decoding, from a bitstream carrying a video comprising a current picture, a signal indicative of a subblock based intra block copy (IBC) merge mode for predicting a current block in the current picture, the current block comprising a plurality of subblocks;

checking spatial neighbors according to a checking order for a first available block vector;

determining a predictor offset according to the first available block vector of a spatial neighbor of the current block, the predictor offset indicating a predictor block in the current picture corresponding to the current block, the predictor block comprising a plurality of predictor subblocks with block vector information respectively; and

reconstructing a subblock in the current block according to the first available block vector that points to a reference block for the subblock in the current picture.