder number of the DPB or a third condition based on the syntax element related to the maximum latency of the DPB. ### Claim 9 (depends on 8) The image encoding method of claim 8, wherein the bumping process is not invoked based on a case that the second condition or the third condition is satisfied, but the first condition is not satisfied. ### Claim 10 (depends on 8) The image encoding method of claim 8, wherein the second condition is a condition related to whether a number of pictures in the DPB marked as “needed for output” is greater than a value of the syntax element related to the maximum picture reorder number of the DPB, wherein the third condition is a condition related to whether a value of the syntax element related to the maximum latency of the DPB is not equal to 0, and whether there is at least one picture in the DPB marked as “needed for output” for which the associated variable PicLatencyCount is greater than or equal to MaxLatencyPictures, and wherein the MaxLatencyPictures is derived by (a value of the syntax element related to the maximum picture reorder number of the DPB+a value of the syntax element related to the maximum latency of the DPB−1). ### Claim 11 (depends on 7) The image encoding method of claim 7, wherein a DPB fullness is decreased by 1 for a picture storage buffer that is emptied in the DPB during the bumping process that is invoked based on the case that the first condition is satisfied. ### Claim 12 (depends on 7) The image encoding method of claim 7, after the bumping process invoked based on the case that the first condition is satisfied is performed, wherein an operation of decreasing a DPB fullness by 1 additionally for a picture storage buffer that is emptied in the DPB is not performed. ### Claim 13 (depends on 7) A non-transitory computer-readable storage medium for storing a bitstream generated by the image encoding method of claim 7. ### Claim 14 A method for transmitting data for image information comprising: generating decoded picture buffer (DPB) related information; updating a DPB based on the DPB related information; and encoding the image information including the DPB related information, wherein the DPB related information includes a syntax element related to a maximum required size of the DPB, and wherein based on (i) a current picture not being a first picture of a coded video sequence start (CVSS) access unit (AU) that is different from AU 0 and (ii) a first condition in which a number of pictures in the DPB is greater than or equal to a value of the syntax element related to the maximum required size of the DPB plus 1 being satisfied, a bumping process is invoked repeatedly only until the number of pictures in the DPB is less than the value of the syntax element related to the maximum required size of the DPB plus 1, and wherein the AU 0 is a first AU of the bitstream.