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ICDrawBegin

The ICDrawBegin function initializes the renderer and prepares the drawing destination for drawing.

DWORD ICDrawBegin(
  HIC hic,                  
  DWORD dwFlags,            
  HPALETTE hpal,            
  HWND hwnd,                
  HDC hdc,                  
  int xDst,                 
  int yDst,                 
  int dxDst,                
  int dyDst,                
  LPBITMAPINFOHEADER lpbi,  
  int xSrc,                 
  int ySrc,                 
  int dxSrc,                
  int dySrc,                
  DWORD dwRate,             
  DWORD dwScale             
);

Parameters

hic

Handle to the decompressor to use.

dwFlags

Decompression flags. The following values are defined.

Value Meaning
ICDRAW_ANIMATE Application can animate the palette.
ICDRAW_CONTINUE Drawing is a continuation of the previous frame.
ICDRAW_FULLSCREEN Draws the decompressed data on the full screen.
ICDRAW_HDC Draws the decompressed data to a window or a DC.
ICDRAW_MEMORYDC DC is off-screen.
ICDRAW_QUERY Determines if the decompressor can decompress the data. The driver does not decompress the data.
ICDRAW_UPDATING Current frame is being updated rather than played.

hpal

Handle to the palette used for drawing.

hwnd

Handle to the window used for drawing.

hdc

DC used for drawing.

xDst

The x-coordinate of the upper right corner of the destination rectangle.

yDst

The y-coordinate of the upper right corner of the destination rectangle.

dxDst

Width of the destination rectangle.

dyDst

Height of the destination rectangle.

lpbi

Pointer to a BITMAPINFO structure containing the format of the input data to be decompressed.

xSrc

The x-coordinate of the upper right corner of the source rectangle.

ySrc

The y-coordinate of the upper right corner of the source rectangle.

dxSrc

Width of the source rectangle.

dySrc

Height of the source rectangle.

dwRate

Frame rate numerator. The frame rate, in frames per second, is obtained by dividing dwRate by dwScale.

dwScale

Frame rate denominator. The frame rate, in frames per second, is obtained by dividing dwRate by dwScale.

Return Values

Returns ICERR_OK if the renderer can decompress the data or ICERR_UNSUPPORTED otherwise.

Remarks

The ICDRAW_HDC and ICDRAW_FULLSCREEN flags are mutually exclusive. If an application sets the ICDRAW_HDC flag in dwFlags, the decompressor uses hwnd, hdc, and the parameters defining the destination rectangle (xDst, yDst, dxDst, and dyDst). Your application should set these parameters to the size of the destination rectangle. Specify destination rectangle values relative to the current window or DC.

If an application sets the ICDRAW_FULLSCREEN flag in dwFlags, the hwnd and hdc parameters are not used and should be set to NULL. Also, the destination rectangle is not used and its parameters can be set to zero.

The source rectangle is relative to the full video frame. The portion of the video frame specified by the source rectangle is stretched or shrunk to fit the destination rectangle.

The dwRate and dwScale parameters specify the decompression rate. The integer value specified for dwRate divided by the integer value specified for dwScale defines the frame rate in frames per second. This value is used by the renderer when it is responsible for timing frames during playback.

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

Video Compression Manager, Video Compression Functions, BITMAPINFO