System and method for scalable portrait video
US7479957B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 25, 2005 |
| Grant date | Jan 20, 2009 |
| Priority date | — |
| Expiry date | Dec 30, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/6131
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Generation, coding and transmission of an effective video form, scalable portrait video. As an expansion to bi-level video, portrait video is composed of more gray levels, and therefore possesses higher visual quality while it maintains a low bit rate and low computational costs. Portrait video is a scalable video in that each video with a higher level always contains all the information of the video with a lower level. The bandwidths of 2-4 level portrait videos fit into the bandwidth range of 20-40 Kbps that GPRS and CDMA 1X can stably provide. Therefore, portrait video is very promising for video broadcast and communication on 2.5 G wireless networks. With portrait video technology, this system and method is the first to enable two-way video conferencing on Pocket PCs and Handheld PCs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.