Time-variant multi-hypothesis probability model update for entropy coding
AssigneeGoogle Inc.
InventorsJingning Han, Yaowu Xu
Life of this patent
Estimating the term…
Abstract
A sequence of syntax elements is received. A symbol is determined for a syntax element of the sequence. The symbol is entropy coded using arithmetic coding based on a linear combination of a first probability model and a second probability model. The first probability model is updated using a first time-variant update rate to produce a first updated probability model for entropy coding a symbol for a subsequent syntax element of the sequence. The second probability model is updated using a second time-variant update rate, different from the first time-variant update rate, to produce a second updated probability model for entropy coding the symbol for the subsequent syntax element.
Claims20
A device for entropy coding a sequence of syntax elements, comprising:
- a processor configured to:
- receive the sequence of syntax elements;
- determine a symbol for a syntax element of the sequence;
- entropy code, using arithmetic coding, the symbol using a linear combination of a first probability model and a second probability model;
- update the first probability model using a first time-variant update rate to produce a first updated probability model for entropy coding a symbol for a subsequent syntax element of the sequence;
- and
- update the second probability model using a second time-variant update rate to produce a second updated probability model for entropy coding the symbol for the subsequent syntax element of the sequence, wherein the second time-variant update rate is different from the first time-variant update rate,
- wherein the first time-variant update rate provides a first higher adaptation rate at a beginning of use of the first probability model as compared to a first lower adaptation rate later in the use of the first probability model, and
- wherein the second time-variant update rate provides a second higher adaptation rate at a beginning of use of the second probability model as compared to a second lower adaptation rate later in the use of the second probability model.
A method for entropy coding a sequence of syntax elements, comprising:
- receiving the sequence of syntax elements;
- determining a symbol for a syntax element of the sequence;
- entropy coding, using arithmetic coding, the symbol using a linear combination of a first probability model and a second probability model;
- updating the first probability model using a first time-variant update rate to produce a first updated probability model for entropy coding a symbol for a subsequent syntax element of the sequence;
- and
- updating the second probability model using a second time-variant update rate to produce a second updated probability model for entropy coding the symbol for the subsequent syntax element of the sequence, wherein the second time-variant update rate is different from the first time-variant update rate,
- wherein the first time-variant update rate provides a first higher adaptation rate at a beginning of use of the first probability model as compared to a first lower adaptation rate later in the use of the first probability model, and
- wherein the second time-variant update rate provides a second higher adaptation rate at a beginning of use of the second probability model as compared to a second lower adaptation rate later in the use of the second probability model.
A non-transitory computer-readable storage medium, comprising executable instructions that, when executed by a processor, perform operations comprising:
- receiving a sequence of syntax elements;
- determining a symbol for a syntax element of the sequence;
- entropy coding, using arithmetic coding, the symbol using a linear combination of a first probability model and a second probability model;
- updating the first probability model using a first time-variant update rate to produce a first updated probability model for entropy coding a symbol for a subsequent syntax element of the sequence;
- and
- updating the second probability model using a second time-variant update rate to produce a second updated probability model for entropy coding the symbol for the subsequent syntax element of the sequence, wherein the second time-variant update rate is different from the first time-variant update rate,
- wherein the first time-variant update rate provides a first higher adaptation rate at a beginning of use of the first probability model as compared to a first lower adaptation rate later in the use of the first probability model, and
- wherein the second time-variant update rate provides a second higher adaptation rate at a beginning of use of the second probability model as compared to a second lower adaptation rate later in the use of the second probability model.
Dependencies are inferred from the claim text.