Noise reduction devices and noise reduction methods
AssigneeIntel Deutschland GmbH
InventorNavin Chatlani
Life of this patent
Estimating the term…
Abstract
A noise reduction device may be provided. The noise reduction device may include: an input configured to receive an input signal including a representation in a frequency domain of an audio signal, wherein the representation includes a plurality of time frames and a plurality of coefficients for each time frame; a noise detection circuit configured to determine a first indicator being indicative of a bandwidth of a coefficient over at least two time; a noise reduction circuit configured to reduce based on the first indicator a noise component in the audio signal; and an output configured to output an output signal including a representation in the frequency domain of the audio signal with the reduced noise component.
Claims13
A noise reduction device configured for use in a radio communication device comprising:
- an input configured to receive an audio signal comprising a representation having a plurality of power envelopes;
- wherein the audio signal consists of a noise-free speech component and a tonal noise component;
- a tonal noise detection circuit configured to estimate a tonal noise probability based on a first indicator and a second indicator;
- wherein the first indicator represents an amount of the tonal noise component in the audio signal based on a magnitude of difference between a maximum power envelope and a minimum power envelope;
- wherein the second indicator represents a ratio of the largest spectral peak within a frequency range between 501 Hz to 1 KHz as compared to the largest spectral peak within a frequency range between 0 Hz to 500 Hz;
- memory for storing the first indicator and a predetermined range for the first indicator and for storing the second indicator and a predetermined threshold for the second indicator;
- a noise reduction circuit configured to reduce the tonal noise component within the audio signal when the first indicator is outside the predetermined range for the first indicator and when the second indicator is above the predetermined threshold;
- and
- an output configured as an audio signal comprising a reduced amount of the tonal noise component.
A radio communication device implemented method for decreasing tonal noise in an audio signal, wherein the method comprises:
- receiving an audio signal comprising a plurality of power envelopes;
- wherein the audio signal consists of a noise-free speech component and a tonal noise component;
- estimating a tonal noise probability based on a first indicator and a second indicator with a tonal noise detection circuit;
- wherein the first indicator represents an amount of the tonal noise component in the audio signal based on a magnitude of difference between a maximum power envelope and a minimum power envelope;
- and wherein the second indicator represents a ratio of the largest spectral peak within a frequency range between 501 Hz to 1 KHz as compared to the largest spectral peak within a frequency range between 0 Hz to 500 Hz;
- storing the first indicator and a predetermined range for the first indicator in a memory location and storing the second indicator and a predetermined threshold for the second indicator;
- comparing the first indicator to the predetermined range for the first indicator and comparing the second indicator to the predetermined threshold;
- reducing the tonal noise component within the audio signal when the first indicator is outside the predetermined range for the first indicator and when the second indicator is above the predetermined threshold;
- and
- outputting an audio signal comprising a reduced amount of the tonal noise component.
A noise reduction device for use in a radio communication device selected from the group consisting of a mobile telephone, a personal digital assistant, a mobile computer, and combinations thereof;
- wherein the noise reduction device comprises:
- an input configured to receive an audio signal comprising a representation having a plurality of power envelopes;
- wherein the audio signal consists of a noise-free speech component and a tonal noise component;
- a tonal noise detection circuit configured to estimate a tonal noise probability based on a first indicator and a second indicator;
- wherein the first indicator represents an amount of the tonal noise component in the audio signal based on a magnitude of difference between a maximum power envelope and a minimum power envelope;
- and wherein the second indicator represents a ratio of the largest spectral peak within a frequency range between 501 Hz to 1 KHz to as compared to the largest spectral peak within a frequency range between 0 Hz to 500 Hz;
- memory for storing the first indicator, a predetermined range for the first indicator, and storing the second indicator and a predetermined threshold for the second indicator;
- a noise reduction circuit configured to reduce the tonal noise component within the audio signal when the first indicator is outside the predetermined range for the first indicator and when the second indicator is above the predetermined threshold;
- and
- an output configured as an audio signal comprising a reduced amount of the tonal noise component.
Dependencies are inferred from the claim text.