Device and method for CD shuffle play
US5408448A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 8, 1993 |
| Grant date | Apr 18, 1995 |
| Priority date | — |
| Expiry date | Oct 8, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/913
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Varying the selection and play of tracks on a CD in non-sequential order includes a CD mechanism (12) with which a processor (16) communicates, a keyboard (17) having a shuffle play key (18) for user actuation, and a disc and track display (19). The processor (16) generates a shuffled selection offset (T.sub.n) from a deterministic function based upon a sequence number (S.sub.n) and a random seed (Seed). The deterministic function includes performance of plurality of binary operations which may include bit inversions, exclusive OR with an N-bit constant, N-bit rotations, bit swapping, one to one substitutions, and modulus additions and subtractions. The generated sequence plays all selections before any selection is repeated, allows the user to replay any past selection or skip to any unplayed selection while maintaining the same order, requires minimal memory and execution time, and is suitable for use with single-disc CD players and multi-disc CD changers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.