Decoder for digital signal codes
US4821290A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 26, 1988 |
| Grant date | Apr 11, 1989 |
| Priority date | — |
| Expiry date | Aug 26, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/50
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A binary tree search system locates and outputs video data stored in a ROM, the data corresponding to received variable length uniquely encoded codewords. The data for each codeword is stored at a unique ROM address, each address corresponding to a tree leaf. Certain ROM locations not associated with complete codewords include a partial search address for the next search node, the remainder of the search address for each node comprising a bit of the serial received encoded data. When the received bits complete a codeword, the last received bit and the prior accessed ROM stored partial address form a pointer address to a tree leaf that accesses that ROM location containing the data corresponding to that codeword. Flags are generated by each accessed location to indicate whether or not a codeword has been found. If a codeword is found, the search is restarted at the tree root.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.