我正在尝试将.MID文件读入Java程序,并希望将每个音符/和弦分开,以便在某种UI上显示它们。我在Java中使用Sequencer API并没有太多运气,并且尝试直接使用MidiFileReader对我来说也不起作用。如果有人想看的话,我会附上我在这里使用的代码:
package miditest;
import java.io.File;
import java.io.IOException;
import javax.sound.midi.InvalidMidiDataException;
import javax.sound.midi.MidiSystem;
import javax.sound.midi.MidiUnavailableException;
import javax.sound.midi.Sequence;
import javax.sound.midi.Sequencer;
public class Main {
public static void main(String[] args) throws InvalidMidiDataException, IOException, MidiUnavailableException{
Sequence sequence = MidiSystem.getSequence(new File("test.mid"));
// Create a sequencer for the sequence
Sequencer sequencer = MidiSystem.getSequencer();
sequencer.open();
sequencer.setSequence(sequence);
// Start playing
sequencer.start();
}
}
答案 0 :(得分:45)
我从未深入研究过Java中的MIDI支持,上一次我认真学习MIDI编程是Commodore Amiga的王者。
看起来你可能需要做很多手工工作。这是一个粗略的例子,它解释了所有的NOTE_ON和NOTE_OFF事件,对于其他事件,它只打印命令号。
它可能看起来比一开始可能想到的更棘手的原因是因为MIDI专注于捕获乐器事件(例如,当按下键盘键时,它被释放时等),而不是乐谱表示法
此代码每个事件打印一行,用tick(表示事件的时间信息),频道,事件类型,音符名称,键,速度
表示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,我在这里躺着的fur elise.mid在开头产生类似的东西:
@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
频道:所有16个MIDI频道都是 支持的。每个频道都可以播放 可变数量的声音(复音)。 每个频道都可以发挥不同 乐器(声音/补丁/音色)。 基于键的打击乐总是在MIDI上 第10频道。
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,它就是您按键的力量。通常它控制声音的音量。有关详情,请参阅此处:http://audio.tutsplus.com/tutorials/production/7-ways-to-use-and-edit-midi-velocity/