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. 14, 1983
Filed:
Jun. 30, 1978
Paul A Spencer, London, GB;
Ray M Dolby, London, GB;
Dolby Laboratories, Inc., San Francisco, CA (US);
Abstract
Noise reduction of a signal such as a video signal is effected by averaging a plurality of relatively delayed replica signals, e.g. with line or field delays therebetween, in a decoding processor, the highly redundant information content of the signal being reinforced by the averaging while random noise undergoes a partial cancellation. In order to overcome the problem of signal changes caused by the decoding processor, the signal is encoded prior to application to the noise-introducing signal channel by a complementary encoding processor in which one or more replica signals are subtractively combined with one or more other replica signals. In both processors a variable combining means is employed to exclude from the combination replica signals which have a non-small difference from the replica signals in the combination, thereby to avoid smearing of the information content (with consequent picture smearing in the case of a video signal) when the signal is changing, e.g. because of movement in a picture.