US 12,262,017 B2
Video encoding and decoding using differential modulation
Je Won Kang, Seoul (KR); Seung Wook Park, Yongin-si (KR); and Wha Pyeong Lim, Hwaseong-si (KR)
Assigned to HYUNDAI MOTOR COMPANY, Seoul (KR); KIA CORPORATION, Seoul (KR); and EWHA UNIVERSITY—INDUSTRY COLLABORATION FOUNDATION, Seoul (KR)
Filed by HYUNDAI MOTOR COMPANY, Seoul (KR); KIA CORPORATION, Seoul (KR); and EWHA UNIVERSITY—INDUSTRY COLLABORATION FOUNDATION, Seoul (KR)
Filed on May 27, 2022, as Appl. No. 17/826,302.
Application 17/826,302 is a continuation of application No. PCT/KR2020/017428, filed on Dec. 2, 2020.
Claims priority of application No. 10-2019-0158563 (KR), filed on Dec. 2, 2019; and application No. 10-2020-0166249 (KR), filed on Dec. 2, 2020.
Prior Publication US 2022/0286686 A1, Sep. 8, 2022
Int. Cl. H04N 19/132 (2014.01); H04N 19/105 (2014.01); H04N 19/159 (2014.01); H04N 19/176 (2014.01); H04N 19/186 (2014.01); H04N 19/46 (2014.01); H04N 19/70 (2014.01)
CPC H04N 19/132 (2014.11) [H04N 19/105 (2014.11); H04N 19/159 (2014.11); H04N 19/176 (2014.11); H04N 19/186 (2014.11); H04N 19/46 (2014.11); H04N 19/70 (2014.11)] 14 Claims
OG exemplary drawing
 
1. A method for decoding a bitstream encoded from a video sequence comprising a plurality of pictures, the method comprising:
decoding, from a sequence parameter set of the bitstream, information on a chroma sampling format and high level syntax elements related to differential modulation for residual signals,
wherein the information on the chroma sampling format indicates one of a plurality of chroma sampling formats including 4:4:4, 4:2:2, or 4:2:0, and
wherein the high level syntax elements comprise a single common control flag indicating whether the differential modulation is permitted for the residual signals of each of luma and chroma components of the video sequence and information on a maximum block size for which the differential modulation is permitted;
decoding a first chroma syntax element indicating whether the differential modulation has been applied to a chroma block corresponding to a first block to be currently decoded, when the first block satisfies conditions defined by the information on the chroma sampling format and the high level syntax elements;
decoding a second chroma syntax element indicating a differential modulation direction applied to the chroma block in response to the first chroma syntax element indicating that the differential modulation has been applied to the chroma block;
determining a differential-modulated residual block for the chroma block from the bitstream;
determining quantized residual values by differential-demodulating the differential- modulated residual block in the differential modulation direction indicated by the second chroma syntax element;
inversely quantizing the quantized residual values for the chroma block;
generating predicted values for the chroma block; and
reconstructing the chroma block corresponding to the first block based on the inversely quantized residual values and the predicted values,
wherein the conditions defined by the information on the chroma sampling format and the high level syntax elements are satisfied when:
(1) the single common control flag indicates that the differential modulation is permitted for the video sequence,
(2) a value obtained by dividing a width of the first block by a horizontal scaling factor determined by the chroma sampling format that the information on the chroma sampling format indicates among the plurality of chroma sampling formats is smaller than or equal to the maximum block size, and
(3) a value obtained by dividing a height of the first block by a vertical scaling factor determined by the chroma sampling format indicated by the information on the chroma sampling format is smaller than or equal to the maximum block size.