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:
Jul. 12, 2005
Filed:
Feb. 11, 2002
Kazutaka Naka, Yokohama, JP;
Atsushi Maruyama, Yokohama, JP;
Hiroyuki Urata, Yokohama, JP;
Masaaki Iwanaga, Yokohama, JP;
Kazutaka Naka, Yokohama, JP;
Atsushi Maruyama, Yokohama, JP;
Hiroyuki Urata, Yokohama, JP;
Masaaki Iwanaga, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a video signal processing device, an input video signal VO representing a test pattern having two gradations of black and white is converted to 8-bit data by an A/D converterin synchronism with sampling clocks generated in a write-in control circuit, and then stored in a memory. An MPUreads out picture element data in an effective area of the video signal stored in the memory, and calculates the difference AT between the average value of white-level picture element data whose values are larger than a predetermined value and the average value of black-level picture element data whose values are smaller than a predetermined value, and the total variance VT between the variance of the white-level picture element data and the variance of the black-level picture element data. The MPUcontrols the phase of the sampling clocks generated in the write-in control circuitso that the AT is maximum and the VT is minimum. With this operation, the sampling phase can be automatically adjusted to the optimum value when the video signal is converted to digital data.