System for encoding sound recordings for high-density storage and

Abstract

Method and apparatus for addressably writing digital representations of high-fidelity sound recordings in a non-mapped digital storage device, such as a CD music ROM, using conventional PCM (pulse code modulated) equipment, but in a more condensed and efficiently sampled ADM (adaptive delta modulated) format thereby providing high-density addressable storage of several thousand recordings in a single music ROM jukebox as well as high-speed information transfers. The invention enables communication and control links between conventional digital audio processors and conventional microcomputers. Timing data is embedded in the ADM formatted and blocked data file. The microcomputer is utilized for editing ADM data, inserting catalog data, and transferring the data file to a standard PCM file writer suitable for making non-mapped CD music ROMs containing addressable ADM data files on conventional equipment utilized in the indstry. Encoding is performed by Dolby delta-link ADM encoding to achieve time-domain condensation of information content, and analog signals representing the sound recording are peak-limited prior to preprocessing by Dolby B noise reduction techniques. CD music ROMs produced thereby are utilized in high-speed reproduction systems or for addressable computer access in high-volume archival storage systems.