# US 2025/0220183 A1 · Image decoding method and apparatus, and image coding method and apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0220183 A1 - Document ID: US20250220183A1 - Status: Published application - Kind: A1 - Application number: 18/998,260 - Filed: 2023-07-26 - Published: 2025-07-03 - Earliest claimed: 2022-07-26 - Assignees: Hangzhou Hikvision Digital Technology Co., Ltd. - Applicants: Hangzhou Hikvision Digital Technology Co., Ltd. - Inventors: Liang WEI; Fangdong CHEN; Li WANG; Xiaoyang WU - Web page: https://patentgrep.com/patent/US20250220183A1 ## CPC - H04N 19/124: Quantisation - G06V 10/751: {Comparing pixel values or logical combinations thereof, or feature values having positional relevance, e.g. template matching} - H04N 19/14: Coding unit complexity, e.g. amount of activity or edge presence estimation (H04N19/146 takes precedence) - H04N 19/154: Measured or subjectively estimated visual quality after decoding, e.g. measurement of distortion (use of rate-distortion criteria H04N19/147) - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/182: the unit being a pixel - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING ## Abstract A picture decoding method is provided, including: determining a predicted residual value of a pixel point according to a prediction manner of the pixel point, where the predicted residual value is configured to reflect a gradient of the pixel point, the prediction manner is configured to indicate a position of one or more reconstructed pixel points referenced when performing prediction on a pixel point, and the pixel point is any pixel point in a current coding block; determining a target quantization parameter (QP) value of a first pixel point according to the predicted residual value of the first pixel point, where the first pixel point is a target pixel point in the current coding block, and the target pixel point is a preset pixel point for adjusting the QP value; and performing dequantization on the first pixel point according to the target QP value of the first pixel point. ## Claims ### Claim 1 A picture decoding method, performed by a decoding device, comprising: determining a predicted residual value of a pixel point according to a prediction manner of the pixel point, wherein the predicted residual value is configured to reflect a gradient of the pixel point, the prediction manner is configured to indicate a position of one or more reconstructed pixel points referenced when performing prediction on a pixel point, and the pixel point is any pixel point in a current coding block; determining a target quantization parameter (QP) value of a first pixel point according to the predicted residual value of the first pixel point, wherein the first pixel point is a target pixel point in the current coding block, and the target pixel point is a preset pixel point for adjusting the QP value; and performing dequantization on the first pixel point according to the target QP value of the first pixel point. ### Claim 2 (depends on 1) The method according to claim 1, wherein the prediction manner comprises at least one of: performing prediction according to reconstructed pixel points on a left side and a right side of the pixel point; performing prediction according to one or more reconstructed pixel points on the left side of the pixel point; or performing prediction according to one or more reconstructed pixel points on an upper side of the pixel point. ### Claim 3 (depends on 2) The method according to claim 2, wherein the prediction manner of the pixel point is to perform prediction according to the reconstructed pixel points on the left side and the right side of the pixel point, and determining the predicted residual value of the pixel point according to the prediction manner of the pixel point comprises: calculating a difference between a pixel value of a second pixel point and a pixel value of a third pixel point as a first difference value, or taking a residual value of the second pixel point after performing dequantization as the first difference value, wherein the second pixel point is a first reconstructed pixel point on a left side of the pixel point, and the third pixel point is a first reconstructed pixel point on an upper side of the second pixel point; calculating a difference between a pixel value of a fourth pixel point and a pixel value of a fifth pixel point as a second difference value, or taking a residual value of the fourth pixel point after performing dequantization as the second difference value, wherein the fourth pixel point is a first reconstructed pixel point on a right side of the pixel point, and the fifth pixel point is a first reconstructed pixel point on an upper side of the fourth pixel point; and taking an average value of an absolute value of the first difference value and an absolute value of the second difference value as the predicted residual value of the pixel point. ### Claim 4 (depends on 2) The method according to claim 2, wherein the prediction manner of the pixel point is to perform prediction according to the one or more reconstructed pixel points on the left side of the pixel point, and determining the predicted residual value of the pixel point according to the prediction manner of the pixel point comprises: taking an absolute value of a difference between a pixel value of a tenth pixel point and a pixel value of an eleventh pixel point as the predicted residual value of the pixel point, wherein the tenth pixel point is a first reconstructed pixel point on a left side of the pixel point, and the eleventh pixel point is a first reconstructed pixel point on a left side of the tenth pixel point; or taking an absolute value of a difference between the pixel value of the tenth pixel point and a pixel value of a twelfth pixel point as the predicted residual value of the pixel point, wherein the twelfth pixel point is a first reconstructed pixel point on an upper side of the tenth pixel point; or taking an absolute value of a residual value of the tenth pixel point after performing dequantization as the predicted residual value of the pixel point. ### Claim 5 (depends on 2) The method according to claim 2, wherein the prediction manner of the pixel point is to perform prediction according to the one or more reconstructed pixel points on the upper side of the pixel point, and determining the predicted residual value of the pixel point according to the prediction manner of the pixel point comprises: taking an absolute value of a difference between a pixel value of a thirteenth pixel point and a pixel value of a fourteenth pixel point as the predicted residual value of the pixel point, wherein the thirteenth pixel point is a first reconstructed pixel point on an upper side of the pixel point, and the fourteenth pixel point is a first reconstructed pixel point on an upper side of the thirteenth pixel point; or taking an absolute value of a residual value of the thirteenth pixel point after performing dequantization as the predicted residual value of the pixel point. ### Claim 6 (depends on 1) The method according to claim 1, wherein the predicted residual value of the pixel point comprises: a target value or an average value of target values, wherein the target value is a gradient of one or more reconstructed pixel points surrounding the pixel point, or the target value is an absolute value of the gradient of the one or more reconstructed pixel points surrounding the pixel point, or the target value is a residual value of the one or more reconstructed pixel points surrounding the pixel point after performing dequantization, or the target value is an absolute value of the residual value of the one or more reconstructed pixel points surrounding the pixel point after performing dequantization. ### Claim 7 (depends on 1) The method according to claim 1, further comprising: determining a predicted QP value of the pixel point, wherein the predicted QP value of the pixel point is a QP value of the current coding block, wherein determining the target QP value of the first pixel point according to the predicted residual value of the first pixel point comprises: adjusting the predicted QP value of the first pixel point according to the predicted residual value of the first pixel point to obtain the target QP value of the first pixel point. ### Claim 8 (depends on 7) The method according to claim 7, wherein adjusting the predicted QP value of the first pixel point according to the predicted residual value of the first pixel point to obtain the target QP value of the first pixel point comprises: in response to the predicted QP value of the first pixel point being greater than or equal to a first threshold and less than or equal to a second threshold and the predicted residual value of the first pixel point being less than or equal to a third threshold, adjusting the predicted QP value of the first pixel point to obtain the target QP value, wherein the target QP value is less than the predicted QP value; and otherwise, taking the predicted QP value of the first pixel point as the target QP value of the first pixel point. ### Claim 9 (depends on 8) The method according to claim 8, wherein the first threshold is a QP value corresponding to just noticeable distortion, and the second threshold is an adjustable maximum QP value. ### Claim 10 (depends on 9) The method according to claim 9, wherein adjusting the predicted QP value of the first pixel point to obtain the target QP value of the first pixel point comprises: taking a larger value of a QP value obtained by subtracting a preset offset from the predicted QP value and the QP value corresponding to just noticeable distortion as the target QP value. ### Claim 11 (depends on 10) The method according to claim 10, wherein the QP value corresponding to just noticeable distortion is determined according to a bit depth of the first pixel point in a target channel or a channel index of the first pixel point; the adjustable maximum QP value is determined according to one or more of the bit depth of the first pixel point in the target channel, the channel index of the first pixel point and a filling degree of a bitstream buffer; the third threshold is determined according to one or more of the bit depth of the first pixel point in the target channel, the channel index of the first pixel point and a texture complexity of the current coding block; and the preset offset is determined according to one or more of the bit depth of the first pixel point in the target channel, the channel index of the first pixel point, the filling degree of the bitstream buffer and the texture complexity of the current coding block. ### Claim 12 A picture coding method, performed by a coding device, comprising: determining a predicted residual value of a pixel point according to a prediction manner of the pixel point, wherein the predicted residual value is configured to reflect a gradient of the pixel point, the prediction manner is configured to indicate a position of one or more reconstructed pixel points referenced when performing prediction on a pixel point, and the pixel point is any pixel point in a current coding block; determining a target quantization parameter (QP) value of a first pixel point according to the predicted residual value of the first pixel point, wherein the first pixel point is a target pixel point in the current coding block, and the target pixel point is a preset pixel point for adjusting the QP value; and performing quantization on the first pixel point according to the target QP value of the first pixel point. ### Claim 13 (depends on 12) The method according to claim 12, wherein the predicted residual value of the pixel point comprises: a target value or an average value of target values, wherein the target value is a gradient of one or more reconstructed pixel points surrounding the pixel point, or the target value is an absolute value of the gradient of the one or more reconstructed pixel points surrounding the pixel point, or the target value is a residual value of the one or more reconstructed pixel points surrounding the pixel point after performing dequantization, or the target value is an absolute value of the residual value of the one or more reconstructed pixel points surrounding the pixel point after performing dequantization. ### Claim 14 (depends on 12) The method according to claim 12, further comprising: determining a predicted QP value of the pixel point, wherein the predicted QP value of the pixel point is a QP value of the current coding block; wherein determining the target QP value of the first pixel point according to the predicted residual value of the first pixel point comprises: adjusting the predicted QP value of the first pixel point according to the predicted residual value of the first pixel point to obtain the target QP value of the first pixel point. ### Claim 15 (canceled) ### Claim 16 (canceled) ### Claim 17 (canceled) ### Claim 18 An electronic device, comprising a processor and a memory, wherein the memory is configured to store computer instructions, and the processor is configured to call and run the computer instructions from the memory to perform operations comprising: determining a predicted residual value of a pixel point according to a prediction manner of the pixel point, wherein the predicted residual value is configured to reflect a gradient of the pixel point, the prediction manner is configured to indicate a position of one or more reconstructed pixel points referenced when performing prediction on a pixel point, and the pixel point is any pixel point in a current coding block; determining a target quantization parameter (QP) value of a first pixel point according to the predicted residual value of the first pixel point, wherein the first pixel point is a target pixel point in the current coding block, and the target pixel point is a preset pixel point for adjusting the QP value; and performing dequantization on the first pixel point according to the target QP value of the first pixel point. ### Claim 19 (canceled) ### Claim 20 (depends on 12) An electronic device, comprising a processor and a memory, wherein the memory is configured to store computer instructions, and the processor is configured to call and run the computer instructions from the memory to perform the method according to claim 12. ### Claim 21 (depends on 1) A video coding system, comprising a coding device and a decoding device, wherein the coding device is communicatively connected to the decoding device, and the decoding device is configured to perform the method according to claim 1. ### Claim 22 (depends on 12) A video coding system, comprising a coding device and a decoding device, wherein the coding device is communicatively connected to the decoding device, and the coding device is configured to perform the method according to claim 12. ### Claim 23 (depends on 1) A non-transitory computer readable storage medium storing a computer program or instruction which, when executed by an electronic device, causes the electronic device to perform the method according to claim 1. ### Claim 24 (depends on 12) A non-transitory computer readable storage medium storing a computer program or instruction which, when executed by an electronic device, causes the electronic device to perform the method according to claim 12.