Apparatus, method and computer program for upmixing a downmix audio signal

US8867753B2 · kind B2 · utility

Assignee

• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE

Inventors

• Matthias Neusinger · Meiningen, DE
• Julien Robilliard · Nuremberg, DE
• Johannes Hilpert · Nuremberg, DE

Key dates

• Filing date: Jul 25, 2011
• Grant date: Oct 21, 2014
• Expiry date: Jul 23, 2032

Classification

• Technology area (CPC G): Physics
• CPC primary: G10L19/008
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

An apparatus for upmixing a downmix audio signal describing one or more downmix audio channels into an upmixed audio signal describing a plurality of upmixed audio channels includes an upmixer configured to apply temporally variable upmixing parameters to upmix the downmix audio signal in order to obtain the upmixed audio signal. The apparatus also includes a parameter interpolator, wherein the parameter interpolator is configured to obtain one or more temporally interpolated upmix parameters to be used by the upmixer on the basis of a first complex-valued upmix parameter and a subsequent second complex-valued upmix parameter. The parameter interpolator is configured to separately interpolate between a magnitude value of the first complex-valued upmix parameter and a magnitude value of the second complex-valued upmix parameter, and between a phase value of the first complex-valued upmix parameter and a phase value of the second complex-valued upmix parameter, to obtain the one or more temporally interpolated upmix parameters. A respective method can be implemented, for example, as a computer program.