US 12,003,706 B2
Combination of mode-dependent and fixed transform types in video coding
Lester Lu, Los Angeles, CA (US); Debargha Mukherjee, Cupertino, CA (US); and Elliott Karpilovsky, Santa Clara, CA (US)
Assigned to GOOGLE LLC, Mountain View, CA (US)
Filed by Google LLC, Mountain View, CA (US)
Filed on Mar. 21, 2022, as Appl. No. 17/700,298.
Application 17/700,298 is a continuation of application No. 16/712,057, filed on Dec. 12, 2019, granted, now 11,284,071, issued on Mar. 22, 2022.
Prior Publication US 2022/0217336 A1, Jul. 7, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. H04N 19/107 (2014.01); H04N 19/122 (2014.01); H04N 19/176 (2014.01); H04N 19/50 (2014.01)
CPC H04N 19/107 (2014.11) [H04N 19/122 (2014.11); H04N 19/176 (2014.11); H04N 19/50 (2014.11)] 20 Claims
OG exemplary drawing
 
1. A method for decoding video data from a video bitstream, the method comprising:
for a respective block of a plurality of blocks encoded into the video bitstream using a prediction mode:
determining a transform mode for the block using the prediction mode, wherein:
the transform mode comprises a first transform mode responsive to the prediction mode being an inter-prediction mode,
the transform mode comprises a second transform mode responsive to the prediction mode being an intra-prediction mode of a plurality of available intra-prediction modes,
the first transform mode comprises one of a plurality of available first transform types, each of the plurality of available first transform types comprising respective combinations of transforms selected from the group consisting of:
first fixed transforms, each comprising a respective fixed transformation matrix, and
first mode-dependent, learned transforms, each comprising a respective transformation matrix that was generated iteratively using blocks predicted using the inter-prediction mode,
the second transform mode comprises one of a plurality of available second transform types, each of the plurality of available second transform types comprising respective combinations of transforms selected from the group consisting of:
second fixed transforms, each comprising a respective fixed transformation matrix, wherein the second fixed transforms comprise a proper subset of the first fixed transforms, and
a second mode-dependent, learned transform comprising a transformation matrix that is generated iteratively using blocks predicted using the intra-prediction mode; and
decoding the block using the prediction mode and the transform mode.