US 12,335,527 B2
Transform-skip residual coding of video data
Mohammed Golam Sarwer, San Mateo, CA (US); Yan Ye, San Mateo, CA (US); and Jiancong Luo, San Mateo, CA (US)
Assigned to Alibaba Group Holding Limited, Grand Cayman (KY)
Filed by ALIBABA GROUP HOLDING LIMITED, Grand Cayman (KY)
Filed on May 30, 2024, as Appl. No. 18/679,306.
Application 18/679,306 is a continuation of application No. 16/872,643, filed on May 12, 2020, granted, now 12,041,270.
Claims priority of provisional application 62/953,460, filed on Dec. 24, 2019.
Claims priority of provisional application 62/902,115, filed on Sep. 18, 2019.
Claims priority of provisional application 62/865,916, filed on Jun. 24, 2019.
Prior Publication US 2024/0323443 A1, Sep. 26, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/645 (2014.01); H04N 19/176 (2014.01); H04N 19/18 (2014.01)
CPC H04N 19/645 (2014.11) [H04N 19/176 (2014.11); H04N 19/18 (2014.11)] 20 Claims
OG exemplary drawing
 
1. A coding method implemented by an encoder of video data, the method comprising:
performing a first pass of scanning a plurality of transform coefficients of a sub-block of a video frame, wherein coding of the sub-block is executed by multiple passes of scanning of the sub-block including the first pass of scanning and a second pass of scanning, the first pass of scanning comprising:
determining whether a remaining number of context coded bins (MaxCcbs) being greater than or equal to 4; and
in response to the remaining number of context coded bins being greater than or equal to 4, performing:
coding a sig_coeff_flag for a current transform coefficient, the sig_coeff_flag indicating whether a level of the current transform coefficient is zero; and
in response to the level of the current transform coefficient being not zero, coding a coeff_sign_flag and an abs_level_gtx_flag[0] for the current transform coefficient, the coeff_sign_flag representing the sign of the level of the current transform coefficient and the abs_level_gtx_flag[0] representing the absolute value of the level of the current transform coefficient is greater than 1; and
performing the second pass of scanning the plurality of transform coefficients of the sub-block of the video frame, the second pass of scanning comprising:
in response to the abs_level_gtx_flag[0] for the current transform coefficient being equal to 1, coding an abs_level_gtx_flag[1] for the current transform coefficient, the abs_level_gtx_flag[1] indicating whether the absolute value of the level of the current transform coefficient is greater than 3;
in response to the abs_level_gtx_flag[1] for the current transform coefficient being equal to 1, coding an abs_level_gtx_flag[2] for the current transform coefficient, the abs_level_gtx_flag[2] indicating whether the absolute value of the level of the current transform coefficient is greater than 5;
in response to the abs_level_gtx_flag[2] for the current transform coefficient being equal to 1, coding an abs_level_gtx_flag[3] for the current transform coefficient, the abs_level_gtx_flag[3] indicating whether the absolute value of the level of the current transform coefficient is greater than 7; and
in response to the abs_level_gtx_flag[3] for the current transform coefficient being equal to 1, coding an abs_level_gtx_flag[4] for the current transform coefficient, the abs_level_gtx_flag[4] indicating whether the absolute value of the level of the current transform coefficient is greater than 9.