StretchDIBits function (wingdi.h)
The StretchDIBits function copies the color data for a rectangle of pixels in a DIB, JPEG, or PNG image to the specified destination rectangle. If the destination rectangle is larger than the source rectangle, this function stretches the rows and columns of color data to fit the destination rectangle. If the destination rectangle is smaller than the source rectangle, this function compresses the rows and columns by using the specified raster operation.
int StretchDIBits( [in] HDC hdc, [in] int xDest, [in] int yDest, [in] int DestWidth, [in] int DestHeight, [in] int xSrc, [in] int ySrc, [in] int SrcWidth, [in] int SrcHeight, [in] const VOID *lpBits, [in] const BITMAPINFO *lpbmi, [in] UINT iUsage, [in] DWORD rop );
A handle to the destination device context.
The x-coordinate, in logical units, of the upper-left corner of the destination rectangle.
The y-coordinate, in logical units, of the upper-left corner of the destination rectangle.
The width, in logical units, of the destination rectangle.
The height, in logical units, of the destination rectangle.
The x-coordinate, in pixels, of the source rectangle in the image.
The y-coordinate, in pixels, of the source rectangle in the image.
The width, in pixels, of the source rectangle in the image.
The height, in pixels, of the source rectangle in the image.
A pointer to the image bits, which are stored as an array of bytes. For more information, see the Remarks section.
A pointer to a BITMAPINFO structure that contains information about the DIB.
Specifies whether the bmiColors member of the BITMAPINFO structure was provided and, if so, whether bmiColors contains explicit red, green, blue (RGB) values or indexes. The iUsage parameter must be one of the following values.
||The array contains 16-bit indexes into the logical palette of the source device context.|
||The color table contains literal RGB values.|
For more information, see the Remarks section.
A raster-operation code that specifies how the source pixels, the destination device context's current brush, and the destination pixels are to be combined to form the new image. For a list of some common raster operation codes, see BitBlt.
If the function succeeds, the return value is the number of scan lines copied. Note that this value can be negative for mirrored content.
If the function fails, or no scan lines are copied, the return value is 0.
If the driver cannot support the JPEG or PNG file image passed to StretchDIBits, the function will fail and return GDI_ERROR. If failure does occur, the application must fall back on its own JPEG or PNG support to decompress the image into a bitmap, and then pass the bitmap to StretchDIBits.
The origin of a bottom-up DIB is the lower-left corner; the origin of a top-down DIB is the upper-left corner.
StretchDIBits creates a mirror image of a bitmap if the signs of the nSrcWidth and nDestWidth parameters, or if the nSrcHeight and nDestHeight parameters differ. If nSrcWidth and nDestWidth have different signs, the function creates a mirror image of the bitmap along the x-axis. If nSrcHeight and nDestHeight have different signs, the function creates a mirror image of the bitmap along the y-axis.
StretchDIBits creates a top-down image if the sign of the biHeight member of the BITMAPINFOHEADER structure for the DIB is negative. For a code example, see Sizing a JPEG or PNG Image.
This function allows a JPEG or PNG image to be passed as the source image. How each parameter is used remains the same, except:
- If the biCompression member of BITMAPINFOHEADER is BI_JPEG or BI_PNG, lpBits points to a buffer containing a JPEG or PNG image, respectively. The biSizeImage member of the BITMAPINFOHEADER structure specifies the size of the buffer. The iUsage parameter must be set to DIB_RGB_COLORS. The dwRop parameter must be set to SRCCOPY.
- To ensure proper metafile spooling while printing, applications must call the CHECKJPEGFORMAT or CHECKPNGFORMAT escape to verify that the printer recognizes the JPEG or PNG image, respectively, before calling StretchDIBits.
For an example, see Sizing a JPEG or PNG Image.
|Minimum supported client||Windows 2000 Professional [desktop apps only]|
|Minimum supported server||Windows 2000 Server [desktop apps only]|
|Header||wingdi.h (include Windows.h)|