The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 08, 1991
Filed:
Nov. 01, 1990
Ronald J Lisle, Cedar Park, TX (US);
B Scott McDonald, Leander, TX (US);
Michael D Wilkes, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method and apparatus are disclosed for simultaneously outputting digital audio and MIDI synthesized music utilizing a single digital signal processor. The Musical Instrument Digital Interface (MIDI) permits music to be recorded and/or synthesized utilizing a data file containing multiple serially listed program status messages and matching note on and note off messages. In contrast, digital audio is generally merely compressed, utilizing a suitable data compression technique, and recorded. The audio content of such a digital recording may then be restored by decompressing the recorded data and converting that data utilizing a digital-to-analog convertor. The method and apparatus of the present invention selectively and alternatively couples portions of a compressed digital audio file and a MIDI file to a single digital signal processor which alternately decompresses the digital audio file and implements a MIDI synthesizer. Decompressed audio and MIDI synthesized music are then alternately coupled to two separate buffers. The contents of these buffers are then additively mixed and coupled through a digital-to-analog convertor to an audio output device to create an output having concurrent digital audio and MIDI synthesized music.