使用 javax.sound.midi 接收 midi 输入

Question

我想要一个程序，当它获得 MIDI 输入时可以做一些事情。

例如，当我点击控制器上的按钮 1 时，它应该打印 "You clicked btn 1"，而当我点击按钮 2 时，它应该打印 "You clicked btn 2".

我尝试使用 javax.sound.midi 库，但论坛或 youtube 上的所有示例均无效。

这对我来说最有效。它打印了我 PC 的所有 Midi 设备，但没有收到任何东西。有人可以帮忙吗？

package de.snke.dev;

import javax.sound.midi.*;;



public class Main  extends Object implements Receiver{

static MidiClass myMidi;

public static void main(String[] args) throws Exception {

    MidiDevice.Info[] info =
             MidiSystem.getMidiDeviceInfo();

            for (int i=0; i < info.length; i++) {
             System.out.println(i + ") " + info[i]);
             System.out.println("Name: " + info[i].getName());
             System.out.println("Description: " +
             info[i].getDescription());

             MidiDevice device =
            MidiSystem.getMidiDevice(info[i]);
             System.out.println("Device: " + device);
            }

}

public void send(MidiMessage msg,
        long time) {
        System.out.println("Received message " + msg);
        }

        public void close() {
        System.out.println("Closing");
        }
}

编辑：现在我有

Sequencer           seq;
Transmitter         seqTrans;
Synthesizer         synth;
Receiver         synthRcvr;
try {
      seq     = MidiSystem.getSequencer();
      seqTrans = seq.getTransmitter();
      synth   = MidiSystem.getSynthesizer();
      synthRcvr = synth.getReceiver(); 
      seqTrans.setReceiver(synthRcvr);      
} catch (MidiUnavailableException e) {
      // handle or throw exception
}

我现在连接到我的 APC Mini 了吗？对不起我是初学者... 如果是，我现在如何读取 MIDI 输入？如果否，我需要更改什么？

Answer 1

解决方法是：

package de.snke.dev;

import javax.sound.midi.*;
import java.util.ArrayList;
import java.util.List;
import java.io.*;

public class Main
{

public void Main()
{
    MidiDevice device;
    MidiDevice.Info[] infos = MidiSystem.getMidiDeviceInfo();
    for (int i = 0; i < infos.length; i++) {
        try {
        device = MidiSystem.getMidiDevice(infos[i]);
        //does the device have any transmitters?
        //if it does, add it to the device list
        System.out.println(infos[i]);

        //get all transmitters
        List<Transmitter> transmitters = device.getTransmitters();
        //and for each transmitter

        for(int j = 0; j<transmitters.size();j++) {
            //create a new receiver
            transmitters.get(j).setReceiver(
                    //using my own MidiInputReceiver
                    new MidiInputReceiver(device.getDeviceInfo().toString())
            );
        }

        Transmitter trans = device.getTransmitter();
        trans.setReceiver(new MidiInputReceiver(device.getDeviceInfo().toString()));

        //open each device
        device.open();
        //if code gets this far without throwing an exception
        //print a success message
        System.out.println(device.getDeviceInfo()+" Was Opened");


    } catch (MidiUnavailableException e) {}
}


}
//tried to write my own class. I thought the send method handles an MidiEvents sent to it
public class MidiInputReceiver implements Receiver {
public String name;
public MidiInputReceiver(String name) {
    this.name = name;
}
public void send(MidiMessage msg, long timeStamp) {


    byte[] aMsg = msg.getMessage();
    // take the MidiMessage msg and store it in a byte array

    // msg.getLength() returns the length of the message in bytes
    for(int i=0;i<msg.getLength();i++){
        System.out.println(aMsg[i]);
        // aMsg[0] is something, velocity maybe? Not 100% sure.
        // aMsg[1] is the note value as an int. This is the important one.
        // aMsg[2] is pressed or not (0/100), it sends 100 when they key goes down,  
        // and 0 when the key is back up again. With a better keyboard it could maybe
        // send continuous values between then for how quickly it's pressed? 
        // I'm only using VMPK for testing on the go, so it's either 
        // clicked or not.
    }
    System.out.println();
}
public void close() {}
}
}

它是 2 线程解决方案，可以打开所有 MIDI 设备并打印它们的速度、音符值和状态（是否被点击）

别忘了！

你必须打电话给

Main main = new Main();
main.Main();

在单独的 class 中启动 class Main 中的 Main 方法。

使用 javax.sound.midi 接收 midi 输入

Receive midi input with javax.sound.midi

midi

receiver

javax.sound.midi