音频PCM数据，单声道变双声道

int single2Double(char *pData, int nSize)
{unsigned short szBuf[4096];unsigned short *pst = (unsigned short*)pData;memset(szBuf, 0, sizeof(szBuf));memcpy(szBuf, pData, nSize);for (int i = 0; i < nSize; i++){if (i % 2 == 0) { pst[i] = szBuf[i / 2];}else {pst[i] = pst[i - 1]; } } return nSize * 2;
}