receiving a bit stream; and

performing an adaptive decoding for a target block based on the received bit stream,

wherein the adaptive decoding determines a quantization parameter of the target block based on quantization parameters of referencing blocks, and performs the decoding for the target block based on the determined quantization parameter of the target block,

wherein the reference blocks comprise a block adjacent to the left of the target block and a block adjacent to the above of the target block,

wherein, the quantization parameters of the reference blocks are determined to be used based on a position of the reference blocks,

wherein the quantization parameter of the target block is determined by a calculation formula using the quantization parameters of the reference blocks.