An apparatus and method determining a motion vector for a block, which relates to motion vector determination employing template matching or bilateral matching, are provided. At first, candidate motion vectors are obtained and are mapped to respective representatives (representative motion vectors). In particular, if the obtained candidate motion vectors point to fractional positions and thus, interpolation from the integer sample positions is required, the initial motion vector is rounded to a closest integer sample position. The rounded position is then used to define the search space for the template or bilateral matching to determine the best matching motion vector for the block (in other words, a refinement of an initial motion vector around which the candidate space is spanned). Finally, the mapping operation can be reverted in order to obtain a result in the original search space.