US 12,219,170 B2
Methods for deriving a motion vector prediction in video coding
Kiran Mukesh Misra, Vancouver, WA (US); Frank Bossen, Vancouver, WA (US); and Christopher Andrew Segall, Vancouver, WA (US)
Assigned to SHARP KABUSHIKI KAISHA, Sakai (JP)
Filed by Sharp Kabushiki Kaisha, Sakai (JP)
Filed on Mar. 19, 2024, as Appl. No. 18/608,966.
Application 18/608,966 is a continuation of application No. 18/141,134, filed on Apr. 28, 2023, granted, now 11,979,599.
Application 18/141,134 is a continuation of application No. 17/745,020, filed on May 16, 2022, granted, now 11,677,974, issued on Jun. 13, 2023.
Application 17/745,020 is a continuation of application No. 17/293,158, granted, now 11,375,230, issued on Jun. 28, 2022, previously published as PCT/JP2019/044730, filed on Nov. 14, 2019.
Claims priority of provisional application 62/815,109, filed on Mar. 7, 2019.
Claims priority of provisional application 62/793,080, filed on Jan. 16, 2019.
Claims priority of provisional application 62/793,311, filed on Jan. 16, 2019.
Claims priority of provisional application 62/792,872, filed on Jan. 15, 2019.
Claims priority of provisional application 62/787,695, filed on Jan. 2, 2019.
Claims priority of provisional application 62/768,772, filed on Nov. 16, 2018.
Prior Publication US 2024/0244251 A1, Jul. 18, 2024
Int. Cl. H04N 19/52 (2014.01); H04N 19/176 (2014.01)
CPC H04N 19/52 (2014.11) [H04N 19/176 (2014.11)] 1 Claim
OG exemplary drawing
 
1. A method of performing motion vector prediction for coding video data, the method comprising:
inputting a motion vector for a current block (currCb) in a current picture (currPic);
deriving a first value based on a second value derived by right shifting the motion vector by a first shift value;
deriving a maskinformation based on the first value, a right shift operation and a left shift operation;
deriving a rounding information based on the first value, a right shift operation and a left shift operation;
deriving a modified motion vector by masking a sum of the rounding information and the motion vector with the mask information; and
deriving a collocated motion vector variable, for a temporal motion vector, based on the modified motion vector in a case that LongTermRefPic (currPic, currCb, refIdxLX, LX) is equal to LongTermRefPic (ColPic, colCb, refIdxCol, listCol),
wherein
refIdxLX is an index from reference picture list (LX) of a slice of the current picture,
ColPic is a collocated picture used for temporal motion vector prediction for the current picture,
colCb is a collocated block, inside ColPic, for the current block,
refIdxCol is an index from reference picture list (listCol) of a slice of the ColPic, and
Long TermRefPic (currPic, currCb, refIdxLX, LX) equals to 1 specifies that a picture with refIdxLX is marked as “used for long term reference”.