CPC H04N 19/513 (2014.11) [H04N 19/52 (2014.11); H04N 19/70 (2014.11)] | 3 Claims |
1. An image decoding device for decoding coded image, the image decoding device comprising:
prediction parameter decoding control circuitry that decodes:
(i) an affine flag specifying whether an affine prediction is used for a target unit, based on a target block width being greater than or equal to 16, and
(ii) motion vector difference information based on a value of the affine flag; and
candidate derivation circuitry that derives:
(i) a first motion vector predictor and a second motion vector predictor, in a case that the affine flag indicates that the affine prediction being used for the target unit,
(ii) (a) a first control point motion vector by using a sum of the first motion vector predictor and a first difference motion vector and (b) a second control point motion vector by using a sum of the second motion vector predictor and a second difference motion vector, and
(iii) a motion vector for a sub-block by using the first control point motion vector and the second control point motion vector; and
wherein
each of the first difference motion vector and the second difference motion vector is derived by using a first syntax element, a second syntax element and a third syntax element,
the first syntax element specifies whether an absolute value of a difference motion vector is greater than zero,
the second syntax element plus two specifies the absolute value of the difference motion vector, and
the third syntax element, specifies a sign of the difference motion vector.
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