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我正在尝试使用 WebAudio api 在 html 中播放由 ROS audio_capture 生成的流式 mp3 消息（uint8 字节）。

消息由 ROS audio_capture 生成，它将 mp3 发布为 uint8 字节。我正在抓取每条消息并尝试使用网络音频 api 在网络浏览器中播放它。

以下是示例 mp3 消息：

data: [255, 243, 152, 68, 193, 22, 185, 255, 114, 223, 97, 38, 124, 172, 27, 246, 218, 254, 194, 80, 189, 84, 180, 209, 56, 254, 114, 135, 214, 30, 151, 78, 75, 159, 104, 148, 93, 149, 152, 155, 66, 68, 77, 137, 197, 34, 132, 145, 8, 138, 163, 10, 159, 17, 160, 23, 78, 4, 43, 174, 73, 201, 40, 63, 17, 28, 209, 153, 70, 81, 180, 42, 180, 226, 199, 155, 79, 189, 189, 51, 135, 145, 183, 139, 206, 179, 81, 185, 55, 158, 158, 89, 168, 133, 27, 112, 101, 139, 143, 24, 73, 193, 5, 201, 195, 32, 81, 205, 100, 189, 224, 214, 122, 225, 61, 221, 74, 155, 134, 73, 229, 200, 24, 71, 83, 118, 86, 245, 166, 149, 53, 187, 113, 23, 17, 124, 43, 40, 232, 206, 60, 171, 168, 41, 158, 44, 112, 218, 54, 123, 29, 123, 163, 99, 79, 94, 174, 49, 242, 214, 50, 238, 153, 95, 57, 221, 223, 129, 247, 35, 157, 50, 77, 52, 69, 119, 110, 70, 44, 83, 84, 85, 141, 220, 190, 12, 85, 81, 24, 2, 122, 169, 36, 150, 238, 0, 232, 21, 230, 42, 96, 104, 226, 58, 78, 169, 244, 172, 228, 145, 76, 173, 170, 129, 62, 173, 50, 73, 91, 246, 17, 201, 6, 36, 101, 70, 69, 42, 146, 182, 124, 54, 11, 164, 78, 43, 44, 166, 188, 233, 96, 170, 171, 123, 66, 202, 107, 172, 152, 150, 143, 54, 68, 85, 70, 15, 3, 147, 69, 205, 25, 64, 210, 175, 185, 48, 165, 166, 94, 101, 85, 3, 36, 66, 99, 232, 153, 102, 196, 75, 152, 133, 79, 206, 202, 226, 158, 140, 158, 69, 221, 1, 70, 217, 193, 204, 138, 48, 138, 76, 127, 88, 211, 52, 173, 249, 85, 63, 201, 204, 210, 86, 42, 28, 135, 255, 187, 122, 220, 51, 27, 45, 238, 104, 73, 101, 165, 63, 190, 110, 102, 247, 66, 218, 251, 79, 131, 181, 44, 92, 167, 133, 160, 155, 228, 102, 119, 151, 159, 105, 85, 235, 145, 60, 252, 125, 120, 73, 211, 98]

在下面提到的 base64 解码之前从音频源接收的原始数据，如果它不是有效的 mp3 格式，请告诉我。

//OYRM0VceN1L2EjfqzL/sJWwwydElS3xJYcJKpYaLXtfXvddaz6w5T+8w8/p6du6oWOCT6zoDp+zx9GnhKa8j0MGzMgZEs3bs5Z+x0InDcmNueXnI5J+eVwfp9emvuEZ2Oy2mNa7P3YYm+eK90yG6ktKsaInN/SpHvPlpxWo92+lBsUa9GHQagbEyziEbey/u8pi28oYYYW6B5mt0jZk1Ob7IFLsMIKSlOT3W2WXmcPS1Mhc0KIUiDkQ4IelkEbh6+OfQ/2llZ0karuqgLm5UZmFiYKwpE4wJMp0skT+cEmnaGUBIwvvpdXGyMCIEEEJAuQRTlJZtZoV0xGzMpG5tM+6ae6QKo5vTV2cmIBtiktmtOaqyQgxndQE/iCQQLCgpB8HVYUHBB0ldKDBBtGQKKkMKijjKVRoZIC/TYqVBS48IOBsoQsTiGpCygM3vbJNoZglxABBQerkwRDi7ipiISrDbitccaj

我最初将它保存在 javascript 数组中，然后将其转换为 ArrayBuffer，然后将 ArrayBuffer 传递给 decodeAudioData()，在那里我遇到了错误

Error in promise : Unable to decode Audio Data

下面是代码：

function playByteArray(byteArray) {

    var arrayBuffer = new ArrayBuffer(byteArray.length);
    var bufferView = new Uint8Array(arrayBuffer);
    for (i = 0; i < byteArray.length; i++) {
      bufferView[i] = byteArray[i];
    }

    context.decodeAudioData(arrayBuffer, function(buffer) {
        buf = buffer;
        play();
    });
}

// Play the loaded file
function play() {
    // Create a source node from the buffer
    var source = context.createBufferSource();
    source.buffer = buf;
    // Connect to the final output node (the speakers)
    source.connect(context.destination);
    // Play immediately
    source.start(0);
}

提前感谢您的帮助。

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1 回答 1

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Your chunk of audio data probably isn't complete. In any case, you should consider using MediaSource Extensions for this task. That way, you can stream from the source and let the browser handle the rest.

于 2018-01-21T05:00:05.583 回答