transforms audio by applying the function f to its short-time Fourier transform.
applies the function f to the list of short-time Fourier transforms of all audioi.
Details and Options
- AudioSpectralMap can be used to arbitrarily modify the signal both in the time domain and the frequency domain. Spectral filters can be used to diminish, highlight or modify specific frequencies at specific times, e.g. removing noise.
- AudioSpectralMap applies the function f to the short-time Fourier transform and computes the inverse using the overlap-add method.
- Function f takes values of short-time Fourier transform as the first argument. Optionally, frequency and time can be given to f as the second and third arguments:
#Value or #1 value of the short-time Fourier transform #Frequency or #2 frequency in Hz #Time or #3 time in seconds
- For multichannel audio objects, the transformation is performed separately on each channel.
- When multiple audio signals are present, #Value is a list of values. Use #Value〚i〛 for audioi.
- AudioSpectralMap accepts a PartitionGranularity option that can specify the duration of each partition and the offset, as well as the smoothing window.
Examplesopen allclose all
Denoise an audio signal by eliminating all components with small amplitude:
Create a lowpass filter by removing components smaller than 1000Hz:
Zero out all the components at times smaller than 0.5 seconds:
Assign a random phase to all the components to achieve a whisper effect:
Assign a phase equal to zero to all the components to achieve a robot-like result:
Lower the amplitude of quiet components, effectively performing a simple denoise:
Completely zero out the quiet components:
Create a time-dependent highpass filter:
Denoise a signal by subtracting a noise profile:
Trim a part of the signal that contains only noise:
Compute the magnitude spectrum of the noise:
Create an interpolating function on the frequency domain using the smoothed noise spectrum:
Subtract from each component the corresponding noise spectrum magnitude:
Wolfram Research (2017), AudioSpectralMap, Wolfram Language function, https://reference.wolfram.com/language/ref/AudioSpectralMap.html.
Wolfram Language. 2017. "AudioSpectralMap." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/AudioSpectralMap.html.
Wolfram Language. (2017). AudioSpectralMap. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/AudioSpectralMap.html