Java Midi Sequencer 录音后不播放

Question

我写了一个小的 midi 录音机，它应该在之后播放曲目：

Sequencer seqr=MidiSystem.getSequencer();

//Transmitters and receivers here

seqr.startRecording();

//Some Stuff (basically waiting)

seqr.stopRecording();
seqr.setTickPosition(0);
seqr.setLoopStartPoint(0);
seqr.setLoopEndPoint(seqr.getTickLength());
seqr.setLoopCount(Sequencer.LOOP_CONTINUOUSLY);
seqr.start();

它没有，但是 - 这让我感到困惑 - 如果我添加：

File midFile=new File("MyMidiFile.mid");
MidiSystem.write(seqr.getSequence(), 1, midFile);
seqr.setSequence(MidiSystem.getSequence(midFile));

在播放 stopRecoding() 之后，

这表明录音和播放都正常。

//问题结束

编辑

我要求的整个 midi 代码

发送器和接收器

public static MidiDevice inputDevice;
public static MidiDevice outputDevice;
public static Transmitter usbTransmitter;
public static Receiver usbReciever;

public static Sequencer seqr;
public static Transmitter seqTransmitter;
public static Receiver seqReciever;

初始化：

try{
    seqr = MidiSystem.getSequencer();

    Info[] midiDeviceInfo = MidiSystem.getMidiDeviceInfo();

    inputDevice = MidiSystem.getMidiDevice(midiDeviceInfo[1]);
    outputDevice = MidiSystem.getMidiDevice(midiDeviceInfo[4]);
    seqr = MidiSystem.getSequencer();
    inputDevice.open();
    outputDevice.open();
    seqr.open();

    seqReciever = seqr.getReceiver();
    seqTransmitter = seqr.getTransmitters().get(0);

    usbTransmitter = inputDevice.getTransmitter();
    usbReciever = outputDevice.getReceiver();
    usbTransmitter.setReceiver(seqReciever);
    seqTransmitter.setReceiver(usbReciever);

    Sequence seq = new Sequence(Sequence.PPQ, 24);

    seqr.setSequence(seq);
    seqr.setTickPosition(0);
} catch (MidiUnavailableException | InvalidMidiDataException e) {
    e.printStackTrace();
}

录音：

Track track;
Sequencer seqr;
Sequence seq;

public TrackControler(Sequencer seqr) {
    this.seqr = seqr;
    this.seq = seqr.getSequence();
    this.track = seq.createTrack();
}

private void startRecordNow() {
    seqr.recordEnable(track, -1);
    seqr.startRecording();
}

private void endRecordNow() {
    seqr.stopRecording();

    seqr.setTickPosition(0);
    seqr.setLoopStartPoint(0);
    seqr.setLoopEndPoint(seqr.getTickLength());
    seqr.setLoopCount(Sequencer.LOOP_CONTINUOUSLY);
    seqr.start();
}

Answer 1

在没有看到您的 MIDI 录音或播放代码的情况下，我不得不猜测 MidiSystem.write() 或 Sequencer.setSequence() 正在执行一些您忽略的初始化。我的第二个猜测是 Sequencer.stopRecording() 没有让事情处于正确的状态以供播放。

这是我在没有更多信息的情况下所能做的最好的。

更新（这样你就不用翻看评论了）：

似乎 Java 做了一些缓存，需要像 seqr.setSequence(seqr.getSequence() 这样的东西来提交缓存。我一直在寻找一种更直接的方法来做到这一点，但还没有找到任何东西。

Java Midi Sequencer 录音后不播放

Java Midi Sequencer doesn't play after recording

java

midi