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:
Dec. 12, 2000
Filed:
Oct. 21, 1998
Tiernan Communications, Inc., San Diego, CA (US);
Abstract
A luminance notch filter for preventing color crosstalk adaptively attenuates a SECAM luminance signal depending on the strength of the luminance signal using digital filtering techniques. The adaptive luminance notch filter includes a bandpass filter centered at the chrominance band that is operative to receive the input luminance signal and provide a bandpass filtered luminance signal. The bandpass filtered luminance signal is multiplied by a gain factor and the multiplied luminance signal is subtracted from the input luminancee signal to provide a notch filtered luminance signal. A detector coupled to the bandpass filter output detects the signal strength of the bandpass filtered luminance signal and the gain factor is adapted in accordance with the detected signal strength. The bandpass filter comprises an infinite impulse response (IIR) filter that is preferably an all-pole IIR filter of at least 3.sup.rd order.