Method for the sequential transmission of compressed video information at varying data rates
US5903775A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 6, 1996 |
| Grant date | May 11, 1999 |
| Priority date | — |
| Expiry date | Jun 6, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N7/24
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method is provided for allowing the transmission of digital video segments along a number of transmission channels, with the line speed, or rate of transmission in bits per second, being variable during a transmission. For each transmission channel, video data segments are stored in a data buffer, along with data segments known as Write Control Blocks (WCBs). Each WCB includes a pointer to the video data segment with which it is associated and a line speed code indicating the preferred rate of data transmission. The addresses of the WCBs are stored in a FIFO buffer which is established for each transmission channel. When coded information within a WCB indicates that a speed change is needed, a run-time subroutine executing in a co-processor sets bits within a channel control word forming a portion of each WCB to stop a DMA process and to issue an interrupt when the corresponding video segment is to be transmitted. An interrupt handler determines the new line speed and sets a variable speed clock accordingly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.