Calculating the Duration of a WAV Sound
[The feature associated with this page, DirectSound, is a legacy feature. It has been superseded by WASAPI and Audio Graphs. Media Casting have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use Media Casting instead of DirectSound, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]
The length of time for which a waveform will play is determined by the data size and the format.
The following example function returns the duration of a WAV file, in milliseconds:
DWORD GetSoundLength(LPSTR strFileName)
{
CWaveFile* pWav;
DWORD dwLen = 0;
DWORD dwSize;
WAVEFORMATEX* wfx;
pWav = new CWaveFile();
if (SUCCEEDED(pWav->Open(strFileName, NULL, WAVEFILE_READ)))
{
wfx = pWav->GetFormat();
dwSize = pWav->GetSize();
dwLen = (DWORD) (1000 * dwSize / wfx->nAvgBytesPerSec);
pWav->Close();
}
if (pWav) delete pWav;
return dwLen;
}