Methods and systems for start code emulation prevention and data stuffing
US7839895B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 2009 |
| Grant date | Nov 23, 2010 |
| Priority date | — |
| Expiry date | May 14, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04J3/0605
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Methods and systems provide approaches to start code emulation prevention at a granularity higher than the bit level. By operating at a level other than the bit level, processing capability requirements on both the encoder and decoder side can be reduced. In accordance with one or more embodiments, a start code emulation prevention method looks for data patterns relative to fixed-size data portions larger than single bits. When a particular pattern is found, start code emulation prevention data is inserted to prevent start code emulation. The inserted data is larger than a single bit and, in some embodiments, comprises a byte. When a decoder decodes data that has had start code emulation prevention data inserted, it can easily identify legitimate start codes and then can remove the start code emulation prevention data to provide the original data that was protected. In addition, a data stuffing method is described which allows payload data to be rounded up in size to an integer number of byte sizes, and then allows filler data to be added in a manner which is easily detectable by a decoder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.