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:
Jun. 20, 1995
Filed:
Dec. 31, 1992
Ronald R Bocox, Nobel, CA;
Lloyd L Lautzenhiser, Nobel, CA;
Emhiser Research Limited, Parry Sound, CA;
Abstract
A method for inserting an audio signal (132) into a composite video signal (10) having a front porch (24), a back porch (26 or 32), a horizontal sync pulse (20) with a leading edge (22), and a luminance portion (16) to provide an audio-on-video signal (222), includes removing one or more video parts (180, 200) at least partially from the luminance portion (16), sampling one or more audio parts (182, 202), biasing a zero magnitude (238) of the audio parts (182, 202) to the midpoint (240) of the maximum luminance magnitude (242), and placing the sampled parts (182, 202) at least partially within the luminance portion (16) of the composite video signal (10) to form the audio-on-video signal (222). The method for inserting also includes inserting audio parts (212) into blanking parts (206) that follow leading and trailing equalizing pulses (46, 56); and the method for inserting further includes inserting audio parts ( 214) into blanking portions (60) of test signals (58) that follow the trailing equalizing pulses (56). A method for separating an audio signal (132) from the audio-on-video signal (222) includes sampling an audio plus magnitude (230) of the audio parts (182 and/or 202) at least partially within the luminance portion (16), subtracting a bias magnitude (234) to provide an audio sample magnitude (280 or 288), holding the audio ample magnitude (280 or 288), replacing the held audio sample magnitude (20 or 288) with a successive audio sample magnitude (280 or 288) to provide a stepped audio output (320), low pass filtering (310) to smooth the stepped audio output (320) and to prevent Nyquist problems, and high pass filtering (310) to prevent noise when an audio sample magnitude (318) is held during a vertical sync pulse (48).
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile