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:
Oct. 19, 2004
Filed:
Jan. 17, 2003
Charles K. Chui, Menlo Park, CA (US);
Hong-Ye Gao, Milpitas, CA (US);
Lefan Zhong, Santa Clara, CA (US);
Zoran Corporation, Sunnyvale, CA (US);
Abstract
An image is divided into nonoverlapping tiles, and the tiles are processed in a predefined order. Each tile is processed by applying a predefined family of transform layers to the tile so as to generate successive sets of transform coefficients. The sets of transform coefficients correspond to spatial frequency subbands of the image. The subbands are grouped in accordance with the transform layer that generated them. For one or more respective groups of subbands one or more parameters are generated whose value is indicative of the density of image features in the tile. The tile is classified in accordance with the values of the one or more parameters. Based on the classification, a set of quantization factors for the tile are selected, and then the transform coefficients of the tile are scaled by the selected set of quantization factors to as to generate a set of quantized transform coefficients.