Method of decoding motion vector

Abstract

An apparatus of encoding an image in an advanced motion vector prediction (AMVP) mode can include an inter prediction module for determining motion information of a current block, and generating a prediction block of the current block using the motion information; a transform module for transforming the residual block to generate a transformed block; a quantization module for quantizing the transformed block using a quantization parameter and a quantization matrix to generate a quantized block; a scanning module for scanning quantized coefficient components of the quantized block; and an entropy coding module for entropy-coding the scanned quantized coefficient components of the quantized block; in which the motion information is encoded by performing the sub-steps of: constructing an AMVP list using available motion vector candidates of a left motion vector candidate, an above motion vector candidate and a temporal motion vector candidate; selecting a motion vector predictor among motion vector candidates of the AMVP candidate list; generating a differential motion vector by subtracting the motion vector predictor from the motion vector; and encoding a reference picture index, the differential motion vector and an AMVP index specifying the motion vector predictor.