Adaptive gop structure using temporal dependencies likelihood
AssigneeGoogle Inc.
InventorsChing Yin Derek Pang, Yeping Su, Yao-Chung Lin
Life of this patent
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Abstract
A first aspect is a method for coding a group of pictures (GOP) that includes frames of a video. The method includes encoding, at least some of the frames of the GOP, using a first encoding pass to obtain encoding statistics; obtaining, using the encoding statistics, respective temporal dependency likelihoods (TDLs) for the at least some of the frames of the GOP, where the respective TDLs indicate contributions that the at least some of the frames make in reducing prediction errors of the GOP; obtaining a reference frame based on the respective TDLs; and using the reference frame in encoding at least some of the frames of the GOP in a second encoding pass.
Claims20
A method for coding a group of pictures (GOP) that includes frames of a video, comprising:
- encoding, at least some of the frames of the GOP, using a first encoding pass to obtain encoding statistics;
- obtaining, using the encoding statistics, respective temporal dependency likelihoods (TDLs) for the at least some of the frames of the GOP, wherein the respective TDLs indicate contributions that the at least some of the frames make in reducing prediction errors of the GOP;
- obtaining a reference frame based on the respective TDLs;
- and
- using the reference frame in encoding at least some of the frames of the GOP in a second encoding pass.
An apparatus for encoding a group of pictures (GOP) that includes frames of a video, comprising:
- a processor configured to:
- obtain, during a first pass encoding, first respective temporal dependency likelihoods (TDLs) for the frames of the GOP excluding a first frame of the GOP,
- wherein a TDL of a frame of the GOP is a measure of a prediction error when the frame is used as a reference frame for encoding frames of the GOP, and
- wherein the first frame of the GOP is an intra-predicted frame;
- obtain a first reference frame using a frame of the GOP corresponding to a highest TDL of the TDLs;
- and
- encode, as a first encoding layer, the intra-predicted frame and the first reference frame in a second pass encoding;
- and
- encode, as a second encoding layer, a first subset of the frames of the GOP using the intra-predicted frame and the first reference frame in the second pass encoding.
An apparatus for decoding a group of pictures (GOP) that includes frames of a video, comprising:
- a processor configured to:
- decode a reference frame from a compressed bitstream;
- and
- decode at least one of frames of the GOP using the reference frame, wherein an encoder encoded the reference frame in the compressed bitstream by operations including operations to:
- encode, at least some of the frames of the GOP, using a first encoding pass to obtain encoding statistics;
- obtain, using the encoding statistics, respective temporal dependency likelihoods (TDLs) for the at least some of the frames of the GOP, wherein the respective TDLs indicate contributions that the at least some of the frames make in reducing prediction errors of the GOP;
- obtain the reference frame based on the respective TDLs;
- and
- use the reference frame in encoding at least some of the frames of the GOP in a second encoding pass.
Dependencies are inferred from the claim text.