Apparatus for and method of transmitting video signal
US5420636A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 12, 1993 |
| Grant date | May 30, 1995 |
| Priority date | — |
| Expiry date | May 12, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/146
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The video signal containing portions locally unsuitable for coding is divided into a plurality of components and is coded by a method such as a Wavelet transform and then is transmitted. In this case, a first quantizing means controls a quantization characteristic per block consisting of small area segments of coefficients composed of respective components to make uniform a distortion within the picture and a visual obstacle caused by the distortion. A second quantizing means controls the quantization characteristic to make uniform a deterioration quantity of the entire picture within a range of a predetermined coded data quantity. It is therefore possible to effect the transmission with a stable picture quality against a variety of fluctuations in the video signal inputted.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.