Movie picture coding method, moving picture decoding method, moving picture coding apparatus, moving picture decoding apparatus, and moving picture coding and decoding apparatus
A moving picture coding method includes (i) transforming, for each of one or more second processing units included in the first processing unit, a moving picture signal in a spatial domain into a frequency domain coefficient and quantizing the frequency domain coefficient, and (ii) performing arithmetic coding on a luminance CBF flag indicating whether or not a quantized coefficient is included in the second processing unit in which transform and quantization are performed, wherein, in the arithmetic coding, a probability table for use in arithmetic coding is determined according to whether or not the size of the first processing unit is identical to the size of the second processing unit and whether or not the second processing unit has a predetermined maximum size.
1. A encoding device comprising:
at least one processor; and
non-transitory storage coupled to the at least one processor;
wherein the at least one processor is configured to perform the following:
obtaining a luminance CBF flag indicating whether or not a quantized coefficient is included in a transform unit that is included in a coding unit of the image;
judging whether or not a size of the coding unit is identical to a size of the 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 coding unit is identical to the size of the transform unit and (ii) the second probability table is selected when the size of the coding unit is not identical to the size of the transform unit regardless of the size of the 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 luminance CBF flag using the selected one of the first probability table and the second probability table; and
encoding a picture signal for the coding unit using the quantized coefficient of the transform unit when the luminance CBF flag indicates that the quantized coefficients is included in the transform unit,
wherein when the size of the transform unit is a first size which is smaller than the size of the coding unit, the selecting selects the second probability table,
wherein when the size of the 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 transform unit is smaller than a maximum size of the transform unit, the selecting selects the second probability table without depending on any surrounding blocks, the maximum size of the transform unit being indicated in the bitstream,
wherein switching is performed between encoding conforming to a first codec standard and encoding conforming to a second codec standard according to an identifier which is included in the 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 coding unit belongs.