Offset temporal motion vector predictor (TMVP)

A method of temporal motion vector prediction for inter block coding in High Efficiency Video Coding (HEVC) that relies on a block based translational model, the method comprising:

• designating a current prediction block as an area for motion compensation using HEVC where all the pixels inside the current prediction block perform identical translation temporally using either one or more motion vectors MVs;
• deriving a coordinate offset for the current prediction block from the MVs of its spatially neighboring blocks;
• defining an offset of a temporal motion vector predictor (TMVP) for the current prediction block as the MV of an offset block which is in the geometrical location of the current prediction block coordinate plus the coordinate offset in a specified temporal reference picture;
• and
• using the offset TMVP to code MVs,
• wherein the motion vectors of neighboring prediction blocks to the current prediction block are used to calculate the offset for the TMVP,
• wherein the neighboring prediction blocks located in a first three positions in a merge candidate list for the current prediction block are used in calculating the offset for the TMVP, wherein the three neighboring prediction blocks comprise a left (L), an above (A), and an above-left (AL),
• wherein with the three neighboring prediction blocks, the offset for the TMVP for the current prediction block is derived as median of motion vectors of these neighbors, as follows:
• dx=median (Lx, ALx, Ax)
• dy=median (Ly, ALy, Ay)
• wherein Lx, ALx, Ax are the x component of motion vectors of Left neighbor, Above-left neighbor, and Above neighbor, respectively, and
• wherein Ly, ALy, Ay are the y component of Left neighbor, Above-left neighbor, and Above neighbor, respectively.