# node-pitchfinder A compilation of pitch detection algorithms for Node (Using native C++ Addon). Based on [pitchfinder](https://github.com/peterkhayes/pitchfinder), but running a lot faster (because it's native) ## Provided pitch-finding algorithms - **MacLeod** - Best results for instruments - **YIN** - The best balance of accuracy and speed, in my experience. Occasionally provides values that are wildly incorrect. - **AMDF** - Slow and only accurate to around +/- 2%, but finds a frequency more consistenly than others. *NOT AN ADDON* - **Dynamic Wavelet** - Very fast, but struggles to identify lower frequencies. *NOT AN ADDON* - **YIN w/ FFT** *TODO* - **Goertzel** *TODO* ## Installation `npm install --save node-pitchfinder` > For node < 10 use version ^1.x, version 2+ is for node >= 10 ## Usage ### Finding the pitch of a wav file in node ```javascript const fs = require('fs') const WavDecoder = require('wav-decoder') const { YIN } = require('node-pitchfinder') // see below for option parameters. const detectPitch = YIN({ sampleRate: 44100 }) const buffer = fs.readFileSync(PATH_TO_FILE) const decoded = WavDecoder.decode(buffer) // get audio data from file using `wav-decoder` const float64Array = decoded.channelData[0] // get a single channel of sound const pitch = detectPitch(float64Array) // All detectors are using float64Array internally, but you can also give an ordinary array of numbers ``` ## Configuration ### All detectors - `sampleRate` - defaults to 44100 ### YIN - `threshold` - used by the algorithm - `probabilityThreshold` - don't return a pitch if probability estimate is below this number. ### AMDF - `minFrequency` - Lowest frequency detectable - `maxFrequency` - Highest frequency detectable - `sensitivity` - `ratio` ### MacLeod - `bufferSize` - Maximum data size (default 1024) - `cutoff` - Defines the relative size the chosen peak (pitch) has. 0.93 means: choose the first peak that is higher than 93% of the highest peak detected. 93% is the default value used in the Tartini user interface. - `freqCutoff` - Minimum frequency to be detected (default 80Hz) - `probabilityThreshold` - don't return a pitch if probability estimate is below this number. ### Dynamic Wavelet *no special config* ## MORE API ### YIN and MacLeod - method: getResult (data) - does not use probabilityThreshold, returns an object with probability instead, like `{ pitch: number, probability: number }` #### Usage ```js const {MacLeod} = require('node-pitchfinder') const detectPitch = MacLeod().getResult detectPitch(data) // {pitch: 440, probability: 1} ``` ## Todo - MacLeod using FFT ## Thanks Several of these algorithms were ported from Jonas Six's excellent TarsosDSP library (written in Java). If you're looking for a far deeper set of tools than this, check out his work [on his website](http://tarsos.0110.be/tag/TarsosDSP) or [on Github](https://github.com/JorenSix/TarsosDSP). Thanks to Aubio for his [YIN code](https://github.com/aubio/aubio/blob/master/src/pitch/pitchyin.c)