js怎样操作Web Audio节点 6个音频处理技巧打造专业效果

const audioContext = new (window.AudioContext || window.webkitAudioContext)();
const oscillator = audioContext.createOscillator();
const gainNode = audioContext.createGain();

oscillator.connect(gainNode);
gainNode.connect(audioContext.destination); // 连接到扬声器

oscillator.type = 'sine'; // 设置波形
oscillator.frequency.setValueAtTime(440, audioContext.currentTime); // 设置频率为440Hz
gainNode.gain.setValueAtTime(0.5, audioContext.currentTime); // 设置音量为50%

oscillator.start(); // 开始播放

const filter = audioContext.createBiquadFilter();
filter.type = 'lowpass'; // 设置为低通滤波
filter.frequency.setValueAtTime(1000, audioContext.currentTime); // 设置截止频率为1000Hz
filter.Q.setValueAtTime(1, audioContext.currentTime); // 设置Q值（影响滤波器的带宽）

oscillator.connect(filter);
filter.connect(gainNode);

const compressor = audioContext.createDynamicsCompressor();
compressor.threshold.setValueAtTime(-24, audioContext.currentTime); // 阈值，低于此值的信号不会被压缩
compressor.knee.setValueAtTime(30, audioContext.currentTime); // 膝盖，压缩开始的平滑过渡区域
compressor.ratio.setValueAtTime(12, audioContext.currentTime); // 压缩比，输入信号超过阈值后，每增加12dB，输出只增加1dB
compressor.attack.setValueAtTime(0.003, audioContext.currentTime); // 启动时间，压缩器开始工作所需的时间
compressor.release.setValueAtTime(0.25, audioContext.currentTime); // 释放时间，压缩器停止工作所需的时间

gainNode.connect(compressor);
compressor.connect(audioContext.destination);

const stereoPanner = audioContext.createStereoPanner();
stereoPanner.pan.setValueAtTime(1, audioContext.currentTime); // 设置为完全右声道

oscillator.connect(stereoPanner);
stereoPanner.connect(gainNode);

// 假设你已经加载了一个脉冲响应文件 impulseResponseBuffer
const convolver = audioContext.createConvolver();
convolver.buffer = impulseResponseBuffer;

gainNode.connect(convolver);
convolver.connect(audioContext.destination);

const analyser = audioContext.createAnalyser();
analyser.fftSize = 2048; // FFT尺寸，影响频率分辨率
const bufferLength = analyser.frequencyBinCount; // 频率数据长度
const dataArray = new Uint8Array(bufferLength);

oscillator.connect(analyser);
analyser.connect(audioContext.destination);

function draw() {
  requestAnimationFrame(draw);

  analyser.getByteFrequencyData(dataArray); // 获取频率数据

  // 使用dataArray绘制频谱图
  // ...
}

draw();