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:
Nov. 12, 1996
Filed:
Oct. 12, 1995
Takahiro Hamada, Saitama, JP;
Shuichi Matsumoto, Tokyo, JP;
Abstract
A sync controller 14 controls an amount of delay of a delay part 15 so that original video data entered from a video source 1 is synchronized with reproduced video data which is compressed and reproduced by a system to be evaluated. A first OT calculator 17 orthogonally transforms a reproduced image, a second OT calculator 21 orthogonally transforms an original image and a subtractor 19 obtains a difference value of the same order coefficients in one block. A WSNR calculator 22 weights the difference with a weighting function which varies with a position of a coefficient of orthogonally transformed data and a magnitude of an AC power in the block after orthogonal transform of the original image and subsequently obtains an average weighted S/N ratio of each video frame or a plurality of video frames. Finally, a subjective evaluation value calculator 23 calculates a subjective evaluation value (deterioration percentage) according to the average weighted S/N ratio. Consequently, the present invention enables to provide a video quality evaluating equipment for a reproduced image of a video signal subject to digital compression capable of economically evaluating the video quality in a short period of time.