Data communication control apparatus and its control method, image processing apparatus and its method, and data communication system
US6744927B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 22, 1999 |
| Grant date | Jun 1, 2004 |
| Priority date | — |
| Expiry date | Dec 22, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/18
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In video conference system terminals, the conventional difficulty in high-quality display of facial expressions of a plurality of participants is solved. In a multipoint connection device connecting a plurality of video conference terminals, image data transmitted from a terminal is decoded, and a face area in the image data is recognized. Then, quantization coefficients for the face area are set to be greater coefficients than those for other areas than the face area, then the image data is compressed, and delivered to the respective terminals. By this arrangement, in image data, a face area with great significance can be re-compressed without degradation of image quality, while an area with less significance such as background can be compressed with high efficiency. Thus, the total code amount can be reduced. Accordingly, even if the system uses a narrow band communication channel, the significant face area can be clearly displayed at the respective terminals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.