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:
Jan. 21, 2003
Filed:
Apr. 27, 2000
Hiroyuki Ishikawa, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A moving picture coding apparatus is provided which is capable of controlling a bit rate of output codes so as not to exceed a target bit rate and reducing noises in a decoded image. The apparatus comprises: a converter for converting prediction errors of a plurality of pixel data into frequency components on a block basis; a quantizer for quantizing converted prediction errors with reference to a quantization table; a dequantizer for dequantizing quantized prediction errors with reference to a quantization table; a coder for coding the quantized prediction errors to generate codes; an output buffer for buffering the codes; a buffer checker for checking a code occupied ratio in the output buffer; a plurality of quantization tables; and a quantization table selector for selecting on quantization table from the plurality of quantization tables in accordance with the code occupied ratio. The quantizer employs the selected on quantization table, and the dequantizer employs a quantization table determined for a group of pictures.