Motion vector coding and decoding methods
A motion vector coding method and apparatus that improves efficiency of coding motion vectors when a current block is coded using a plurality of motion vectors. The apparatus includes a motion vector coding unit that codes a motion vector inputted from a motion vector detecting unit. A motion vector for each current block is coded based on a difference between the motion vector and a predicted vector obtained from motion vectors for previously coded neighboring blocks. The predicted vector is generated by one of the following processes: (A) the motion vectors which refer to the same picture are selected from among the motion vectors for the neighboring blocks so as to generate the predicted vector; (B) the motion vectors for the respective neighboring blocks are ordered in the predetermined order, and the motion vectors of the same order rank are selected from the ordered motion vectors so as to generate the predicted vector; and (C) the predicted vector for the second motion vector of the current block shall be the first motion vector, and if the second motion vector and the first motion vector refer to different pictures, the first motion vector is scaled according to the temporal distance between the pictures so as to generate the predicted vector.
1. An integrated circuit, comprising:
an audio processor configured to process digital audio data; and
an image decoder configured to decode coded image data,
wherein the image decoder includes:
an assigning unit configured to, when at least one block among a plurality of decoded blocks in the neighborhood of a current block has two motion vectors which refer to reference pictures in the same direction in a display order, assign an identifier to each motion vector for respective one of the plurality of decoded blocks;
a generating unit configured to generate a predicted motion vector for a motion vector of the current block based on the motion vectors with same identifier among the motion vectors for the plurality of decoded blocks; and
a decoding unit configured to decode a coded motion vector for the current block using the predicted motion vector.
2. A mobile terminal which comprises the integrated circuit of claim 1 .
3. The integrated circuit according to claim 1 , further comprising:
a control unit configured to output the decoded image data to a monitor,
wherein said audio processor is configured to output the processed digital audio data to a speaker simultaneously when said control unit outputs the decoded image data to the monitor.