Is it possible to detect all the chords in a single audio file?

[pallocchi]

Hi! I'm using the library as the documentation explains:

String pathFile = "/path/to/file.wav";
Signal signal = new WAVFile(new File(pathFile)).getSamples(0);

try (ChordPredictor predictor = ChordPredictor.getInstance()) {
    String chord = predictor.predict(CRPVectorFactory.from_signal(signal));
    System.out.println("Predicted chord: "+chord);
}

My audio file is 28 seconds long, and it has ~20 guitar chords.
However, the predictor was able to detect 1 chord only.
Since the predict method returns just a string, I guess I'm using it wrong.
How should I use the library for this use case?

Thanks,

[nojux-official]

Your code just predicts a chord from all samples.

I modified the CLIChordRecognizer example to extract chords from wav file instead of a microphone and my code is:

import com.github.zukarusan.jchoreco.system.ChordProcessor;
import java.io.File;
import java.io.IOException;
import java.io.PrintStream;
import java.util.Scanner;

import javax.sound.sampled.UnsupportedAudioFileException;
import be.tarsos.dsp.AudioDispatcher;
import be.tarsos.dsp.io.jvm.AudioDispatcherFactory;

public class ExtractFromWav {
    static final float SAMPLE_RATE = 44100;
    static final int BUFFER_SIZE = 44100;
    static Thread chordThread = null;

    public static void main(String[] args) throws IOException, UnsupportedAudioFileException {
        ChordProcessor.isDebug = false;

        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter file path:");
        String fileName = scanner.nextLine();

        System.out.println("Processing: " + fileName);
        File file = new File(fileName);
        AudioDispatcher dispatcher = AudioDispatcherFactory.fromFile(file, BUFFER_SIZE, BUFFER_SIZE / 2);

        PrintStream output_chords = new PrintStream(System.out);
        ChordProcessor chordProcessor = new ChordProcessor(SAMPLE_RATE, BUFFER_SIZE, output_chords);
        dispatcher.addAudioProcessor(chordProcessor);

        Runtime.getRuntime().addShutdownHook(new Thread(() -> {
            System.out.println("Releasing Resources");
            chordProcessor.close();
        }));


        chordThread = new Thread(dispatcher, "Chord recognizer");
        chordThread.start();

        while (chordThread.isAlive()) {
        }

        chordThread.interrupt();
        dispatcher.stop();
        chordProcessor.close();
        System.exit(0);
    }
}

Still, this code needs some changes, but I think it can be a starting point.