Image sequence coding method and decoding method
US6295376A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 8, 1998 |
| Grant date | Sep 25, 2001 |
| Priority date | — |
| Expiry date | Jun 8, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/94
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In order to prevent accumulation of rounding errors caused by the integer-based bilinear interpolation used in the motion compensation process of image coding and decoding methods, two types of P frames are used for unidirectional motion compensation prediction: P+ frames, which round the results of bilinear interpolation with real number operations to the nearest integer and round half integer values (0.5 added to an integer) away from zero; and P- frames, which differ from P+ frames in that the above mentioned half integer values are rounded towards zero. Utilizing both of these P+ and P- frames enables canceling of rounding errors and prevents the accumulation of rounding errors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.