The WM_CAP_SET_CALLBACK_WAVESTREAM message sets a callback function in the application. AVICap calls this procedure during streaming capture when a new audio buffer becomes available. You can send this message explicitly or by using the capSetCallbackOnWaveStream macro.
WM_CAP_SET_CALLBACK_WAVESTREAM
wParam = (WPARAM) 0;
lParam = (LPARAM) (LPVOID) (fpProc);
Returns TRUE if successful or FALSE if streaming capture or a single-frame capture session is in progress.
The capture window calls the procedure before writing the audio buffer to disk. This allows applications to modify the audio buffer if desired.
If a wave stream callback function is used, it must be installed before starting the capture session and it must remain enabled for the duration of the session. It can be disabled after streaming capture ends.
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Unsupported.
Header: Declared in vfw.h.
Video Capture Overview, Video Capture Messages, capSetCallbackOnWaveStream