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

A moving picture coding method using a triangle merge mode, the moving picture coding method comprising:

• a triangle merging candidate list constructing step for constructing a triangle merging candidate list including spatial merging candidates;
• a first triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a first triangle merging candidate that is used for uni-prediction partition 0 which consists of subblocks above a diagonal line of the triangle partition splitting a coding block;
• a second triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a second triangle merging candidate that is used for uni-prediction partition 1 which consists of subblocks below the diagonal line;
• and
• a coding step for coding a first triangle merging index and a second triangle merging index,
• wherein in bi-prediction partition 2 which consists of subblocks on the diagonal line where motion compensation by weighted averaging by the first triangle merging candidate and the second triangle merging candidate is performed, uni-prediction motion information of the second triangle merging candidate is stored in a coding information storage memory so that the uni-prediction motion information of the second triangle merging candidate can be referred to as inter prediction information neighboring the coding block without storing bi-prediction motion information which is converted from motion information of list L0 and motion information of list L1.

A non-transitory computer-readable medium storing a moving picture coding program using a triangle merge mode, that in response to execution, causes a computer to perform operations comprising:

• a triangle merging candidate list constructing step for constructing a triangle merging candidate list including spatial merging candidates;
• a first triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a first triangle merging candidate that is used for uni-prediction partition 0 which consists of subblocks above a diagonal line of the triangle partition splitting a coding block;
• a second triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a second triangle merging candidate that is used for uni-prediction partition 1 which consists of subblocks below the diagonal line;
• and
• a coding step for coding a first triangle merging index and a second triangle merging index,
• wherein in bi-prediction partition 2 which consists of subblocks on the diagonal line where motion compensation by weighted averaging by the first triangle merging candidate and the second triangle merging candidate is performed, uni-prediction motion information of the second triangle merging candidate is stored in a coding information storage memory so that the uni-prediction motion information of the second triangle merging candidate can be referred to as inter prediction information neighboring the coding block without storing bi-prediction motion information which is converted from motion information of list L0 and motion information of list L1.

A moving picture decoding device using a triangle merge mode, the moving picture decoding device comprising:

• a decoding unit structured to decode a first triangle merging index and a second triangle merging index;
• a triangle merging candidate list constructor structured to construct a triangle merging candidate list including spatial merging candidates;
• a first triangle merging candidate selector structured to select, from the triangle merging candidate list, a first triangle merging candidate that is used for uni-prediction partition 0 which consists of subblocks above a diagonal line of the triangle partition splitting a coding block;
• and
• a second triangle merging candidate selector structured to select, from the triangle merging candidate list, a second triangle merging candidate that is used for uni-prediction partition 1 which consists of subblocks below the diagonal line,
• wherein in bi-prediction partition 2 which consists of subblocks on the diagonal line where motion compensation by weighted averaging by the first triangle merging candidate and the second triangle merging candidate is performed, uni-prediction motion information of the second triangle merging candidate is stored in a coding information storage memory so that the uni-prediction motion information of the second triangle merging candidate can be referred to as inter prediction information neighboring the coding block without storing bi-prediction motion information which is converted from motion information of list L0 and motion information of list L1.

A moving picture decoding method using a triangle merge mode, the moving picture decoding method comprising:

• a decoding step for decoding a first triangle merging index and a second triangle merging index;
• a triangle merging candidate list constructing step for constructing a triangle merging candidate list including spatial merging candidates;
• a first triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a first triangle merging candidate that is used for uni-prediction partition 0 which consists of subblocks above a diagonal line of the triangle partition splitting a coding block;
• and
• a second triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a second triangle merging candidate that is used for uni-prediction partition 1 which consists of subblocks below the diagonal line,
• wherein in bi-prediction partition 2 which consists of subblocks on the diagonal line where motion compensation by weighted averaging by the first triangle merging candidate and the second triangle merging candidate is performed, uni-prediction motion information of the second triangle merging candidate is stored in a coding information storage memory so that the uni-prediction motion information of the second triangle merging candidate can be referred to as inter prediction information neighboring the coding block without storing bi-prediction motion information which is converted from motion information of list L0 and motion information of list L1.

A non-transitory computer-readable medium storing a moving picture decoding program using a triangle merge mode, that in response to execution, causes a computer to perform operations comprising:

• a decoding step for decoding a first triangle merging index and a second triangle merging index;
• a triangle merging candidate list constructing step for constructing a triangle merging candidate list including spatial merging candidates;
• a first triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a first triangle merging candidate that is used for uni-prediction partition 0 which consists of subblocks above a diagonal line of the triangle partition splitting a coding block;
• and
• a second triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a second triangle merging candidate that is used for uni-prediction partition 1 which consists of subblocks below the diagonal line,
• wherein in bi-prediction partition 2 which consists of subblocks on the diagonal line where motion compensation by weighted averaging by the first triangle merging candidate and the second triangle merging candidate is performed, uni-prediction motion information of the second triangle merging candidate is stored in a coding information storage memory so that the uni-prediction motion information of the second triangle merging candidate can be referred to as inter prediction information neighboring the coding block without storing bi-prediction motion information which is converted from motion information of list L0 and motion information of list L1.

A storing method for storing a bitstream generated by a moving picture coding method using a triangle merge mode in a recording medium, the moving picture coding method comprising,

• a triangle merging candidate list constructing step for constructing a triangle merging candidate list including spatial merging candidates;
• a first triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a first triangle merging candidate that is used for uni-prediction partition 0 which consists of subblocks above a diagonal line of the triangle partition splitting a coding block;
• a second triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a second triangle merging candidate that is used for uni-prediction partition 1 which consists of subblocks below the diagonal line;
• and
• a coding step for coding a first triangle merging index and a second triangle merging index,
• wherein in bi-prediction partition 2 which consists of subblocks on the diagonal line where motion compensation by weighted averaging by the first triangle merging candidate and the second triangle merging candidate is performed, uni-prediction motion information of the second triangle merging candidate is stored in a coding information storage memory so that the uni-prediction motion information of the second triangle merging candidate can be referred to as inter prediction information neighboring the coding block without storing bi-prediction motion information which is converted from motion information of list L0 and motion information of list L1.

A transmitting method for transmitting a bitstream generated by a moving picture coding method using a triangle merge mode, the moving picture coding method comprising:

• a triangle merging candidate list constructing step for constructing a triangle merging candidate list including spatial merging candidates;
• a first triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a first triangle merging candidate that is used for uni-prediction partition 0 which consists of subblocks above a diagonal line of the triangle partition splitting a coding block;
• a second triangle merging candidate selecting step for selecting, from the triangle merging candidate list, a second triangle merging candidate that is used for uni-prediction partition 1 which consists of subblocks below the diagonal line;
• and
• a coding step for coding a first triangle merging index and a second triangle merging index,
• wherein in bi-prediction partition 2 which consists of subblocks on the diagonal line where motion compensation by weighted averaging by the first triangle merging candidate and the second triangle merging candidate is performed, uni-prediction motion information of the second triangle merging candidate is stored in a coding information storage memory so that the uni-prediction motion information of the second triangle merging candidate can be referred to as inter prediction information neighboring the coding block without storing bi-prediction motion information which is converted from motion information of list L0 and motion information of list L1.