Apparatus and method for processing an input audio signal using cascaded filterbanks

US11495236B2 · kind B2 · utility

Assignees

• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE
• Dolby International AB · IE

Inventors

• Lars Villemoes · Stockholm, SE
• Per Ekstrand · Saltsjöbaden, SE
• Sascha Disch · Bad Mergentheim, DE
• Frederik Nagel · Nuremberg, DE
• Stephan Wilde · Wendelstein, DE

Key dates

• Filing date: May 19, 2020
• Grant date: Nov 8, 2022
• Expiry date: Jul 31, 2040

Classification

• Technology area (CPC G): Physics
• CPC primary: G10L21/04
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

An apparatus for processing an input audio signal relies on a cascade of filterbanks, the cascade having a synthesis filterbank for synthesizing an audio intermediate signal from the input audio signal, the input audio signal being represented by a plurality of first subband signals generated by an analysis filterbank, wherein a number of filterbank channels of the synthesis filterbank is smaller than a number of channels of the analysis filterbank. The apparatus furthermore has a further analysis filterbank for generating a plurality of second subband signals from the audio intermediate signal, wherein the further analysis filterbank has a number of channels being different from the number of channels of the synthesis filterbank, so that a sampling rate of a subband signal of the plurality of second subband signals is different from a sampling rate of a first subband signal of the plurality of first subband signals.