/// <summary>
/// Converts a GDI+ image to a Device Independent Bitmap.
/// </summary>
/// <param name="image">The image that shall be converted</param>
/// <param name="bitmapInfoPointer">Pointer to the BitmapInfo Structure of the Dib</param>
/// <param name="bitmapBitsPointer">Pointer to the pixel of the Dib</param>
public static void ImageToDib(
Image image,
ref IntPtr bitmapInfoPointer,
ref IntPtr bitmapBitsPointer)
{
if (image!=null)
{
//Get device context and bitmap handle
IntPtr compatibleDC=CreateCompatibleDC(IntPtr.Zero);
IntPtr bitmapHandle=new System.Drawing.Bitmap(image).GetHbitmap();
//Receive BitmapInfo from image
BitmapInfo bitmapInfo=new BitmapInfo();
bitmapInfoPointer=Marshal.AllocHGlobal(Marshal.SizeOf(bitmapInfo));
Marshal.StructureToPtr(
bitmapInfo,
bitmapInfoPointer, true);
Gdi32.GetDIBits(
compatibleDC,
bitmapHandle,
0,
0,
IntPtr.Zero,
bitmapInfoPointer,
ColorUse.DibRGBColors);
Marshal.PtrToStructure(
bitmapInfoPointer,
bitmapInfo);
//Allocate memory for the bitmapbits and receive them
Int32 s=((((bitmapInfo.bmiHeader.biWidth*bitmapInfo.bmiHeader.biBitCount)+31)/32)*4)*
System.Math.Abs(bitmapInfo.bmiHeader.biHeight);
bitmapBitsPointer=Marshal.AllocHGlobal(bitmapInfo.bmiHeader.biSizeImage+1024);
Gdi32.GetDIBits(
compatibleDC,
bitmapHandle,
0,
(uint)image.Height,
bitmapBitsPointer,
bitmapInfoPointer,
ColorUse.DibRGBColors);
//Tidy up
Gdi32.DeleteObject(bitmapHandle);
Gdi32.DeleteDC(compatibleDC);
}
}
public static extern Int32 GetDIBits(
IntPtr DeviceContext,
IntPtr BitmapHandle,
uint StartScanLine,
uint ScanLines,
IntPtr BitmapBits,
ref BitmapInfo bmi,
ColorUse Usage);