Method of Video Coding Using Prediction based on Intra Picture Block Copy

Abstract

A method of signaling of coding modes including an IntraBC mode (Intra-block copy mode) to improve the coding efficiency is disclosed. The embodiment takes into consideration the facts that Inter prediction is more common in Inter slices than IntraBC prediction. In another embodiment, a binary sub-tree is disclosed that includes all the partition modes associated with IntraBC mode and the binary sub-tree consists of only said all members of the partition mode group.

1 . A method of signaling of coding mode including an IntraBC mode (Intra-block copy mode) for a picture, wherein the picture is divided into multiple coding units (CU), the method comprising:
 receiving input data associated with a current coding unit in a current picture, wherein the current coding unit is coded using a prediction mode selected from a prediction mode group comprising a Skip mode, an Inter mode, the IntraBC mode and an Intra mode;   if the Skip mode is selected for the current coding unit:   encoding or decoding the Skip mode using a first binary codeword with 1 bit; and   encoding or decoding the current coding unit without any residue information and motion information;   if the Inter mode is selected for the current coding unit:   encoding or decoding the Inter mode using a second binary codeword with 2 bits; and   encoding or decoding the current coding unit using temporal prediction;   if the IntraBC mode is selected for the current coding unit:   encoding or decoding the IntraBC mode using a third binary codeword with 3 bits; and   encoding or decoding the current coding unit using Intra motion compensated prediction based on reconstructed pixels of the current picture; and   if the Intra mode is selected for the current coding unit:   encoding or decoding the Intra mode using a fourth binary codeword with 3 bits; and   encoding or decoding the current coding unit using spatial prediction.   
     
     
         2 . The method of  claim 1 , wherein the first codeword, the second codeword, the third codeword and the fourth codeword correspond to {1, 00, 011, 010} respectively. 
     
     
         3 . A method of signaling of coding mode including an IntraBC mode (Intra-block copy mode) for a picture, wherein the picture is divided into multiple coding units, the method comprising:
 receiving input data associated with a current coding unit in a current slice of a current picture;   if the IntraBC mode is selected for the current coding unit:   encoding or decoding a partition mode associated with the IntraBC mode selected from a partition mode group for the current coding unit using a binary sub-tree representing all members of the partition mode group and the binary sub-tree consists of only said all members of the partition mode group; and   encoding or decoding the current coding unit according to the partition mode selected using Intra motion compensated prediction based on reconstructed pixels of the current picture, wherein the current coding unit is partitioned into multiple sub-blocks according to the partition mode.   
     
     
         4 . The method of  claim 3 , wherein the partition mode group consists of a 2N×2N mode indicating no partitioning, a 2N×M mode for partitioning each 2N×2N block horizontally into (2N/M) sub-blocks of size 2N×M, and an M×2N mode for partitioning each 2N×2N block vertically into (2N/M) sub-blocks of size M×2N, and wherein N and M are positive integers and M is not larger than N. 
     
     
         5 . The method of  claim 4 , wherein M is a power-of-2 integer. 
     
     
         6 . The method of  claim 4 , wherein the binary sub-tree for the 2N×2N mode, the 2N×M mode and the M×2N mode corresponds to {1, 01, 00} respectively. 
     
     
         7 . The method of  claim 3 , wherein the partition mode group consists of a 2N×2N mode, a 2N×N mode, an N×2N mode, and an N×N mode. 
     
     
         8 . The method of  claim 7 , wherein the binary sub-tree for the 2N×2N mode, the 2N×N mode, the N×2N mode and the N×N mode corresponds to {1, 01, 001, 000} respectively or {1, 001, 01, 000} respectively. 
     
     
         9 . The method of  claim 3 , wherein the partition mode group consists of a 2N×2N mode, a 2N×N mode and an N×2N mode when the current coding unit is larger than 8×8. 
     
     
         10 . The method of  claim 9 , wherein the binary sub-tree for the 2N×2N mode, the 2N×N mode and the N×2N mode corresponds to {1, 01, 00} respectively or {1, 00, 01} respectively. 
     
     
         11 . The method of  claim 3 , wherein the partition mode group consists of a 2N×2N mode, a 2N×N mode, a N×2N mode, an nL×2N mode, an nR×2N mode, a 2N×nU mode and a 2N×nD mode if the current coding unit is larger than 8×8. 
     
     
         12 . The method of  claim 11 , wherein the binary sub-tree for the 2N×2N mode, the 2N×N mode, the N×2N mode, the nL×2N mode, the nR×2N mode, the 2N×nU mode and the 2N×nD mode corresponds to {1, 011, 001, 0100, 0101, 0000, 0001} respectively or {1, 001, 011, 0000, 0001, 0100, 0101} respectively. 
     
     
         13 . The method of  claim 3 , wherein an enable flag is incorporated in a sequence level, a picture level, or a slice level of a bitstream to indicate whether the partition mode group is allowed to include one or more non-square partition modes for a corresponding sequence, a corresponding picture, or a corresponding slice. 
     
     
         14 . The method of  claim 3 , wherein an enable flag is incorporated in a sequence level, a picture level, or a slice level of a bitstream to indicate whether the partition mode group is allowed to include one or more asymmetric partition modes for a corresponding sequence, a corresponding picture, or a corresponding slice. 
     
     
         15 . The method of  claim 3 , wherein an enable flag is incorporated in a sequence level, a picture level, or a slice level of a bitstream to indicate whether the partition mode group is allowed to include one or more multiple partition modes to partition the coding unit into more than two sub-blocks for a corresponding sequence, a corresponding picture, or a corresponding slice. 
     
     
         16 . The method of  claim 3 , wherein an enable flag is incorporated in a sequence level, a picture level, or a slice level of a bitstream to indicate a total number of sub-blocks that the coding unit is partitioned according to the total number of sub-blocks for a corresponding sequence, a corresponding picture, or a corresponding slice.