我从未深入研究过Java中的MIDI支持,我上一次认真玩MIDI编程是在Commodore Amiga成为王者的时候。
看起来您可能需要做很多手动工作。下面是一个粗略的示例,它解释所有NOTE_ON和NOTE_OFF事件,对于其余事件,它只打印命令编号。
它可能比人们最初想象的要棘手的原因是,MIDI专注于捕获乐器事件(例如,何时按下键盘键,何时释放等),而不是在乐谱符号上。
此代码为每个事件打印出一行,用刻度线(这是事件的计时信息)、通道、事件类型、注释名称、键、速度说明
import java.io.File;
import javax.sound.midi.MidiEvent;
import javax.sound.midi.MidiMessage;
import javax.sound.midi.MidiSystem;
import javax.sound.midi.Sequence;
import javax.sound.midi.ShortMessage;
import javax.sound.midi.Track;
public class Test {
public static final int NOTE_ON = 0x90;
public static final int NOTE_OFF = 0x80;
public static final String[] NOTE_NAMES = {"C", "C#", "D", "D#", "E", "F", "F#", "G", "G#", "A", "A#", "B"};
public static void main(String[] args) throws Exception {
Sequence sequence = MidiSystem.getSequence(new File("test.mid"));
int trackNumber = 0;
for (Track track : sequence.getTracks()) {
trackNumber++;
System.out.println("Track " + trackNumber + ": size = " + track.size());
System.out.println();
for (int i=0; i < track.size(); i++) {
MidiEvent event = track.get(i);
System.out.print("@" + event.getTick() + " ");
MidiMessage message = event.getMessage();
if (message instanceof ShortMessage) {
ShortMessage sm = (ShortMessage) message;
System.out.print("Channel: " + sm.getChannel() + " ");
if (sm.getCommand() == NOTE_ON) {
int key = sm.getData1();
int octave = (key / 12)-1;
int note = key % 12;
String noteName = NOTE_NAMES[note];
int velocity = sm.getData2();
System.out.println("Note on, " + noteName + octave + " key=" + key + " velocity: " + velocity);
} else if (sm.getCommand() == NOTE_OFF) {
int key = sm.getData1();
int octave = (key / 12)-1;
int note = key % 12;
String noteName = NOTE_NAMES[note];
int velocity = sm.getData2();
System.out.println("Note off, " + noteName + octave + " key=" + key + " velocity: " + velocity);
} else {
System.out.println("Command:" + sm.getCommand());
}
} else {
System.out.println("Other message: " + message.getClass());
}
}
System.out.println();
}
}
}
例如,我躺在这里的毛皮elise.mid一开始就会产生这样的东西:
@0 Channel: 1 Note on, E5 key=76 velocity: 127
@192 Channel: 1 Note off, E5 key=76 velocity: 64
@192 Channel: 1 Note on, D#5 key=75 velocity: 127
@384 Channel: 1 Note off, D#5 key=75 velocity: 64
@384 Channel: 1 Note on, E5 key=76 velocity: 127
@576 Channel: 1 Note off, E5 key=76 velocity: 64
@576 Channel: 1 Note on, D#5 key=75 velocity: 127
@768 Channel: 1 Note off, D#5 key=75 velocity: 64
@768 Channel: 1 Note on, E5 key=76 velocity: 127
@960 Channel: 1 Note off, E5 key=76 velocity: 64
@960 Channel: 1 Note on, B4 key=71 velocity: 127
@1152 Channel: 1 Note off, B4 key=71 velocity: 64
@1152 Channel: 1 Note on, D5 key=74 velocity: 127
@1344 Channel: 1 Note off, D5 key=74 velocity: 64
@1344 Channel: 1 Note on, C5 key=72 velocity: 127
@1536 Channel: 1 Note off, C5 key=72 velocity: 64
@1536 Channel: 1 Note on, A4 key=69 velocity: 127
@1920 Channel: 1 Note off, A4 key=69 velocity: 64
更新:通道是 MIDI 规范的 16 个通道。
http://www.midi.org/techspecs/gm.php
通道:支持所有 16 个 MIDI 通道。每个频道可以播放可变数量的声音(复音)。每个通道可以演奏不同的乐器(声音/补丁/音色)。基于键的打击乐始终位于 MIDI 频道 10 上。
速度是用于控制声音的属性之一。例如,在键盘上捕获MIDI数据,这将是您按下键的力。通常它控制声音的音量。有关更多详细信息,请参阅此处:http://audio.tutsplus.com/tutorials/production/7-ways-to-use-and-edit-midi-velocity/