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. 06, 2001
Filed:
Jul. 21, 1998
Konstantinos Konstantinides, SanJose, CA (US);
Daniel R. Tretter, Mountian View, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
An image compression system for compound images containing both text and pictures. The system is capable of receiving the images on a non-overlapping 8 by 8 pixel blank basis and includes a discrete cosine transformer connected to a quantizer drawing lossy quantization factors from quantization tables. The lossy quantization factors are modified by a variable quantization subsystem based on the frequency of changes in the block to provide low lossy quantization factors for high frequency of changes and high lossy quantization factors for low frequency of changes. The high frequency of changes being indicative of text and the low frequency of changes being indicative of pictures. The quantizer is connected to an entropy coder using lossless entropy encoding factors from Huffman tables to provide JPEG compliant files.