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:
Dec. 23, 2003
Filed:
Nov. 29, 1999
Oliver Hartwig Werner, South Craydon, GB;
Nicholas Dominic Wells, Brighton, GB;
Michael James Knee, Petersfield, GB;
Other;
Abstract
In compression encoding of a digital signal, such as MPEG2, transform coefficients are quantised with the lower bound of each interval being controlled by a parameter &lgr;. In the MPEG2 reference coder, for example, &lgr;=0.75. Because the quantised coefficients are variable length coded, improved quality or reduced bit rates can be achieved by controlling &lgr; so as to vary dynamically the bound of each interval with respect to the associated representation level. The parameter &lgr; can vary with coefficient amplitude, with frequency, or with quantisation step size. In a transcoding operation, &lgr; can also vary with parameters in the initial coding operation.