Multiple description transform coding of images using optimal transforms of arbitrary dimension
US6330370A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1998 |
| Grant date | Dec 11, 2001 |
| Priority date | — |
| Expiry date | Sep 30, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04S1/00
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A multiple description (MD) joint source-channel (JSC) encoder in accordance with the invention encodes n components of an image signal for transmission over m channels of a communication medium. In an illustrative embodiment which uses statistical redundancy between the different descriptions of the image signal, the encoder forms vectors from transform coefficients of the image signal separated both in frequency and in space. The vectors may be formed such that the spatial separation between the transform coefficients is maximized. A correlating transform is then applied, followed by entropy coding, grouping as a function of frequency, and application of a cascade transform. In an illustrative embodiment which uses deterministic redundancy between the different descriptions of the image signal, the encoder may apply a linear transform, followed by quantization, to generate the multiple descriptions of the image signal. For example, vectors may be formed from transform coefficients of the image signal so as to include coefficients of like frequency separated in space. The vectors are expanded by multiplication with a frame operator, and then quantized using a step size which may b…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.