US 12,301,810 B2
Quantizer for lossless and near-lossless compression
Madhu Peringassery Krishnan, Mountain View, CA (US); Xin Zhao, Santa Clara, CA (US); and Shan Liu, San Jose, CA (US)
Assigned to TENCENT AMERICA LLC, Palo Alto, CA (US)
Filed by TENCENT AMERICA LLC, Palo Alto, CA (US)
Filed on Jun. 27, 2023, as Appl. No. 18/342,349.
Application 18/342,349 is a continuation of application No. 17/828,728, filed on May 31, 2022, granted, now 11,750,812.
Application 17/828,728 is a continuation of application No. 17/243,132, filed on Apr. 28, 2021, granted, now 11,381,821, issued on Jul. 5, 2022.
Application 17/243,132 is a continuation of application No. 17/065,974, filed on Oct. 8, 2020, granted, now 11,032,546, issued on Jun. 8, 2021.
Claims priority of provisional application 63/054,049, filed on Jul. 20, 2020.
Prior Publication US 2023/0336727 A1, Oct. 19, 2023
Int. Cl. H04N 19/124 (2014.01); H04N 19/12 (2014.01); H04N 19/85 (2014.01)
CPC H04N 19/124 (2014.11) [H04N 19/12 (2014.11); H04N 19/85 (2014.11)] 20 Claims
OG exemplary drawing
 
1. A method of video decoding, the method comprising:
obtaining a video bitstream indicating a plurality of syntax values, the syntax values comprising a base_q_idx syntax, a qindex_lossless syntax, and a DeltaQ syntax;
determining a change to at least one of an accessible qindex_lossless value, of the qindex_lossless syntax for a lossless mode, and a smallest accessible qindex value, for a lossy mode, depending on whether all of a sum, of a value of the base_q_idx syntax and a value of the DeltaQ syntax, is less than or equal to zero and one or more other conditions are met; and
decoding the video bitstream based on determining whether to apply the lossless mode or the lossy mode depending on any of the value of the base_q_idx syntax, a value of the qindex_lossless syntax, and the value of the DeltaQ syntax.