Method and device for encoding/decoding motion vector

A method performed by a motion vector decoding apparatus for decoding a motion vector, the method comprising:

• determining a first predicted motion vector and a second predicted motion vector relating to a current block to be decoded;
• decoding information on a motion vector resolution;
• decoding a first differential motion vector and a second differential motion vector by using the decoded information on the motion vector resolution;
• reconstructing a first motion vector by adding the decoded first differential motion vector and the first predicted motion vector;
• and
• reconstructing a second motion vector by adding the decoded second differential motion vector and the second predicted motion vector.

A method performed by a motion vector encoding apparatus for encoding a motion vector, the method comprising:

• determining an inter prediction mode of a current block to be encoded, among prediction modes including a first prediction mode which uses a motion vector and a second prediction mode which uses a plurality of motion vectors;
• determining each resolution of one or more motion vectors of the current block;
• and
• encoding the one or more motion vectors based on the determined each resolution.

A method performed by a motion vector decoding apparatus for decoding a motion vector, the method comprising:

• determining an inter prediction mode of a current block to be decoded, among prediction modes including a first prediction mode which uses a motion vector and a second prediction mode which uses a plurality of motion vectors;
• determining each resolution of one or more motion vectors of the current block;
• and
• decoding the one or more motion vectors based on the determined each resolution.