Method and apparatus for coding moving picture at variable bit rate
US6763138B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 9, 2000 |
| Grant date | Jul 13, 2004 |
| Priority date | — |
| Expiry date | Mar 9, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/61
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
To provide a picture coding method and apparatus capable of achieving a high image quality coding and executing a variable bit rate coding in real time. A moving picture coding means codes input moving picture data with a quantization scale Qj given from an average bit rate adjusting means. Then, the moving picture coding means outputs a code quantity Sj towards a GOP complexity computing means and an average complexity computing means. The GOP complexity is calculated on the basis of quantization scale and code quantity in the coded GOP, while the average complexity is calculated on the basis of quantization scale and code quantity from the beginning to the present. Quantization scale Qgop is calculated on the basis of the GOP complexity and the average complexity. The average bit rate adjusting means modifies Qgop and determines quantization scale Qj in accordance with an excess or shortage of Sj.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.