Hybrid video compression/decompression system
US6195391A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 1994 |
| Grant date | Feb 27, 2001 |
| Priority date | — |
| Expiry date | May 31, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/00
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A digitized image compression system employs several different compression techniques to compress the luminance and chrominance information and encodes the selected technique "on the fly" by inserting selected escape and header codes into the encoded data stream. More particularly, during compression, each image is divided into non-overlapping contiguous regions, referred to hereinafter as blocks and image data is compressed on a block-by-block basis. Each encoded block begins with a one-byte header that indicates, in conjunction with a previous escape code, the compression technique which was used to encode the block. Therefore, interpretation of the encoded data is a hierarchical process: the escape codes indicate a stream interpretation mode which, in turn, determine the meaning of header values which follow and the header values, in turn, determine the meaning of the encoded data in each block. The majority of image blocks are divided into quadrants and each block header is arranged as a sequence of four two-bit codes which indicate the encoding used for the four quadrants within the associated block. However, certain combinations of encoding that are unlikely to occur within t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.