The following method converts midi files in the attachment compression package to die and does not return results

[Titans1001]

The following method converts midi files in the attachment compression package to die and does not return results

`async function midiToPCM(midiFile, config = {}) {
try {
// 默认渲染配置
const defaultConfig = {
batchSize: 100,
minNoteDuration: 0.1,
maxPolyphony: 10,
oscillator: { type: "sawtooth" },
envelope: { attack: 0.1, decay: 0.2, sustain: 0.8, release: 0.3 },
};
const renderConfig = { ...defaultConfig, ...config };

// 1. 解析 MIDI 文件
const midiData = midiFile instanceof File ? await midiFile.arrayBuffer() : midiFile;
console.log("🍎🍎🍎🍎MIDI 数据:", midiData);

const midi = new Midi(midiData);
const channels = midi.tracks.length;
let timer = null;
// 2. 使用 Tone.js 离线渲染 MIDI 数据
let audioBuffer = null

audioBuffer = await Tone.Offline(async (context) => {
  // 设置渲染参数
  const synth = new Tone.PolySynth(Tone.Synth, {
    maxPolyphony: renderConfig.maxPolyphony,
    // oscillator: renderConfig.oscillator,
    // envelope: renderConfig.envelope,
  }).toDestination();

  for (let track of midi.tracks) {
    console.log(`Rendering track: ${track.name || "Unnamed"}`);
    for (let i = 0; i < track.notes.length; i += 1) {
      const note = track.notes[i];
      if (note.duration > renderConfig.minNoteDuration) {
        console.log(`🍎🍎🍎🍎🍎🍎Playing note: ${note.name} at time: ${note.time} in duration: ${note.duration}`);
        synth.triggerAttackRelease(note.name, note.duration, note.time);
        // 小间隔，避免长时间阻塞
        await new Promise(resolve => setTimeout(resolve, 0));
      }
      if (i == track.notes.length - 1) {
        console.log("🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎🍎", context);
        timer = setTimeout(async () => {
          if (audioBuffer == null) {
            context.transport.stop(); // 停止播放
            context.dispose(); // 释放资源
            console.log("渲染超时，提前终止");
            throw new Error("渲染超时，提前终止");
          } else {
            console.log("渲染超时，提前终止");
            throw new Error("渲染超时，提前终止");
          }
        }, 15 * 1000)
      }
    }
  }
}, midi.duration, channels, 44100);

clearTimeout(timer);
// 3. 提取 PCM 数据
const pcmData = [];
for (let i = 0; i < channels; i++) {
  pcmData.push(audioBuffer.getChannelData(i).slice());
}

return {
  pcmData,
  channels,
  sampleRate: audioBuffer.sampleRate,
  duration: audioBuffer.duration,
};

} catch (error) {
clearTimeout(timer);
console.error("MIDI 转 PCM 失败：", error.message);
throw new Error(MIDI 转 PCM 失败: ${error.message});
}
}

EveningWalk.mid.zip
function convertPCMToMP3(pcmData, sampleRate = 44100, channels = 2, bitrate = 128) {
return new Promise((resolve, reject) => {
try {
// 初始化 MP3 编码器
const mp3Encoder = new lamejs.Mp3Encoder(channels, sampleRate, bitrate);

  // 创建一个新的 MP3 编码数据
  const mp3Data = [];

  // 合并所有通道的 PCM 数据
  const interleavedPCMData = new Float32Array(pcmData[0].length * channels);
  // 
  let offset = 0;
  for (let i = 0; i < pcmData[0].length; i++) {
    for (let channel = 0; channel < channels; channel++) {
      interleavedPCMData[offset++] = pcmData[channel][i];
    }
  }

  // 将 PCM 数据转成 16-bit 格式
  const pcmData16Bit = new Int16Array(interleavedPCMData.length);
  for (let i = 0; i < interleavedPCMData.length; i++) {
    pcmData16Bit[i] = Math.max(-32768, Math.min(32767, interleavedPCMData[i] * 32767)); // 防止溢出
  }

  // 编码 PCM 数据
  const mp3Buffer = mp3Encoder.encodeBuffer(pcmData16Bit);
  if (mp3Buffer.length > 0) {
    mp3Data.push(new Int8Array(mp3Buffer));
  }

  // 完成 MP3 编码并生成文件
  const finalBuffer = mp3Encoder.flush();
  if (finalBuffer.length > 0) {
    mp3Data.push(new Int8Array(finalBuffer));
  }

  // 将 MP3 数据转为 Blob 对象
  const blob = new Blob(mp3Data, { type: 'audio/mp3' });
  resolve({
    blob,
    file: new File([blob], 'output.mp3', { type: 'audio/mp3' }),
    blobUrl: URL.createObjectURL(blob),
  });
} catch (error) {

  reject(error);
}

});
}
const convertMidiFileToMp3 = (midiFile) => {
return new Promise(async (resolve, reject) => {
try {
const midiToPCMData = await midiToPCM(midiFile);
const mp3Result = await convertPCMToMP3(midiToPCMData.pcmData, midiToPCMData.sampleRate, midiToPCMData.channels);
resolve(mp3Result);
} catch (error) {
reject(error);
}
})
}`