Vue を使用してオーディオ ファイルの統計グラフを実装する方法

vue create audio-chart

cd audio-chart
npm install vue-chartjs chart.js --save

<template>
  <canvas ref="chart" ></canvas>
</template>

<script>
import { Bar } from "vue-chartjs";

export default {
  extends: Bar,
  props: ['chartData', 'options'],
  mounted() {
    this.renderChart(this.chartData, this.options);
  }
};
</script>

<template>
  <div>
    <input type="file" @change="handleFileChange">
    <BarChart :chartData="chartData" :options="chartOptions" />
  </div>
</template>

<script>
import BarChart from './BarChart.vue';

export default {
  components: { BarChart },
  data() {
    return {
      chartData: null,
      chartOptions: {
        responsive: true,
        scales: {
          yAxes: [
            {
              ticks: {
                beginAtZero: true
              }
            }
          ]
        },
        maintainAspectRatio: false
      }
    };
  },
  methods: {
    handleFileChange(e) {
      const file = e.target.files[0];
      this.readFile(file);
    },
    readFile(file) {
      // 利用FileReader API读取音频文件数据
      const reader = new FileReader();
      reader.onload = () => {
        const arrayBuffer = reader.result;
        this.getAudioData(arrayBuffer);
      };
      reader.readAsArrayBuffer(file);
    },
    getAudioData(arrayBuffer) {
      // 使用Web Audio API获取音频数据
      const audioContext = new (window.AudioContext || window.webkitAudioContext)();
      audioContext.decodeAudioData(arrayBuffer, (buffer) => {
        const audioData = buffer.getChannelData(0); // 只获取左声道的音频数据
        this.processAudioData(audioData);
      });
    },
    processAudioData(audioData) {
      // 处理音频数据，生成图表数据
      const chartData = {
        labels: [],
        datasets: [
          {
            label: "Amplitude",
            backgroundColor: "rgba(75,192,192,0.4)",
            borderColor: "rgba(75,192,192,1)",
            borderWidth: 1,
            data: []
          }
        ]
      };
      for (let i = 0; i < audioData.length; i += 100) { // 每隔100个样本点取一个数据，可根据需要调整
        chartData.labels.push(i);
        chartData.datasets[0].data.push(audioData[i]);
      }
      this.chartData = chartData;
    }
  }
};
</script>

<template>
  <div id="app">
    <AudioFile />
  </div>
</template>

<script>
import AudioFile from './components/AudioFile.vue';

export default {
  name: "App",
  components: {
    AudioFile
  }
};
</script>

npm run serve