# US 10,873,760 B2 · Motion vector (MV) constraints and transformation constraints in video coding > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,873,760 B2 - Document ID: US10873760B2 - Status: Granted - Kind: B2 - Application number: 15/944,501 - Filed: 2018-04-03 - Published: 2018-10-11 - Granted: 2020-12-22 - Earliest claimed: 2017-04-07 - Assignees: Futurewei Technologies, Inc. - Applicants: Futurewei Technologies, Inc. - Inventors: Huanbang Chen; Haitao Yang; Jianle Chen - Web page: https://patentgrep.com/patent/US10873760B2 ## CPC - H04N 19/55: Motion estimation with spatial constraints, e.g. at image or region borders - 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 19/139: Analysis of motion vectors, e.g. their magnitude, direction, variance or reliability - H04N 19/176: the region being a block, e.g. a macroblock - H04N 19/433: characterised by techniques for memory access - H04N 19/52: by predictive encoding - H04N 19/521: {for estimating the reliability of the determined motion vectors or motion vector field, e.g. for smoothing the motion vector field or for correcting motion vectors} - H04N 19/523: with sub-pixel accuracy - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract An apparatus comprises: a memory; and a processor coupled to the memory and configured to: obtain candidate MVs corresponding to neighboring blocks that neighbor a current block in a video frame, generate a candidate list of the candidate MVs, select final MVs from the candidate list, and apply constraints to the final MVs or a transformation to obtain constrained MVs. An apparatus comprises: a memory; and a processor coupled to the memory and configured to: obtain candidate MVs corresponding to neighboring blocks that neighbor a current block in a video frame, generate a candidate list of the candidate MVs, apply constraints to the candidate MVs or a transformation to obtain constrained MVs, and select final MVs from the constrained MVs. ## Claims ### Claim 1 An apparatus comprising: a memory; and a processor coupled to the memory and configured to: obtain candidate motion vectors (MVs) corresponding to neighboring blocks that neighbor a current block in a video frame, generate a candidate list of the candidate MVs, select final MVs from the candidate list, and apply constraints to the final MVs or a transformation to obtain constrained MVs, wherein the constraints comprise an expression, wherein the expression comprises a threshold and at least one of a width of the current block or a height of the current block, wherein the threshold is an arbitrary number that is statically stored or dynamically signaled, wherein the constraints provide that a first square root of a first quantity is less than or equal to a second quantity, wherein the first quantity is based on a first final MV, a second final MV, a third final MV, a fourth final MV, and the width, and wherein the second quantity is based on the width and the threshold. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the constraints provide that a first absolute value of a first difference between a first final MV and a second final MV is less than or equal to a first quantity based on the width and the threshold, and wherein the constraints further provide that a second absolute value of a second difference between a third final MV and a fourth final MV is less than or equal to a second quantity based on the height and the threshold. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the constraints further provide that a second square root of a third quantity is less than or equal to a fourth quantity, wherein the third quantity is based on a fifth final MV, a sixth final MV, a seventh final MV, an eighth final MV, and the height, and wherein the fourth quantity is based on the height and the threshold. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the constraints provide that a first quantity is less than or equal to a second quantity, wherein the first quantity is based on a first width of a transformed block, a length of an interpolation filter, and a first height of the transformed block, and wherein the second quantity is based on the threshold, the width, and the height. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein the threshold is specific to uni-prediction or bi-prediction. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the constraints provide that a quantity is less than or equal to the threshold, wherein the quantity is directly proportional to a first memory bandwidth and a second memory bandwidth, and wherein the quantity is indirectly proportional to the width and the height. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the constraints provide that a first difference between a first width of a transformed block and the width is less than or equal to the threshold, and wherein the constraints further provide that a second difference between a first height of the transformed block and the height is less than or equal to the threshold. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the processor is further configured to: calculate a motion vector field (MVF) based on the constrained MVs; perform motion compensation prediction (MCP) based on the MVF to generate a prediction block for the current block; and encode an MV index. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein the processor is further configured to: decode an MV index; calculate a motion vector field (MVF) based on the constrained MVs; and perform motion compensation prediction (MCP) based on the MVF to generate a prediction block for the current block. ### Claim 10 A method comprising: obtaining candidate motion vectors (MVs) corresponding to neighboring blocks that neighbor a current block in a video frame; generating a candidate list of the candidate MVs; selecting final MVs from the candidate list; and applying constraints to the final MVs or a transformation to obtain constrained MVs, wherein the constraints comprise an expression, wherein the expression comprises a threshold and at least one of a width of the current block or a height of the current block, wherein the threshold is an arbitrary number that is statically stored or dynamically signaled, wherein the constraints provide that a quantity is less than or equal to the threshold, wherein the quantity is directly proportional to a first memory bandwidth and a second memory bandwidth, and wherein the quantity is indirectly proportional to the width and the height. ### Claim 11 An apparatus comprising: a memory; and a processor coupled to the memory and configured to: obtain candidate motion vectors (MVs) corresponding to neighboring blocks that neighbor a current block in a video frame, generate a candidate list of the candidate MVs, apply constraints to the candidate MVs or a transformation to obtain constrained MVs, wherein the constraints comprise an expression, wherein the expression comprises a threshold and at least one of a width of the current block or a height of the current block, wherein the threshold is an arbitrary number that is statically stored or dynamically signaled, wherein the constraints provide that a first square root of a first quantity is less than or equal to a second quantity, wherein the first quantity is based on a first final MV, a second final MV, a third final MV, a fourth final MV, and the width, and wherein the second quantity is based on the width and the threshold, and select final MVs from the constrained MVs. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the constraints provide that a first absolute value of a first difference between a first final MV and a second final MV is less than or equal to a first quantity based on the width and the threshold, and wherein the constraints further provide that a second absolute value of a second difference between a third final MV and a fourth final MV is less than or equal to a second quantity based on the height and the threshold. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the constraints further provide that a second square root of a third quantity is less than or equal to a fourth quantity, wherein the third quantity is based on a fifth final MV, a sixth final MV, a seventh final MV, an eighth final MV, and the height, and wherein the fourth quantity is based on the height and the threshold. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein the constraints provide that a first quantity is less than or equal to a second quantity, wherein the first quantity is based on a first width of a transformed block, a length of an interpolation filter, and a first height of the transformed block, and wherein the second quantity is based on the threshold, the width, and the height. ### Claim 15 (depends on 11) The apparatus of claim 11, wherein the constraints provide that a quantity is less than or equal to the threshold, wherein the quantity is directly proportional to a first memory bandwidth and a second memory bandwidth, and wherein the quantity is indirectly proportional to the width and the height. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein the constraints provide that a first difference between a first width of a transformed block and the width is less than or equal to the threshold, and wherein the constraints further provide that a second difference between a first height of the transformed block and the height is less than or equal to the threshold. ### Claim 17 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: calculate a motion vector field (MVF) based on the constrained MVs; perform motion compensation prediction (MCP) based on the MVF to generate a prediction block for the current block; and encode an MV index. ### Claim 18 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: decode an MV index; calculate a motion vector field (MVF) based on the constrained MVs; and perform motion compensation prediction (MCP) based on the MVF to generate a prediction block for the current block.