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. 04, 1991
Filed:
Jun. 13, 1990
Northern Telecom Limited, Montreal, CA;
Abstract
Digital samples of an HDTV video signal are compressed by determining groups each of three successive samples in the video signal lines, the groups in adjacent lines being offset from one another, and transmitting only a first sample in each group. Each of the second and third samples in each group is compared with magnitudes averaged from three adjacent, transmitted, first samples, one in each of the previous, same, and following video signal lines, to determine a closest match. A 2-bit code representing this closest match is transmitted for each of these second and third samples in each group. The groups, and hence the first samples, are offset from one another in adjacent video signal lines, and the sampling frequency is desirably an odd multiple of half the video signal line frequency to offset the sampled pixels in adjacent video signal lines. The invention provides a high compression ratio, which can be further increased by DPCM encoding of the successive first samples.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile