Abstract:
An image coding method includes coding first binary data indicating a first intra prediction mode and second binary data indicating a second intra prediction mode (S801), wherein in the coding (S801), a first context adaptive portion which is part of the first binary data and a second context adaptive portion which is part of the second binary data are coded by context adaptive binary arithmetic coding, a first bypass portion which is different part of the first binary data and a second bypass portion which is different part of the second binary data are coded by bypass coding, and coded data is generated which includes the first context adaptive portion, the second context adaptive portion, the first bypass portion, and the second bypass portion, the first bypass portion and the second bypass portion being included subsequent to the first context adaptive portion and the second context adaptive portion.
Abstract:
The image decoding method includes: determining a context for use in a current block, from among a plurality of contexts (S204); and performing arithmetic decoding on a bit sequence corresponding to the current block, using the determined context (S210), wherein in the determining (S204): the context is determined under a condition that control parameters of neighboring blocks of the current block are used, when the signal type is a first type, the neighboring blocks being a left block and an upper block of the current block (S206); and the context is determined under a condition that the control parameter of the upper block is not used, when the signal type is a second type (S207), and the second type is "no_residual_data_flag".
Abstract:
An image coding method includes (S801) coding a motion vector difference indicating a difference between the motion vector and a predicted motion vector, wherein the coding (S801) includes: coding a first portion that is a part of a first component which is one of a horizontal component and a vertical component of the motion vector difference; coding a second portion that is a part of a second component which is different from the first component and is the other one of the horizontal component and the vertical component; coding a third portion that is a part of the first component and is different from the first portion; coding a fourth portion that is a part of the second component and is different from the second portion; and generating a code string which includes the first portion, the second portion, the third portion, and the fourth portion in the stated order.