Moving picture coding device, moving picture coding method, moving picture coding program, moving picture decoding device, moving picture decoding method, and moving picture decoding program

1. A moving picture coding device adapted to encode a coding block consisting of two prediction blocks, comprising:

a coding unit configured to encode an index into a bitstream, the index is specifying a merging motion information candidate used in a prediction block subject to encoding;

a merging motion information candidate list generation unit configured to generate a merging motion information candidate list including a plurality of merging motion information candidates for all the prediction blocks in the coding block using candidate blocks not neighboring the prediction block but neighboring the coding block, when a size of the coding block is smaller than a threshold size;

a merging motion information selection unit configured to select one merging motion information candidate from the merging motion information candidate list and to decide the index; and

a processing unit including the coding unit, the merging motion information candidate list generation unit, and the merging motion information selection unit,

wherein the merging motion information candidate list generation unit configured to generate the merging motion information candidate list including a plurality of merging motion information candidates for the prediction block using candidate blocks neighboring the prediction block, when the size of the coding block is larger than or equal to the threshold size.

2. A moving picture coding method adapted to encode a coding block consisting of two prediction blocks, comprising:

encoding an index into a bitstream, the index is specifying a merging motion information candidate used in a prediction block subject to encoding;

generating a merging motion information candidate list including a plurality of merging motion information candidates for all the prediction blocks in the coding block using candidate blocks not neighboring the prediction block but neighboring the coding block, when a size of the coding block is smaller than a threshold size; and

selecting one merging motion information candidate from the merging motion information candidate list and deciding the index,

wherein said generating the merging motion information candidate list generates the merging motion information candidate list including a plurality of merging motion information candidates for the prediction block using candidate blocks neighboring the prediction block, when the size of the coding block is larger than or equal to the threshold size.

3. A non-transitory computer-readable recording medium having embodied thereon a moving picture coding program adapted to encode a coding block consisting of two prediction blocks, the moving picture coding program causing a computer to execute:

encoding an index into a bitstream, the index is specifying a merging motion information candidate used in a prediction block subject to encoding;

generating a merging motion information candidate list including a plurality of merging motion information candidates for all the prediction blocks in the coding block using candidate blocks not neighboring the prediction block but neighboring the coding block, when a size of the coding block is smaller than a threshold size; and

selecting one merging motion information candidate from the merging motion information candidate list and deciding the index,

wherein said generating the merging motion information candidate list generates the merging motion information candidate list including a plurality of merging motion information candidates for the prediction block using candidate blocks neighboring the prediction block, when the size of the coding block is larger than or equal to the threshold size.

4. A moving picture decoding device adapted to decode a decoding block consisting of two prediction blocks, comprising:

a decoding unit configured to decode an index from a bitstream, the index is specifying a merging motion information candidate used in a prediction block subject to decoding,

a merging motion information candidate list generation unit configured to generate a merging motion information candidate list including a plurality of merging motion information candidates for all the prediction blocks in the decoding block using candidate blocks not neighboring the prediction blocks but neighboring the decoding block, when the size of the decoding block is smaller than a threshold size;

a merging motion information selection unit configured to select one merging motion information candidate from the merging motion information candidate list based on the index; and

a processing unit including the decoding unit, the merging motion information candidate list generation unit, and the merging motion information selection unit,

wherein the merging motion information candidate list generation unit configured to generate the merging motion information candidate list including a plurality of merging motion information candidates for the prediction block using candidate blocks neighboring the prediction block, when the size of the decoding block is larger than or equal to the threshold size.

5. A moving picture decoding method adapted to decode a decoding block consisting of two prediction blocks, comprising:

decoding an index from a bitstream, the index is specifying a merging motion information candidate used in a prediction block subject to decoding;

generating a merging motion information candidate list including a plurality of merging motion information candidates for all the prediction blocks in the decoding block using candidate blocks not neighboring the prediction block but neighboring the decoding block, when a size of the decoding block is smaller than a threshold size; and

selecting one merging motion information candidate from the merging motion information candidate list based on the index,

wherein said generating a merging motion information candidate list generates the merging motion information candidate list including a plurality of merging motion information candidates for the prediction block using candidate blocks neighboring the prediction block, when the size of the decoding block is larger than or equal to the threshold size.

6. A non-transitory computer-readable recording medium having embodied thereon a moving picture decoding program adapted to decode a decoding block consisting of two prediction blocks, the moving picture decoding program causing a computer to execute:

decoding an index from a bitstream, the index is specifying a merging motion information candidate used in a prediction block subject to decoding;

generating a merging motion information candidate list including a plurality of merging motion information candidates for all the prediction blocks in the decoding block using candidate blocks not neighboring the prediction block but neighboring the decoding block, when a size of the decoding block is smaller than a threshold size; and

selecting one merging motion information candidate from the merging motion information candidate list based on the index,

wherein said generating a merging motion information candidate list generates the merging motion information candidate list including a plurality of merging motion information candidates for the prediction block using candidate blocks neighboring the prediction block, when the size of the decoding block is larger than or equal to the threshold size.