Adding data to a compressed data frame
US6807528B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 8, 2001 |
| Grant date | Oct 19, 2004 |
| Priority date | — |
| Expiry date | Mar 12, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L19/002
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Many low bit rate digital audio encoding systems, including Dolby Digital and MPEG-2 AAC generate data streams in which unused dummy, fill, stuffing, or null bits exist whenever the bit allocation function in the encoder does not utilize all available bits from a bit pool. Instead, all or some of such wasted bits are used to carry information. This can be accomplished after an encoder generates a bitstream. The resulting bitstream is analyzed to identify the locations of some or all of the unused bits. Some or all of the identified unused bits are then replaced with information-carrying bits to embed information-carrying bits in locations formerly occupied by unused bits. Alternatively, instead of replacing some or all unused bits in the bitstream with information-carrying bits after encoding, a modified encoder may insert information-carrying bits in some or all of the unused bit positions during the encoding process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.