System and method for blending multi-channel signals

Patent metadata

Field	Value
Publication number	US-9837061-B2
Application number	US-201414312031-A
Country	US
Kind code	B2
Filing date	Jun 23, 2014
Priority date	Jun 23, 2014
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

Embodiments of systems and methods for blending multi-channel signals are described. In one embodiment, a method for blending multi-channel signals involves computing component signals from the multi-channel signals, cross-fading the component signals based on different temporal rates to generate cross-faded component signals and generating a blended multi-channel signal based on the cross-faded component signals. Other embodiments are also described.

First claim

What is claimed is:

1. An article of manufacture comprises at least one non-transitory, tangible machine readable storage medium containing executable machine instructions for blending multi-channel signals, wherein execution of the program instructions by one or more processors causes the one or more processors to perform steps comprising:
computing component signals from the multi-channel signals;
cross-fading the component signals based on different temporal rates to generate cross-faded component signals; and
generating a blended multi-channel signal based on the cross-faded component signals;
wherein cross-fading the component signals based on the different temporal rates comprises:
computing a plurality of mixing factors based on the different temporal rates; and
mixing the component signals based on the mixing factors;

wherein computing the component signals from the multi-channel signals comprises computing a sum signal and a difference signal from each of the multi-channel signals;
wherein computing the mixing factors based on the different temporal rates comprises:
calculating a first mixing factor based on a first temporal rate; and
calculating a second mixing factor based on a second temporal rate such that a transition rate of the first mixing factor is faster than a transition rate of the second mixing factor; and

wherein mixing the component signals based on the mixing factors comprises:
mixing the sum signals based on the first mixing factor; and
mixing the difference signals based on the second mixing factor.

2. The article of manufacture of claim 1 , wherein computing the component signals from the multi-channel signals comprises computing the component signals such that each of the component signals is selected from the group consisting of:
a combination of a plurality of channels of the multi-channel signal;
a signal that contains a plurality of features extracted from the multi-channel signal in the time domain or in the frequency domain; and
a filtered version of the multi-channel signal.

3. The article of manufacture of claim 1 , wherein generating the blended multi-channel signal based on the cross-faded component signals comprises:
generating the blended multi-channel signal based on the sum of the cross-faded component signals and the difference between the cross-faded component signals.

4. The article of manufacture of claim 1 , wherein the blended multi-channel signal comprises a plurality of channels, wherein generating the blended multi-channel signal based on the cross-faded component signals comprises:
generating each channel of the multi-channel signal based on a combination of the cross-faded component signals.

5. The article of manufacture of claim 1 , wherein the multi-channel signals comprise two stereo audio signals.

6. The article of manufacture of claim 5 , wherein cross-fading the component signals based on the different temporal rates comprises:
generating at least one of the different temporal rates as a function of the difference between stereo components of the two stereo audio signals.

7. The article of manufacture of claim 5 , wherein the two stereo audio signals comprise a frequency modulation (FM) stereo audio signal and a Digital Audio Broadcasting (DAB) stereo audio signal that carries the same audio content as the FM stereo audio signal.

8. The article of manufacture of claim 1 , wherein the steps further comprise delaying the component signals such that the component signals are synchronized.

9. A system for blending multi-channel signals, the system comprising:
a component signals calculation unit configured to compute component signals from the multi-channel signals;
a signal cross-fading unit configured to cross-fade the component signals based on different temporal rates to generate cross-faded component signals; and
a signal processing unit configured to generate a blended multi-channel signal based on the cross-faded component signals;
wherein the signal cross-fading unit is further configured to:
compute a plurality of mixing factors based on the different temporal rates; and
mix the component signals based on the mixing factors;

wherein the component signals calculation unit is further configured to compute a sum signal and a difference signal from each of the multi-channel signals; and
wherein the signal cross-fading unit is further configured to:
calculate a first mixing factor based on a first temporal rate; and
calculate a second mixing factor based on a second temporal rate such that a transition rate of the first mixing factor is faster than a transition rate of the second mixing factor;
mix the sum signals based on the first mixing factor; and
mix the difference signals based on the second mixing factor.

10. The system of claim 9 , wherein each of the component signals is selected from the group consisting of:
a combination of a plurality of channels of the multi-channel signal;
a signal that contains a plurality of features extracted from the multi-channel signal in the time domain or in the frequency domain; and
a filtered version of the multi-channel signal.

11. A system for blending multi-channel signals, the system comprising:
a component signals calculation unit configured to compute component signals from the multi-channel signals;
a signal cross-fading unit configured to cross-fade the component signals based on different temporal rates to generate cross-faded component signals; and
a signal processing unit configured to generate a blended multi-channel signal based on the cross-faded component signals;
wherein the multi-channel signals comprise a first stereo audio signal and a second stereo audio signal that carries the same audio content as the first stereo audio signal,
wherein the component signals calculation unit is further configured to:
compute a first sum signal and a first difference signal from the first stereo audio signal; and
compute a second sum signal and a second difference signal from the second stereo audio signal,

wherein the signal cross-fading unit is further configured to:
cross-fade the first and second sum signals based on a first temporal rate to generate a cross-faded sum signal; and
cross-fade the first and second difference signals based on a second temporal rate to generate a cross-faded difference signal,
wherein the second temporal rate is different from the first temporal rate, wherein the signal processing unit is further configured to:
generate a blended stereo audio signal based on the cross-faded sum signal and the cross-faded difference signal.

Assignees

• Nxp Bv

Inventors

• Gautama Temujin

Classifications

• G10H1/18 Primary

  Selecting circuits · CPC title

• H04H40/36 Primary

  specially adapted for stereophonic broadcast receiving · CPC title

• H04H20/22

  Arrangements for broadcast of identical information via plural broadcast systems · CPC title

• G10L19/005

  Correction of errors induced by the transmission channel, if related to the coding algorithm · CPC title

• H04H20/88

  Stereophonic broadcast systems {(multiplex system in general H04J)} · CPC title