Methods of constrained intra block copy for reducing worst case bandwidth in video coding

Abstract

A method and apparatus of video coding using IntraBC (Intra Block Copy) for video data are disclosed. Restricted prediction is determined, in which one or more selected PU (prediction unit) sizes, PU prediction types or both are disabled or disallowed. Video coding is applied to the current block using coding modes including IntraBC prediction in accordance with the restricted prediction. The selected PU sizes, PU prediction types or both may correspond to 8×8 bi-prediction PU. In one example, the selected PU sizes, PU prediction types or both are disabled or disallowed for the restricted prediction except one or more conditions are determined to be satisfied. The conditions may correspond to at least one of two motion vectors of the 8×8 bi-prediction PU having integer values, the conditions may also correspond to at least one of motion vector components of the 8×8 bi-prediction PU having integer valueIntraBCIntraBCIntraBCIntraBCIntraBC.

Dependencies are inferred from the claim text.