Method for communicating audiovisual programs over a communications network
US5874986A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 26, 1996 |
| Grant date | Feb 23, 1999 |
| Priority date | — |
| Expiry date | Jun 26, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/8586
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Audiovisual programs are transmitted over a low-bandwidth network in a compressed form in which the number of video frames has been reduced by selecting "significant" frames. The user sees a series of still images accompanying an apparently full audio channel. The frames are downloaded to the user in an order designed to assure, first, that the next few frames necessary for viewing are present, but also so that the user can scroll throughout the program even as it is being downloaded. This is accomplished by first downloading the full audio for the program portion requested by the user's viewer software, and then downloading the video frames based on requests from the viewer software, which has access to a table indicating which video frames are associated with which audio portions. The software uses the table to download frames needed immediately, as well as to download advance frames based on their significance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.