ofxAubio beat detector sent over OSC.

beat-detect-osc.cpp

// Example settings.xml:
//
//    {
//        "destination": "localhost",
//        "port": 9090,
//        "device": 2
//    }

#include "ofMain.h"
#include "ofEventUtils.h"
#include "ofxOsc.h"
#include "ofxAubio.h"
#include "ofxGui.h"
#include "ofJson.h"

class ofApp : public ofBaseApp {
public:
    ofxAubioBeat beat;
    ofxAubioMelBands bands;
    
    float lastBeat;
    float fadeOut = .25;
    float maxEnergy = 0;

    vector<ofSoundDevice> devices;
    ofxOscSender oscOut;

    void setup(){
        ofSetFrameRate(60);
        ofSetBackgroundAuto(false);
        
        ofJson settings = ofLoadJson("settings.json");
        
        beat.setup();
        ofAddListener(beat.gotBeat, this, &ofApp::beatEvent);
        
        bands.setup();
        
        devices = ofSoundStreamListDevices();
        ofSoundStreamSettings soundSettings;
        soundSettings.setInDevice(devices[settings["device"]]);
        soundSettings.numInputChannels = 2;
        soundSettings.numOutputChannels = 0;
        soundSettings.setInListener(ofGetAppPtr());
        ofSoundStreamSetup(soundSettings);
        
        oscOut.setup(settings["destination"], settings["port"]);
    }

    void exit(){
        ofSoundStreamStop();
        ofSoundStreamClose();
    }

    void audioIn(float * input, int bufferSize, int nChannels){
        beat.audioIn(input, bufferSize, nChannels);
        bands.audioIn(input, bufferSize, nChannels);
    }

    void update(){
    }

    void draw(){
        // update beat info
        float beatTime = ofGetElapsedTimef() - lastBeat;
        float alpha = ofMap(beatTime, 0, fadeOut, 255, 0, true);
        ofClear(alpha);
        
        // draw bands
        ofSetColor(255);
        ofSetLineWidth(3.);
        ofPolyline bandPlot;
        float curMaxEnergy = 0;
        for (int i = 0; i < bands.nBands; i++) {
            float energy = bands.energies[i];
            curMaxEnergy = MAX(energy, curMaxEnergy);
            float x = ofMap(i, 0, bands.nBands - 1, 0, 1);
            float y = ofMap(bands.energies[i], 0, maxEnergy, 1, 0, true);
            bandPlot.addVertex(ofVec3f(x, y, 0));
        }
        maxEnergy = MAX(curMaxEnergy, maxEnergy);
        ofDrawBitmapString("Max Energy: " + ofToString(int(100 * maxEnergy)), 10, 20);
        ofDrawBitmapString(ofToString(beat.bpm) + " bpm", 10, 40);
        ofScale(ofGetWidth(), ofGetHeight());
        bandPlot.draw();
    }

    void beatEvent(float & time) {
        lastBeat = ofGetElapsedTimef();
        ofxOscMessage msg;
        msg.setAddress("/beat");
        oscOut.sendMessage(msg);
    }
};
    
int main() {
    ofSetupOpenGL(640, 240, OF_WINDOW);
    ofRunApp(new ofApp());
}