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:
Aug. 17, 1993
Filed:
Nov. 29, 1991
Ikuo Inoue, Yokohama, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A video signal encoding apparatus of the type in which inter-frame difference values for respective picture elements are subjected to orthogonal transform processing and the resultant transform coefficients are quantized and encoded, with respective values of quantization step size applied to successive 2-dimensional blocks of picture element values being varied such as to control the encoded data bit stream to a constant bit rate, in which the quantization step size for each block is also controlled in accordance with whether or not the block lies on a border between a visually smooth region of the picture expressed by the video signal and a region in which substantial changes occur in the picture. The step size can thereby be set to be sufficiently small, in the case of specific blocks for which is necessary to use a small size of quantization step in order to prevent noise from appearing in the picture obtained from the decoded video signal.