Patent ID: 9560352
Date: 2017-01-31
CPC Classifications: H04N

Claim:
1. An image coding method of coding a current block to be coded using a first reference index and a first motion vector, the first reference index indicating a first reference picture, the image coding method comprising: calculating, using a second reference index and a second motion vector, a third reference index and a third motion vector as respective first candidates for the first reference index and the first motion vector, the second reference index and the second motion vector being used to code a corresponding block that is included in a corresponding picture different from a current picture to be coded and whose position in the corresponding picture matches a position of the current block in the current picture; determining a value of a flag that indicates whether or not to code the current block using the third reference index and the third motion vector as the first reference index and the first motion vector; and coding the current block using the first reference index and the first motion vector according to the value of the flag, and adding the value of the flag to a bitstream generated by the coding, wherein in the case where a second reference picture indicated by the second reference index is not included in a reference picture list, a prediction direction from the current picture to the corresponding picture cannot be used.