PCM Recording and reproducing method providing for dropout compensation
US4224642A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 11, 1978 |
| Grant date | Sep 23, 1980 |
| Priority date | — |
| Expiry date | May 11, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/1809
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
For recording and reproducing analog audio signals by a pulse-code modulation scheme so as to permit effective compensation for dropout errors, an incoming audio signal is sampled, and the analog samples are converted into a sequence of coded pulse groups or words. These words are grouped into successive notional blocks, and the odd and the even words, for example, of each block are divided into sub-blocks, as by sequentially writing the words of each block in successive storage locations in a memory and by retrieving the odd, and then the even, words from the memory. The sub-blocks of the successive word blocks are recorded in different regions on a recording medium such as magnetic tape. After being reconverted into an electrical signal from the recording medium, the words of the sub-blocks of each block are rearranged into the original order, as by use of a second memory, prior to the reconstruction of the analog audio signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.