AudioAnalysis Class Reference

Handles audio signal processing and feature extraction. More...

#include <audio_analysis.h>

Public Member Functions
	AudioAnalysis ()
	Constructor for the AudioAnalysis class. Initializes AudioPrism modules and other variables.
void	processAudioFrame (int)
	Processes an audio frame, including sampling, FFT computation, and noise gating.
float *	getVReal ()
	Gets the raw real part of the FFT result.
float *	getVReal (float)
	Gets a smoothed version of the real part of the FFT result.
float	getPeak ()
	Gets the peak frequency detected in the audio.
float	getVolume ()
	Gets the volume level of the audio.
int	getMaxDelta ()
	Gets the maximum delta value between FFT bins.
float *	getDeltas ()
	Gets the delta values between FFT bins.
int *	getSalientFreqs ()
	Gets the salient frequencies detected in the audio.
float	getCentroid ()
	Gets the centroid frequency of the audio spectrum.
bool	getPercussionPresence ()
	Checks for the presence of percussion in the audio.
float	getNoisiness ()
	Gets the noisiness level of the audio.
float *	getFiveBandSplit (int len)
	Calculates and returns a five-band split of the audio spectrum.
void	resetCache ()
	Clears all flags that indicate updated data for getters.

Detailed Description

Handles audio signal processing and feature extraction.

The AudioAnalysis class is responsible for processing real-time audio input, performing Fast Fourier Transform (FFT), and extracting various audio features, such as volume, peak frequency, delta amplitudes, salient frequencies, centroid, percussion presence, and noisiness. It also provides functionality for noise gating and real-time analysis, smoothing, and updating the extracted features for visualization or other uses.

The class interacts with the AudioPrism modules for different types of audio analysis (e.g., volume, peaks, deltas) and stores the results in various buffers. It supports a highly optimized flow for feature extraction while maintaining efficiency for use in embedded systems like the ESP32.

Member Function Documentation

getCentroid()

float AudioAnalysis::getCentroid

(

)

Gets the centroid frequency of the audio spectrum.

Returns

Centroid frequency value.

getDeltas()

float * AudioAnalysis::getDeltas

(

)

Gets the delta values between FFT bins.

Returns

Pointer to the array of delta values.

getFiveBandSplit()

float * AudioAnalysis::getFiveBandSplit

(

int

len

)

Calculates and returns a five-band split of the audio spectrum.

Parameters

len	Length of the audio data.

Returns

Pointer to the array containing five-band split values.

getMaxDelta()

int AudioAnalysis::getMaxDelta

(

)

Gets the maximum delta value between FFT bins.

Returns

Maximum delta value.

getNoisiness()

float AudioAnalysis::getNoisiness

(

)

Gets the noisiness level of the audio.

Returns

Noisiness level.

getPeak()

float AudioAnalysis::getPeak

(

)

Gets the peak frequency detected in the audio.

Returns

Peak frequency value in Hertz.

getPercussionPresence()

bool AudioAnalysis::getPercussionPresence

(

)

Checks for the presence of percussion in the audio.

Returns

True if percussion is detected, false otherwise.

getSalientFreqs()

int * AudioAnalysis::getSalientFreqs

(

)

Gets the salient frequencies detected in the audio.

Returns

Pointer to the array of salient frequencies.

getVolume()

float AudioAnalysis::getVolume

(

)

Gets the volume level of the audio.

Returns

Volume level.

getVReal() [1/2]

float * AudioAnalysis::getVReal

(

)

Gets the raw real part of the FFT result.

Returns

Pointer to the array of real FFT values.

getVReal() [2/2]

float * AudioAnalysis::getVReal

(

float

alpha

)

Gets a smoothed version of the real part of the FFT result.

Parameters

alpha

Smoothing coefficient.

Returns

Pointer to the array of smoothed real FFT values.

processAudioFrame()

void AudioAnalysis::processAudioFrame

(

int

noiseThreshhold

)

Processes an audio frame, including sampling, FFT computation, and noise gating.

Parameters

noiseThreshhold

Threshold used for noise gating.

---

The documentation for this class was generated from the following files:

• main/audio_analysis.h
• main/audio_analysis.cpp