Refined entropy coding for level maps
US10893280B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 22, 2019 |
| Grant date | Jan 12, 2021 |
| Priority date | — |
| Expiry date | Oct 22, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/122
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus includes a memory and a processor. The processor is configured to execute instructions stored in the memory to obtain a transform type for decoding a transform block for the current block; select, based on the transform type, a template for coding a value of a non-zero map; select, based on the template, a context for entropy decoding the value of the non-zero map; and decode the value of the non-zero map based on the context. The non-zero map indicates which coefficients of the transform block have non-zero values. A method includes obtaining a transform class for coding a transform block for the current block, wherein the transform class corresponding to a transform type and a direction; selecting, based on the transform class, a coding context for coding a value of a non-zero map; and coding the value of the non-zero map based on the coding context.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.