我正在尝试用 Java 编写一个非常简单的声音合成器。我正在使用该javax.sound.sampled
软件包。下面的代码有效,但正弦波非常嘈杂,听起来像在波旁播放某种安静的温暖噪音。
try {
double sampleRate = 44100;
//8 bits per sample, so a byte.
AudioFormat audioFormat = new AudioFormat((float) sampleRate, 8, 1, true, false);
SourceDataLine line = AudioSystem.getSourceDataLine(audioFormat);
line.open(audioFormat);
line.start();
//A4
double freq = 440.0;
byte[] buf = new byte[1];
//the formula for a sample is amplitude * sin(2.0 * PI * freq * time)
for (int i = 0; i < sampleRate; i++) {
double t = (i / (sampleRate - 1));
double sample = 0.1 * Math.sin(2.0 * Math.PI * freq * t);
//scaling the sound from -1, 1 to -127, 127
buf[0] = (byte) (sample * (double) Byte.MAX_VALUE);
line.write(buf, 0, 1);
}
line.drain();
line.stop();
line.close();
} catch (Exception e) {
throw new RuntimeException(e);
}
我将生成的声音放入 EQ 中,以验证声音是否真的很嘈杂,果然:
主要频率是 440 赫兹,但还有一些其他频率不应该出现。为什么会这样?我如何解决它?