Controlling quantization parameters based on code amount
US5861921A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1994 |
| Grant date | Jan 19, 1999 |
| Priority date | — |
| Expiry date | Mar 28, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/146
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
There is provided code amount control in which information data are input in predetermined units and a code amount is estimated in each of a plurality of stages, including a final stage. A calculation result is obtained based on a target code amount and the estimated code amount, for each stage. A short code amount and an excess code amount are updated based on the calculation result, and quantization parameters used upon encoding are controlled in accordance with the short code amount and the excess code amount obtained at the final estimation stage. Also provided is code amount control for controlling a code amount in units of second blocks, each consisting of a plurality of first blocks, each consisting of a plurality of sample value data, which discriminates quantization parameters which result in a code amount less than a predetermined amount when a second block of data is encoded using the quantization parameters. The discriminated quantization parameters are adjusted on a unit basis of the first block.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.