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c#-如何正确地将16Bit字节数组转换为音频片段数据?

(c# - How to convert 16Bit byte array to audio clip data correctly?)

发布于 2020-11-26 13:26:24

我与Media Foundataion合作,我需要做的是将声音样本帧从字节转换为音频浮动数据。为了做到这一点,我使用了这种方法(我在Google的某个地方找到了):

    private static float[] Convert16BitByteArrayToAudioClipData(byte[] source, int headerOffset, int dataSize)
    {
        int wavSize = BitConverter.ToInt32(source, headerOffset);
        headerOffset += sizeof(int);
        Debug.AssertFormat(wavSize > 0 && wavSize == dataSize, "Failed to get valid 16-bit wav size: {0} from data bytes: {1} at offset: {2}", wavSize, dataSize, headerOffset);

        int x = sizeof(Int16); // block size = 2
        int convertedSize = wavSize / x;

        float[] data = new float[convertedSize];

        Int16 maxValue = Int16.MaxValue;
        int i = 0;

        while (i < convertedSize)
        {
            int offset = i * x + headerOffset;
            data[i] = (float)BitConverter.ToInt16(source, offset) / maxValue;
            ++i;
        }

        Debug.AssertFormat(data.Length == convertedSize, "AudioClip .wav data is wrong size: {0} == {1}", data.Length, convertedSize);

        return data;
    }

我这样使用它:

...
byte[] source = ...; // lenght 43776

... = Convert16BitByteArrayToAudioClipData(source , 0, 0);
...

看起来这个方法工作不正确,因为如果我传递一个数组大小为43776的数组,结果是while在索引i = 21886偏移值处循环,offset = 43776它将导致此下一个方法的异常

data[i] = (float)BitConverter.ToInt16(source /*43776*/, offset /*43776*/) / maxValue;

因为此值不能相同。

问题是-如何解决此方法?或者,也许有人可以建议使用什么代替呢?

编辑

    private static float[] Convert16BitByteArrayToAudioClipData(byte[] source)
    {
        float[] data = new float[source.Length];

        for (int i = 0; i < source.Length; i++)
        {
            data[i] = (float) source[i];
        }

        return data;
    }
Questioner
Aleksey Timoshchenko
Viewed
11
Aleksey Timoshchenko 2020-12-01 23:11:15

最终,我以这种方式做到了:

    public static float[] Convert16BitByteArrayToAudioClipData(byte[] source)
    {
        int x = sizeof(Int16); 
        int convertedSize = source.Length / x;
        float[] data = new float[convertedSize];
        Int16 maxValue = Int16.MaxValue;

        for (int i = 0; i < convertedSize; i++)
        {
            int offset = i * x;
            data[i] = (float)BitConverter.ToInt16(source, offset) / maxValue;
            ++i;
        }

        return data;
    }