Method of orthogonal transform coding/decoding
US5079547A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 1991 |
| Grant date | Jan 7, 1992 |
| Priority date | — |
| Expiry date | Feb 27, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/124
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
There is provided the method of orthogonal transform coding/decoding to quantize/de-quantize transformed coefficients which are divided into a plurality of bands to which respective different numbers of coefficient are allotted. Quantization/de-quantization tables are arranged on the basis of a probability density function of the coefficient values designed on the assumption of a specified number of coefficients so as to correspond to the number of quantization/de-quantization bits. The values in the quantization/de-quantization tables selected according to the number of quantization/de-quantization bits are adaptively compensated on the basis of an actual number of coefficients on each band to quantize/de-quantize the coefficient values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.