Moving picture coding method, moving picture decoding method, moving picture coding apparatus, moving picture decoding apparatus, and moving picture coding and decoding apparatus

1. An encoding and decoding device comprising:

a first processor; and

first non-transitory storage coupled to the first processor;

wherein the first processor is configured to perform the following:

obtaining a first luminance CBF flag indicating whether or not a first quantized coefficient is included in a first transform unit that is included in a first coding unit of a first image;

judging whether or not a size of the first coding unit is identical to a size of the first transform unit;

selecting a first probability table or a second probability table so that (i) the first probability table is selected when the size of the first coding unit is identical to the size of the first transform unit and (ii) the second probability table is selected when the size of the first coding unit is not identical to the size of the first transform unit regardless of the size of the first transform unit, the first probability table corresponding to a context increment value 1 and the second probability table corresponding to a context increment value 0;

performing arithmetic encoding on the first luminance CBF flag using the selected one of the first probability table and the second probability table; and

encoding a picture signal for the first coding unit using the first quantized coefficient of the first transform unit when the first luminance CBF flag indicates that the first quantized coefficient is included in the first transform unit,

wherein when the size of the first transform unit is a first size which is smaller than the size of the first coding unit, the selecting selects the second probability table,

wherein when the size of the first transform unit is a second size which is smaller than the first size, the selecting selects the second probability table without depending on any surrounding blocks,

wherein when the size of the first transform unit is smaller than a maximum size of the first transform unit, the selecting selects the second probability table without depending on any surrounding blocks, the maximum size of the first transform unit being indicated in a first bitstream,

wherein switching is performed between encoding conforming to a first codec standard and encoding conforming to a second codec standard according to a first identifier which is included in the first bitstream and indicates the first codec standard or the second codec standard, the second codec standard being different from the first codec standard,

wherein each of the first probability table and the second probability table includes probability tables for types of a slice, and

wherein, in the performing of arithmetic encoding, a probability table included in the selected one of the first probability table and the second probability table is used, the used probability table corresponding to a type of a slice to which the first coding unit belongs,

wherein the encoding and decoding device further comprises:

a second processor; and

second non-transitory storage coupled to the second processor;

wherein the second processor is configured to perform the following:

obtaining, from a coded signal, a second luminance CBF flag indicating whether or not a second quantized coefficient is included in a second transform unit that is included in a second coding unit of a second image;

judging whether or not a size of the second coding unit is identical to a size of the second transform unit;

selecting a third probability table or a fourth probability table so that (i) the third probability table is selected when the size of the second coding unit is identical to the size of the second transform unit and (ii) the fourth probability table is selected when the size of the second coding unit is not identical to the size of the second transform unit regardless of the size of the second transform unit, the third probability table corresponding to a context increment value 1 and the fourth probability table corresponding to a context increment value 0;

performing arithmetic decoding on the second luminance CBF flag using the selected one of the third probability table and the fourth probability table; and

decoding a picture signal for the second coding unit using the second quantized coefficient of the second transform unit when the second luminance CBF flag indicates that the second quantized coefficient is included in the second transform unit,

wherein when the size of the second transform unit is a third size which is smaller than the size of the second coding unit, the selecting selects the fourth probability table,

wherein when the size of the second transform unit is a fourth size which is smaller than the third size, the selecting selects the fourth probability table without depending on any surrounding blocks,

wherein when the size of the second transform unit is smaller than a maximum size of the second transform unit, the selecting selects the fourth probability table without depending on any surrounding blocks, the maximum size of the second transform unit being indicated in a second bitstream,

wherein switching is performed between decoding conforming to a third codec standard and decoding conforming to a fourth codec standard according to a second identifier which is included in the second bitstream and indicates the third codec standard or the fourth codec standard, the fourth codec standard being different from the third codec standard,

wherein each of the third probability table and the fourth probability table includes probability tables for types of a slice, and

wherein, in the performing of arithmetic coding, a probability table included in the selected one of the third probability table and the fourth probability table is used, the used probability table corresponding to a type of a slice to which the second coding unit belongs.