Method and apparatus for encoding or decoding video data with sub-pixel motion vector refinement

A method for encoding video data comprising frames, each frame being split into blocks of pixels, the method comprising for a block of pixels:

• determining a motion vector to be refined;
• refining the determined motion vector, by evaluating motion vectors at sub-pixel positions in the neighbourhood of the determined motion vector;
• and
• encoding the block of pixels using the refined motion vector,
• wherein the sub-pixel positions are evaluated according to a pattern selected from a plurality of patterns for refining the determined motion vector;
• wherein the plurality of patterns includes a horizontal pattern and a vertical pattern which are based on a first pixel position indicated by the determined motion vector,
• wherein, when using the horizontal pattern, a plurality of sub-pixel positions on the right of the first pixel position and a plurality of sub-pixel positions on the left of the first pixel position are evaluated, and
• wherein, when using the vertical pattern, a plurality of sub-pixel positions above the first pixel position and a plurality of sub-pixel positions below the first pixel position are evaluated.

A method for decoding video data comprising frames, each frame being split into blocks of pixels, the method comprising for a block of pixels:

• determining a motion vector to be refined;
• refining the determined motion vector, by evaluating motion vectors at sub-pixel positions in the neighbourhood of the determined motion vector;
• and
• decoding the block of pixels using the refined motion vector,
• wherein the sub-pixel positions are evaluated according to a pattern selected from a plurality of patterns for refining the determined motion vector;
• wherein the plurality of patterns includes a horizontal pattern and a vertical pattern which are based on a first pixel position indicated by the determined motion vector,
• wherein, when using the horizontal pattern, a plurality of sub-pixel positions on the right of the first pixel position and a plurality of sub-pixel positions on the left of the first pixel position are evaluated, and
• wherein, when using the vertical pattern, a plurality of sub-pixel positions above the first pixel position and a plurality of sub-pixel positions below the first pixel position are evaluated.

An apparatus for encoding video data comprising frames, each frame being split into blocks of pixels, the apparatus comprising one or more processors configured to encode a block of pixels by:

• determining a motion vector to be refined;
• refining the determined motion vector, by evaluating motion vectors at sub-pixel positions in the neighbourhood of the determined motion vector;
• and
• encoding the block of pixels using the refined motion vector,
• wherein the sub-pixel positions are evaluated according to a pattern selected from a plurality of patterns for refining the determined motion vector,
• wherein the plurality of patterns includes a horizontal pattern and a vertical pattern which are based on a first pixel position indicated by the determined motion vector,
• wherein, when using the horizontal pattern, a plurality of sub-pixel positions on the right of the first pixel position and a plurality of sub-pixel positions on the left of the first pixel position are evaluated, and
• wherein, when using the vertical pattern, a plurality of sub-pixel positions above the first pixel position and a plurality of sub-pixel positions below the first pixel position are evaluated.

An apparatus for decoding video data comprising frames, each frame being split into blocks of pixels, the apparatus comprising one or more processors configured to decode a block of pixels by:

• determining a motion vector to be refined;
• refining the determined motion vector, by evaluating motion vectors at sub-pixel positions in the neighbourhood of the determined motion vector;
• and
• decoding the block of pixels using the refined motion vector,
• wherein the sub-pixel positions are evaluated according to a pattern selected from a plurality of patterns for refining the determined motion vector,
• wherein the plurality of patterns includes a horizontal pattern and a vertical pattern which are based on a first pixel position indicated by the determined motion vector,
• wherein, when using the horizontal pattern, a plurality of sub-pixel positions on the right of the first pixel position and a plurality of sub-pixel positions on the left of the first pixel position are evaluated, and
• wherein, when using the vertical pattern, a plurality of sub-pixel positions above the first pixel position and a plurality of sub-pixel positions below the first pixel position are evaluated.