funkin.backend.utils.AudioAnalyzer

An utility that analyze FlxSounds, can be used to make waveform or real-time audio visualizer.

FlxSound.amplitude does work in CNE so if any case if your only checking for peak of current time, use that instead.

Static methods

`staticgetByte(buffer:ArrayBuffer, position:Int, wordSize:Int):Int`

Get bytes from an audio buffer with specified position and wordSize

Parameters:

`buffer`	The audio buffer to get byte from.
`position`	The specified position to get the byte from the audio buffer.
`wordSize`	How many bytes to get with to one byte (Usually it's bitsPerSample / 8 or bitsPerSample >> 3).

Returns:

Byte from the audio buffer with specified position.

View on GitHub

`staticgetFrequenciesFromSamples(samples:Array<Float>, fftN:Int = 2048, useWindowing:Bool = false, ?frequencies:Array<Float>):Array<Float>`

Gets frequencies from the samples.

Parameters:

`samples`	The samples (can be from AudioAnalyzer.getSamples).
`fftN`	How much samples for the fft to get, Has to be power of two, or it won't work.
`useWindowing`	Should fft related stuff use blackman windowing? (Web AnalyzerNode windowing), Most of the time it's not worth it.
`frequencies`	The output for getting the frequencies, to avoid memory leaks (Optional).

Returns:

Output of frequencies.

View on GitHub

`staticgetLevelsFromFrequencies(frequencies:Array<Float>, sampleRate:Int, barCount:Int, ?levels:Array<Float>, ratio:Float = 0.0, minDb:Float = -63.0, maxDb:Float = -10.0, minFreq:Float = 20.0, maxFreq:Float = 22000.0):Array<Float>`

Gets levels from the frequencies with specified sample rate.

Parameters:

`frequencies`	Frequencies input.
`sampleRate`	Sample Rate input.
`barCount`	How much bars to get.
`levels`	The output for getting the values, to avoid memory leaks (Optional).
`ratio`	How much ratio for smoothen the values from the previous levels values (Optional, use CoolUtil.getFPSRatio(1 - ratio) to simulate web AnalyserNode.smoothingTimeConstant, 0.35 of smoothingTime works most of the time).
`minDb`	The minimum decibels to cap (Optional, default -63.0, -120 is pure silence).
`maxDb`	The maximum decibels to cap (Optional, default -10.0, Above 0 is not recommended).
`minFreq`	The minimum frequency to cap (Optional, default 20.0, Below 8.0 is not recommended).
`maxFreq`	The maximum frequency to cap (Optional, default 22000.0, Above 23000.0 is not recommended).

Returns:

Output of levels/bars that ranges from 0 to 1.

Constructor

View on GitHub

`new(sound:FlxSound, fftN:Int = 2048, useWindowingFFT:Bool = false)`

Creates an analyzer for specified FlxSound

Parameters:

`sound`	An FlxSound to analyze.
`fftN`	How much samples for fft to get (Optional, default 2048, 4096 is recommended for highest quality).
`useWindowingFFT`	Should fft related stuff use blackman windowing? (Web AnalyzerNode windowing).

Variables

`read onlybuffer:AudioBuffer`

The current buffer from sound.

`read onlybyteSize:Int`

The current byteSize from buffer. Example the byteSize of 16 BitsPerSample is 32768 (1 << 16-1)

`fftN:Int`

How much samples for the fft to get. Usually for getting the levels or frequencies of the sound.

Has to be power of two, or it won't work.

`sound:FlxSound`

The current sound to analyze.

`useWindowingFFT:Bool`

Should fft related stuff use blackman windowing? (Web AnalyzerNode windowing). Most of the time looks bad with this.

Methods

View on GitHub

`analyze(startPos:Float, endPos:Float, ?outOrOutMin:Array<Float>, ?outMax:Array<Float>):Float`

Analyzes an attached FlxSound from startPos to endPos in milliseconds to get the amplitudes.

Parameters:

`startPos`	Start Position to get from sound in milliseconds.
`endPos`	End Position to get from sound in milliseconds.
`outOrOutMin`	The output minimum value from the analyzer, indices is in channels (0 to -0.5 -> 0 to 0.5) (Optional, if outMax doesn't get passed in, it will be [min, max] with all channels combined instead).
`outMax`	The output maximum value from the analyzer, indices is in channels (Optional).

Returns:

Output of amplitude from given position.

View on GitHub

`getFrequencies(startPos:Float, ?volume:Float, ?frequencies:Array<Float>):Array<Float>`

Gets frequencies from an attached FlxSound from startPos.

Parameters:

`startPos`	Start Position to get from sound in milliseconds.
`volume`	How much volume multiplier will it affect the output. (Optional, default 1.0).
`frequencies`	The output for getting the frequencies, to avoid memory leaks (Optional).

Returns:

Output of frequencies.

View on GitHub

`getLevels(startPos:Float, ?volume:Float, barCount:Int, ?levels:Array<Float>, ?ratio:Float, ?minDb:Float, ?maxDb:Float, ?minFreq:Float, ?maxFreq:Float):Array<Float>`

Gets levels from an attached FlxSound from startPos, basically a minimized of frequencies.

Parameters:

`startPos`	Start Position to get from sound in milliseconds.
`volume`	How much volume multiplier will it affect the output. (Optional, default 1.0).
`barCount`	How much bars to get.
`levels`	The output for getting the values, to avoid memory leaks (Optional).
`ratio`	How much ratio for smoothen the values from the previous levels values (Optional, use CoolUtil.getFPSRatio(1 - ratio) to simulate web AnalyserNode.smoothingTimeConstant, 0.35 of smoothingTime works most of the time).
`minDb`	The minimum decibels to cap (Optional, default -63.0, -120 is pure silence).
`maxDb`	The maximum decibels to cap (Optional, default -10.0, Above 0 is not recommended).
`minFreq`	The minimum frequency to cap (Optional, default 20.0, Below 8.0 is not recommended).
`maxFreq`	The maximum frequency to cap (Optional, default 22000.0, Above 23000.0 is not recommended).

Returns:

Output of levels/bars that ranges from 0 to 1.

View on GitHub

`getSamples(startPos:Float, length:Int, mono:Bool = true, channel:Int = -1, volume:Float = 1.0, ?output:Array<Float>, outputMerge:Bool = false):Array<Float>`

Gets samples from startPos with given length of samples.

Parameters:

`startPos`	Start Position to get from sound in milliseconds.
`length`	Length of Samples.
`mono`	Merge all of the byte channels of samples in one channel instead (Optional).
`channel`	What channels to get from? (-1 == All Channels, Optional, this will be ignored if mono is enabled).
`volume`	How much volume multiplier will it affect the output. (Optional, default 1.0).
`output`	An Output that gets passed into this function, usually for to avoid memory leaks (Optional).
`outputMerge`	Merge with previous values (Optional, default false).

Returns:

Output of samples.

View on GitHub

`read(startPos:Float, endPos:Float, callback:AudioAnalyzerCallback):Void`

Read an attached FlxSound from startPos to endPos in milliseconds with a callback.

Parameters:

`startPos`	Start Position to get from sound in milliseconds.
`endPos`	End Position to get from sound in milliseconds.
`callback`	Int->Int->Void Byte->Channels->Void Callback to get the byte of a sample.