Systems and Methods of Performing Noise Modulation and Gain Adjustment

A method comprising:

• determining a first set of spectral frequency values corresponding to an audio signal;
• determining a second set of spectral frequency values that approximates the first set of spectral frequency values;
• and
• adjusting a gain value corresponding to at least a portion of the audio signal based on a difference between the first set and the second set.

An apparatus comprising:

• a filter configured to generate a third value of a mixing factor at least partially based on a first value of the mixing factor and a second value of the mixing factor, wherein the first value corresponds to a first portion of an audio signal and wherein the second value corresponds to a second portion of the audio signal;
• and
• a mixer configured to receive the third value and to generate a high-band excitation signal corresponding to a high-band portion of the audio signal by generating modulated noise and combining the modulated noise and a transformed version of a low-band excitation signal, the low-band excitation signal corresponding to a low-band portion of the audio signal,
• wherein the mixer is configured to combine the modulated noise and the transformed version of the low-band excitation signal based on the third value.

An apparatus comprising:

• means for generating a third value of a mixing factor at least partially based on a first value of the mixing factor and a second value of the mixing factor, wherein the first value corresponds to a first portion of an audio signal received at an audio encoder and wherein the second value corresponds to a second portion of the audio signal;
• and
• means for generating a high-band excitation signal corresponding to a high-band portion of the audio signal by combining modulated noise and a transformed version of a low-band excitation signal, the low-band excitation signal corresponding to a low-band portion of the audio signal,
• wherein the means for generating is configured to combine the modulated noise and the transformed version of the low-band excitation signal based on the third value.

A non-transitory computer-readable medium comprising instructions that, when executed by a computer, cause the computer to:

• receive a first value of a mixing factor, the first value corresponding to a first portion of an audio signal received at an audio encoder;
• receive a second value of the mixing factor, the second value corresponding to a second portion of the audio signal;
• generate a third value of the mixing factor at least partially based on the first value and the second value;
• and
• mix an excitation signal with modulated noise based on the third value of the mixing factor.

An apparatus comprising:

• an analysis filter configured to determine a first set of spectral frequency values corresponding to an audio signal;
• a quantizer configured to generate a second set of spectral frequency values that approximates the first set of spectral frequency values;
• and
• a gain circuit configured to adjust a gain value corresponding to at least a portion of the audio signal based on a difference between the first set and the second set.

An apparatus comprising:

• means for determining a first set of spectral frequency values corresponding to an audio signal;
• means for generating a second set of spectral frequency values that approximates the first set of spectral frequency values;
• and
• means for adjusting a gain value corresponding to at least a portion of the audio signal based on a difference between the first set and the second set.

A non-transitory computer-readable medium comprising instructions that, when executed by the computer, cause the computer to:

• determine a first set of spectral frequency values corresponding to an audio signal;
• determine a second set of spectral frequency values that approximates the first set of spectral frequency values;
• and
• adjust a gain value corresponding to at least a portion of the audio signal based on a difference between the first set and the second set.