android - 如何将 short[] 转换为 double[]？

Question

现在，我正在处理一个音频信号，我想实时显示我用手机录制的音频声波。

这是一个问题，我的音频格式是“ENCODING_PCM_16BIT”。那么如何将 16 位短数据转换为 double 格式呢？

这是我的代码，但它不能正常工作。谁能帮我解决这个问题？

try {

        AudioRecord audioRecord = new AudioRecord(MediaRecorder.AudioSource.MIC, Sample_rate, Channel, Encording,
                Buffersize);

        DataOutputStream dos = new DataOutputStream(
                new BufferedOutputStream(new FileOutputStream(MainActivity.file)));

        short[] buffer = new short[Buffersize / 2]; //870 double/ 2 = 435 double
        System.out.println("The buffer size is " + Buffersize);
        timer1();
        audioRecord.startRecording(); // Start record
        while (MainActivity.isrecord) {
            int bufferReadResult = audioRecord.read(buffer, 0, buffer.length);
            System.out.println("The buffer size is " + bufferReadResult);
            for (int i = 0; i < bufferReadResult/2; i++) {
                dos.writeShort(buffer[i]);
                **tempraw[i] = (double)buffer[i];**
            }
            phase = DataProcess(tempraw);
        }
        audioRecord.stop(); // record stop
        audioRecord.release();
        audioRecord = null;
        dos.close(); // Output stream close
        dos = null;
    } catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

我想把那些数据放在“short[] buffer”到“double[] tempraw”

谢谢!

在我从网上看了一些代码后，我做了这个。我认为它有效，只是很慢，一个 double 需要 2 毫秒

private static double shorttodouble(short[] a, int index) {
    // TODO Auto-generated method stub
    long l;
    l = a[index + 0];
    l &= 0xffff;
    l |= ((long) a[index + 1] << 16);
    l &= 0xffffffffl;
    l |= ((long) a[index + 2] << 32);
    l &= 0xffffffffffffl; 
    l |= ((long) a[index + 3] << 48);
    l &= 0xffffffffffffffffl; 
    l |= ((long) a[index + 4] << 64);
    return (double)l;
}

Answer 1

试试这个:---

 short[] buffer = new short[size];
    double[] transformed = new double[buffer.length];
    for (int j=0;j<buffer.length;j++) {
    transformed[j] = (double)buffer[j];
    }