Constraints on locations of reference blocks for intra block copy prediction
US10986349B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 2018 |
| Grant date | Apr 20, 2021 |
| Priority date | — |
| Expiry date | Jan 31, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/593
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
When encoding/decoding a current block of a current picture using intra block copy (“BC”) prediction, the location of a reference block is constrained so that it can be entirely within an inner search area of the current picture or entirely within an outer search area of the current picture, but cannot overlap both the inner search area and the outer search area. In some hardware-based implementations, on-chip memory buffers sample values of the inner search area, and off-chip memory buffers sample values of the outer search area. By enforcing this constraint on the location of the reference block, an encoder/decoder can avoid memory access operations that are split between on-chip memory and off-chip memory when retrieving the sample values of the reference block. At the same time, a reference block close to the current block may be used for intra BC prediction, helping compression efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.