An apparatus for decoding a current block includes: a decoding unit to extract a first identification information from a bitstream, and reconstruct a quantized frequency residual block of the current block from the bitstream; a dequantization and inverse transform unit to dequantize and inversely transform the quantized frequency residual block to reconstruct a residual block of the current block; an inter prediction unit to generate the plurality of motion vector candidates of the current block from neighboring blocks of the current blocks, select a motion vector candidate from the plurality of motion vector candidates based on a second identification information, the second identification information being decoded from the bitstream, reconstruct the motion vector of the current block as the selected motion vector candidate, and generate a predicted block of the current block by using the reconstructed motion vector of the current block.