IGetFrame::Begin

The Begin method prepares to extract and decompress copies of frames from a stream. Called when an application uses the AVIStreamGetFrameOpen function.

HRESULT Begin(
  PAVISTREAM ps,  
  LONG lStart,    
  LONG lEnd,      
  LONG lRate      
);

Parameters

ps

Pointer to the interface to a stream.

lStart

Starting frame for extracting and decompressing.

lEnd

Ending frame for extracting and decompressing.

lRate

Speed at which the file is read relative to its normal playback rate. Normal speed is 1000. Larger values indicate faster speeds; smaller values indicate slower speeds.

Return Values

Returns the HRESULT defined by OLE.

Remarks

For handlers written in C++, Begin has the following syntax:

HRESULT Begin(LONG lStart, LONG lEnd, LONG lRate); 
 

Requirements

**  Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
**  Windows 95/98/Me:** Included in Windows 95 and later.
**  Header:** Declared in Vfw.h.
**  Library:** Use Vfw32.lib.

See Also

Custom File and Stream Handlers, Custom File and Stream Handler Interfaces, AVIStreamGetFrameOpen