A method for decoding video information, the method comprising: decoding a prediction flag indicating whether information of a current block is the same as prediction information derived from information of a neighboring block reconstructed earlier than the current block, the neighboring block is one of spatial neighboring blocks and a collocated block, the spatial neighboring blocks belong to a current frame to which the current block belongs, and the collocated block belongs to a reference frame having a different temporal order from the current frame; deriving the information of the current block based on the decoded prediction flag; and performing inter-prediction on the current block based on the derived information of the current block, wherein the information of the current block includes information on a motion vector of the current block and information on a prediction direction of the current block, wherein the prediction information includes prediction information on a motion vector and prediction information on a prediction direction, wherein, when the prediction flag indicates the information of the current block is the same as the prediction information, the prediction information is used as the information of the current block, wherein, when the prediction flag indicates the information of the current block is not the same as the prediction information, the information of the current block is derived by adding a difference value obtained from a bitstream to the prediction information, wherein the inter-prediction is performed using one or more reference frames reconstructed earlier than the current frame, each of the reference frames has a different temporal order from the current frame and is identified by a reference index, and wherein, when the number of the reference frames is 2 and the number of reference frame lists constructed from the reference frames is 2, the reference index is determined as a specific value indicating each of the reference frames. decoding a prediction flag indicating whether information of a current block is the same as prediction information derived from information of a neighboring block reconstructed earlier than the current block, the neighboring block is one of spatial neighboring blocks and a collocated block, the spatial neighboring blocks belong to a current frame to which the current block belongs, and the collocated block belongs to a reference frame having a different temporal order from the current frame; deriving the information of the current block based on the decoded prediction flag; and performing inter-prediction on the current block based on the derived information of the current block, wherein the information of the current block includes information on a motion vector of the current block and information on a prediction direction of the current block, wherein the prediction information includes prediction information on a motion vector and prediction information on a prediction direction, wherein, when the prediction flag indicates the information of the current block is the same as the prediction information, the prediction information is used as the information of the current block, wherein, when the prediction flag indicates the information of the current block is not the same as the prediction information, the information of the current block is derived by adding a difference value obtained from a bitstream to the prediction information, wherein the inter-prediction is performed using one or more reference frames reconstructed earlier than the current frame, each of the reference frames has a different temporal order from the current frame and is identified by a reference index, and wherein, when the number of the reference frames is 2 and the number of reference frame lists constructed from the reference frames is 2, the reference index is determined as a specific value indicating each of the reference frames.