Inferring motion vector predictor based on motion vector difference

A method comprising:

• decoding a motion information difference for a current block from video data;
• applying a validity checking process comprising determining that a first motion information predictor of a list of motion information predictors of the current block and the motion information difference form an invalid combination, the first motion information predictor of the list and the motion information difference forming an invalid combination if it is determined that a first value representative of a multiplication of the motion information difference by a difference between the first motion information predictor and a second motion information predictor of the list is larger than a second value representative of a norm of a difference between the first motion information predictor and the second motion information predictor;
• inferring a value representing the motion information predictor of the list to apply to predict a motion information of the current block responsive to the motion information difference and one of the first and the second motion information predictor of the list form an invalid combination;
• or
• decoding the value representing the motion information predictor of the list to apply to predict the motion information of the current block from the video data responsive to a combination of each motion information predictor of the list and the motion information is valid;
• and,
• reconstructing the motion information of the current block as a sum of the motion information difference and the motion information predictor of the list identified by the value.

A method comprising:

• obtaining a first motion information predictor of a list of motion information predictors of a current block of a picture for predicting motion information of a current block;
• calculating a motion information difference between the motion information of the current block and the first motion information predictor;
• encoding the motion information difference in video data;
• and
• applying a validity checking process comprising determining from a criterion calculated from the motion information difference and the motion information predictors of the list that a second motion information predictor of list and the motion information difference form a valid combination;
• and
• encoding a value representing the first motion information predictor only responsive to the second motion information predictor and the motion information difference form a valid combination.

A device comprising electronic circuitry configured for:

• decoding a motion information difference for a current block from video data;
• applying a validity checking process comprising determining that a first motion information predictor of a list of motion information predictors of the current block and the motion information difference form an invalid combination, the first motion information predictor of the list and the motion information difference forming an invalid combination if it is determined that a first value representative of a multiplication of the motion information difference by a difference between the first motion information predictor and a second motion information predictor of the list is larger than a second value representative of a norm of a difference between the first motion information predictor and the second motion information predictor;
• inferring a value representing the motion information predictor of the list to apply to predict a motion information of the current block responsive to the motion information difference and one of the first and the second motion information predictor of the list form an invalid combination;
• or
• decoding the value representing the motion information predictor of the list to apply to predict the motion information of the current block from the video data responsive to a combination of each motion information predictor of the list and the motion information is valid;
• and
• reconstructing the motion information of the current block as a sum of the motion information difference and the motion information predictor of the list identified by the value.

A device comprising electronic circuitry configured for:

• obtaining a first motion information predictor of a list of motion information predictors of a current block of a picture for predicting motion information of a current block;
• calculating a motion information difference between the motion information of the current block and the first motion information predictor;
• encoding the motion information difference in video data;
• and
• applying a validity checking process comprising determining that a second motion information predictor of the list and the motion information difference form a valid combination, the second motion information predictor of the list and the motion information difference forming an invalid combination if it is determined that a first value representative of a multiplication of the motion information difference by a difference between the first motion information predictor and a second motion information predictor of the list is larger than a second value representative of a norm of a difference between the first motion information predictor and the second motion information predictor;
• and
• encoding a value representing the first motion information predictor only responsive to the second motion information predictor and the motion information difference form a valid combination.