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. 28, 1993
Filed:
May. 11, 1992
Christopher H Strolle, Glenside, PA (US);
Raymond A Schnitzler, Highland Park, NJ (US);
SamSung Electronics Co. Ltd., Suwon, KR;
Abstract
A television signal having a luminance spectrum extending from zero to f.sub.h in horizontal spatial frequencies and from zero to f.sub.v in vertical spatial frequencies is recorded on a video tape. A folded-spectrum signal is generated for recording by modulating the luminance signal onto a folding carrier of (f.sub.h /2, f.sub.v /2) complex spatial frequency. This is done by heterodyning the luminance signal with a folding carrier wave and then selecting as said folded-spectrum signal only the baseband portion of the resulting signal. At least when there is change between successive television images, the luminance signal is pre-filtered by a low-pass spatial filter that separates the two-dimensional image spectral domain into a pass band region and into an attenuation band region. Each point in the passed region has a corresponding mirror point in the attenuated region as mirrored about a complex spatial frequency (f.sub.h /4, f.sub.v /4) in both horizontal and vertical directions. During subsequent playback the folded-spectrum signal recovered from the tape is unfolded by heterodyning it with the folding carrier wave and selecting only the baseband portion of the resulting signal. At least when there is change between successive television images, the unfolded-spectrum signal is passed through a low-pass spatial reconstruction filter similar to that used as a recording pre-filter, and accompanying aliases are attenuated by the reconstruction filter.