如何使用网络音频制作用于创建振荡器节点的函数 Api

Question

我知道这听起来很简单或显而易见，但我做不到。

查看此片段：

ctx = new AudioContext();
gain = ctx.createGain();
gain.connect(ctx.destination);
gain.gain.value = 0.5;


osc1 = ctx.createOscillator();
osc1.connect(gain);
osc1.frequency.value = 450;
osc1.start();
osc1.stop(2);

osc2 = ctx.createOscillator();
osc2.connect(gain);
osc2.frequency.value = 500;
osc2.start();
osc2.stop(2);
console.log("playing");

它同时播放两个振荡器没有问题，但它重复代码。如果我尝试将冗余代码放入函数中，它不起作用。

ctx = new AudioContext();
gain = ctx.createGain();
createAndPlayOsc(450);
createAndPlayOsc(500);


function createAndPlayOsc(freq){
    console.log("creating osc with freq " + freq);
    var osc = ctx.createOscillator();
    osc.connect(gain);
    osc.frequency.value = freq;
    osc.start();
    osc.stop(2);
    console.log("playing osc with freq " + freq);
}

即使我发送 AudioContext

ctx = new AudioContext();
gain = ctx.createGain();
createAndPlayOsc(450, ctx);
createAndPlayOsc(500, ctx);


function createAndPlayOsc(freq, context){
    console.log("creating osc with freq " + freq);
    var osc = context.createOscillator();
    osc.connect(gain);
    osc.frequency.value = freq;
    osc.start();
    osc.stop(2);
    console.log("playing osc with freq " + freq);
}

或者 gainNode 和 context

ctx = new AudioContext();
gain = ctx.createGain();
createAndPlayOsc(450, ctx, gain);
createAndPlayOsc(500, ctx, gain);


function createAndPlayOsc(freq, context, gainNode){
    console.log("creating osc with freq " + freq);
    var osc = context.createOscillator();
    osc.connect(gainNode);
    osc.frequency.value = freq;
    osc.start();
    osc.stop(2);
    console.log("playing osc with freq " + freq);
}

我错过了什么？

Answer 1

您忘记将增益与上下文联系起来：

gain.connect(ctx.destination);

如何使用网络音频制作用于创建振荡器节点的函数 Api

How to make a function for create oscillatorNodes using Web Audio Api

javascript

web-audio-api