Enhancing artificial reverberation in a noisy environment via noise-dependent compression
A system for enhancing artificial reverberation in a noisy listening space includes a sensor configured to generate a signal indicating a current noise level in a listening space, a loudspeaker configured to output sound in the listening space based on an output signal, and at least one processor. The at least one processor is configured to execute instructions to: generate an artificial reverberation signal based on a source signal and a response of a listening space, wherein the artificial reverberation signal includes a first low output-level portion having output levels that are below a compression threshold level and a first high output-level portion having output levels that are above the compression threshold level; generate a compressed artificial reverberation signal based on the artificial reverberation signal by increasing the output levels of the low output-level portion by a first magnitude and increasing the output levels of the high output-level portion by less than the first magnitude; and combine the compressed artificial reverberation signal with the source signal to form an output signal for the listening space.
1. A method of signal compression, the method comprising:
generating an artificial reverberation signal based on a source signal and a response of a listening space, wherein the artificial reverberation signal includes a first low output-level portion having output levels that are below a compression threshold level and a first high output-level portion having output levels that are above the compression threshold level;
generating a compressed artificial reverberation signal by increasing the output levels of the first low output-level portion by a first magnitude and increasing the output levels of the first high output-level portion by less than the first magnitude; and
combining the compressed artificial reverberation signal with the source signal to form an output signal for the listening space.
2. The method of claim 1 , further comprising:
based on a current noise level associated with the listening space, determining a target value for the compression threshold level; and
changing a current value for the compression threshold level to the target value.
3. The method of claim 2 , further comprising determining the current noise level based on a signal from a microphone disposed in the listening space.
4. The method of claim 2 , further comprising determining the current noise level based on a current speed of a vehicle in which the listening space is disposed.
5. The method of claim 2 , further comprising determining the current noise level based on a current state of a device that generates noise within the listening space.
6. The method of claim 5 , wherein the listening space is disposed within a vehicle.
7. The method of claim 1 , further comprising:
based on a current noise level associated with the listening space, determining a target value for a compression parameter for generating the compressed artificial reverberation signal; and
changing a current value for the compression parameter to the target value.
8. The method of claim 1 , wherein generating the compressed artificial reverberation signal comprises modifying the artificial reverberation signal with an upward compression scheme.
9. The method of claim 8 , wherein modifying the artificial reverberation signal with an upward compression scheme comprises:
generating the output levels of a second low output-level portion based on the output levels of the first low output-level portion; and
setting the output levels of a second high output-level portion equal to the output levels of the first high output level portion.
10. The method of claim 8 , wherein modifying the artificial reverberation signal with an upward compression scheme comprises generating the output levels of the second low output-level portion based on increasing the output levels of the first low output-level portion by a ratio of the upward compression scheme.
11. A system, comprising:
a sensor configured to generate a signal indicating a current noise level in a listening space;
a loudspeaker configured to output sound in the listening space based on an output signal; and
at least one processor configured to execute instructions to:
generate an artificial reverberation signal based on a source signal and a response of the listening space, wherein the artificial reverberation signal includes a first low output-level portion having output levels that are below a compression threshold level and a first high output-level portion having output levels that are above the compression threshold level;
generate a compressed artificial reverberation signal based on the artificial reverberation signal by increasing the output levels of the first low output-level portion by a first magnitude and increasing the output levels of the first high output-level portion by less than the first magnitude; and
combine the compressed artificial reverberation signal with the source signal to form an output signal for the listening space.
12. The system of claim 11 , wherein generating the compressed artificial reverberation signal comprises modifying the artificial reverberation signal with a parallel compression scheme.
13. The system of claim 12 , wherein modifying the artificial reverberation signal with the parallel compression scheme comprises:
generating a treated artificial reverberation signal by compressing the artificial reverberation signal with a downward compression scheme; and
generating a parallel-compressed artificial reverberation signal by summing the treated artificial reverberation signal with the artificial reverberation signal.
14. The system of claim 11 , further comprising:
based on a current noise level associated with the listening space, determining a target value for the compression threshold level; and
changing a current value for the compression threshold level to the target value.
15. The system of claim 14 , further comprising determining the current noise level based on a signal from a microphone disposed in the listening space.
16. The system of claim 14 , further comprising determining the current noise level based on a current speed of a vehicle in which the listening space is disposed.
17. The system of claim 14 , further comprising determining the current noise level based on a current state of a device that generates noise within the listening space.
18. The system of claim 17 , wherein the listening space is disposed within a vehicle.
19. A non-transitory computer-readable storage medium including instructions that, when executed by at least one processor, configure the at least one processor to perform the steps of:
generating an artificial reverberation signal based on a source signal and a response of a listening space, wherein the artificial reverberation signal includes a first low output-level portion having output levels that are below a compression threshold level and a first high output-level portion having output levels that are above the compression threshold level;
generating a compressed artificial reverberation signal by increasing the output levels of the first low output-level portion by a first magnitude and increasing the output levels of the first high output-level portion by less than the first magnitude; and
combining the compressed artificial reverberation signal with the source signal to form an output signal for the listening space.
20. The non-transitory computer-readable storage medium of claim 19 , further including instructions that, when executed by at least one processor, configure the at least one processor to perform the steps of:
based on a current noise level associated with the listening space, determining a target value for the compression threshold level; and
changing a current value for the compression threshold level to the target value.