Method and apparatus for block vector prediction with integer offsets in intra picture block compensation

A video decoder for video decoding, comprising:

• processing circuitry configured to:
• receive a coded video bitstream containing a current picture,
• determine whether a current block in the current picture is coded in intra block copy (IBC) mode,
• in response to a determination that the current block is coded in the IBC mode, determine whether a mode with a motion vector offset is enabled for the IBC encoded current block, and
• in response to a determination that the mode with the motion vector offset is enabled for the IBC encoded current block, decode the current block in accordance with an offset associated with the current block,
• wherein fractional offsets are not permitted for the IBC encoded current block irrespective of whether a first flag that indicates whether fractional offsets are permitted for the mode with the motion vector offset (i) is signaled in the coded video bitstream and (ii) is a value permitting fractional offsets, and
• wherein, in response to a determination that the motion vector offset is a fractional offset, the motion vector offset is left shifted such that the motion vector offset is converted from the fractional offset to an integer offset.

A non-transitory computer readable medium having instructions stored therein, which when executed by a processor in method of video decoding performed by a video decoder, the method comprising:

• receiving a coded video bitstream containing a current picture;
• determining whether a current block in the current picture is coded in intra block copy (IBC) mode;
• in response to a determination that the current block is coded in the IBC mode, determining whether a mode with a motion vector offset is enabled for the IBC encoded current block;
• and
• in response to a determination that the mode with the motion vector offset is enabled for the IBC encoded current block, decoding the current block in accordance with an offset associated with the current block,
• wherein fractional offsets are not permitted for the IBC encoded current block irrespective of whether a first flag that indicates whether fractional offsets are permitted for the mode with the motion vector offset (i) is signaled in the coded video bitstream and (ii) is a value permitting fractional offsets, and
• wherein, in response to a determination that the motion vector offset is a fractional offset, the motion vector offset is left shifted such that the motion vector offset is converted from the fractional offset to an integer offset.