Method for selecting output motion vector based on motion vector refinement and transcoder using the same

An output motion vector estimation method comprises the steps to perform the steps and the motion refinement for setting the step, steps, varying the search area for selecting at least two reference vectors forming a candidate motion vector group for estimating an output motion vector. Selecting at least two reference vectors, and variably setting a search area in accordance with the correlation of the reference vector Fig. Transcoder using the output motion vector estimation method is selected at least two reference vectors in encoding parameter estimator, and variably setting a search area in accordance with the correlation of the reference vector Fig. Thus, while reducing an increase in the amount of calculation can effectively set the search area can be estimated to output the motion vector precisely.