我正在使用Speex对原始数据进行编码,但在对数据进行解码后,音频以更快的速度播放,因为它会让您听起来像花栗鼠.我正在使用
NSpeex和Silverlight 4.
8kHz采样
编码功能：
JSpeexEnc encoder = new JSpeexEnc();
int rawDataSize = 0;
public byte[] EncodeAudio(byte[] rawData)
{
var encoder = new SpeexEncoder(BandMode.Narrow);
var inDataSize = rawData.Length / 2;
var inData = new short[inDataSize];
for (var index = 0; index < rawData.Length; index += 2)
{
inData[index / 2] = BitConverter.ToInt16(rawData,index);
}
inDataSize = inDataSize - inDataSize % encoder.FrameSize;
var encodedData = new byte[rawData.Length];
var encodedBytes = encoder.Encode(inData,inDataSize,encodedData,encodedData.Length);
byte[] encodedAudioData = null;
if (encodedBytes != 0)
{
encodedAudioData = new byte[encodedBytes];
Array.Copy(encodedData,encodedAudioData,encodedBytes);
}
rawDataSize = inDataSize; // Count of encoded shorts,for debugging
return encodedAudioData;
}
解码功能：
SpeexDecoder decoder = new SpeexDecoder(BandMode.Narrow);
public byte[] Decode(byte[] encodedData)
{
try
{
short[] decodedFrame = new short[8000]; // should be the same number of samples as on the capturing side
int decoderBytes = decoder.Decode(encodedData,encodedData.Length,decodedFrame,false);
byte[] decodedData = new byte[encodedData.Length];
byte[] decodedAudioData = null;
decodedAudioData = new byte[decoderBytes * 2];
for (int shortIndex = 0,byteIndex = 0; byteIndex < decoderBytes; shortIndex++)
{
BitConverter.GetBytes(decodedFrame[shortIndex + byteIndex]).CopyTo(decodedAudioData,byteIndex * 2);
byteIndex++;
}
// todo: do something with the decoded data
return decodedAudioData;
}
catch (Exception ex)
{
ShowMessageBox(ex.Message.ToString());
return null;
}
}
播放音频：
void PlayWave(byte[] PCMBytes)
{
byte[] decodedBuffer = Decode(PCMBytes);
MemoryStream ms_PCM = new MemoryStream(decodedBuffer);
MemoryStream ms_Wave = new MemoryStream();
_pcm.SavePcmToWav(ms_PCM,ms_Wave,16,8000,1);
WaveMediaStreamSource WaveStream = new WaveMediaStreamSource(ms_Wave);
mediaElement1.SetSource(WaveStream);
mediaElement1.Play();
}
解决方法
对于迟到的回应抱歉,但我弄清楚问题是什么.
在我的解码函数中,我遍历解码的短数组,但我只是将一半的字节复制到我的新字节数组中.
它需要看起来像这样：
decodedAudioData = new byte[decoderBytes * 2]; for (int shortIndex = 0,byteIndex = 0; shortIndex < decodedFrame.Length; shortIndex++,byteIndex += 2) { byte[] temp = BitConverter.GetBytes(decodedFrame[shortIndex]); decodedAudioData[byteIndex] = temp[0]; decodedAudioData[byteIndex + 1] = temp[1]; }