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:
Sep. 12, 1989
Filed:
Sep. 02, 1987
Keith Lucas, Oak Ridges, CA;
William F van Rassel, Willodale, CA;
Scientific Atlanta, Inc., Atlanta, GA (US);
Abstract
A method of enabling an increase in the vertical definition of a transmitted television signal while preserving its bandwidth including the steps of decimating alternate lines of the television signal and reinterpolating untransmitted alternate lines upon reception. The decimation is accomplished by diagonally filtering the television signal in two dimensions to form a figure of five sample structure. Every other line is then added to the line adjacent to it so that half the lines are available for transmission, each line comprising folded-in high frequency information about missing line samples. Prior to transmission, bnadwidth is converted by filtering the signal to be transmitted at a skew-symmetric low pass filter. Apparatus for encoding and decoding the television signal each includes a two dimensional diagonal filter and line switching and control circuitry. The storage of a full field of a sample data is not required for processing in accordance with the present method. Consequently the present apparatus comprises only line store means associated with the line switching and control circuitry of encoding apparatus.