US 11,943,476 B2
Methods and apparatuses for coding video data with adaptive secondary transform signaling
Man-Shu Chiang, Hsinchu (TW); Chih-Wei Hsu, Hsinchu (TW); Tzu-Der Chuang, Hsinchu (TW); and Ching-Yeh Chen, Hsinchu (TW)
Assigned to HFI INNOVATION INC., Zhubei (TW)
Appl. No. 17/603,484
Filed by MEDIATEK INC., Hsinchu (TW)
PCT Filed Apr. 15, 2020, PCT No. PCT/CN2020/084896
§ 371(c)(1), (2) Date Oct. 13, 2021,
PCT Pub. No. WO2020/211776, PCT Pub. Date Oct. 22, 2020.
Claims priority of provisional application 62/834,487, filed on Apr. 16, 2019.
Prior Publication US 2022/0224898 A1, Jul. 14, 2022
Int. Cl. H04N 19/60 (2014.01); H04N 19/12 (2014.01); H04N 19/167 (2014.01); H04N 19/176 (2014.01); H04N 19/18 (2014.01); H04N 19/186 (2014.01); H04N 19/70 (2014.01)
CPC H04N 19/60 (2014.11) [H04N 19/12 (2014.11); H04N 19/167 (2014.11); H04N 19/176 (2014.11); H04N 19/18 (2014.11); H04N 19/186 (2014.11); H04N 19/70 (2014.11)] 17 Claims
OG exemplary drawing
 
17. An apparatus for performing video decoding, comprising: a computer processor configured for receiving video data; and programming executable on the computer processor for video coding by performing steps comprising:
receiving a video bitstream carrying input data associated with a current block in a current video picture, wherein the input data comprises final transform coefficients of the current block;
parsing one or more last significant coefficient position syntax for one or more Transform Blocks (TBs) associated with the current block from the video bitstream;
determining a position of a last significant coefficient for each TB from the parsed last significant coefficient position syntax;
comparing one or more positions of the last significant coefficients with a predefined position;
determining an inverse transform operation for the current block by inferring a secondary transform index as zero if the one or more positions of the last significant coefficients for one or more TBs are less than or equal to the predefined position, or by parsing a secondary transform index from the video bitstream if at least one of the positions of the last significant coefficients is larger than the predefined position;
applying at least inverse primary transform to the final transform coefficients of the current block to recover residuals of the current block according to the inverse transform operation; and
decoding the current block in the current video picture based on the residuals of the current block.