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. 20, 2004
Filed:
May. 11, 1999
Jürgen Schmidt, Wunstorf, DE;
Ernst F. Schröder, Hannover, DE;
Thomson Licensing, S.A., Boulogne-Billancourt, FR;
Abstract
Generally, performing sampling-rate conversion from a higher sampling frequency fs1 to a lower sampling frequency fs results in aliasing. It is known to use a low-pass filter, known as anti-alias filter, for avoiding this alias distortion. Its effect is to remove spectral contents above fs /2 from the digital signal. According to the invention these signal parts are suppressed at spectral decoding resulting in a bandwidth of the signal to be re-sampled which is less than half of the second sampling frequency fs . This can be done for MPEG encoded audio signals by limiting the decoding to a certain number of subbands, for DOLBY AC-3 encoded audio signals by setting certain spectral lines to zero at decoding. The inventive method not only totally removes the processing power needed for calculating an anti-alias filter, but also limits the decoding work needed.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile