Video data recording and reproducing apparatus, a video data reproducing apparatus, and a method of recording and reproducing video data with data modification detection
US6807365B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | May 24, 2000 |
| Grant date | Oct 19, 2004 |
| Priority date | — |
| Expiry date | May 24, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2020/1843
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
First modification detection data is generated from the (compressed) video data. The video data is combined with the first modification detection data. The combined data is recorded on a recording medium. The read combined data is separated into the compressed video data and the first modification detection data. Second modification detection data is generated according to the separated compressed data. The separated first data modification detection data is compared with the second data modification detection data to detect data modification. Outputting expanded video data is controlled according to the comparing result. The recorded data may be copied on a removable disc. A data reproducing apparatus having the second modification detection data generation circuit and the comparing circuit reproduces the removable disc. The reproduced video data may be further processed by a watermark processing circuit to embed watermark data in the video data which are recorded on another removable disc. The compressed video data may be transmitted through a network with encrypting. Encrypting key data is exchanged between the data transmitting side and the receiving side for decrypting. Encryp…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.