private static unsafe void FillBitmapInfo(ref Win32API.BITMAPINFO bmi, int width, int height, int bpp, int origin)
{
Debug.Assert(width > 0 && height > 0 && (bpp == 8 || bpp == 24 || bpp == 32));
Win32API.BITMAPINFOHEADER bmih = bmi.Header;
using (ScopedGCHandle handle = new ScopedGCHandle(bmih, GCHandleType.Pinned))
{
//Win32API.FillMemory(handle.AddrOfPinnedObject(), Marshal.SizeOf(typeof(Win32API.BITMAPINFOHEADER)), 0);
bmih.Size = (uint)sizeof(Win32API.BITMAPINFOHEADER);
bmih.Width = width;
bmih.Height = (origin != 0) ? Math.Abs(height) : -Math.Abs(height);
bmih.Planes = 1;
bmih.BitCount = (ushort)bpp;
bmih.Compression = Win32API.BI_RGB;
bmih.ClrImportant = 0;
bmih.Compression = 0;
bmih.SizeImage = 0;
bmih.XPelsPerMeter = 0;
bmih.YPelsPerMeter = 0;
bmi.Header = bmih;
}
if (bpp == 8)
{
Win32API.RGBQUAD[] palette = bmi.Colors;
for (int i = 0; i < palette.Length; i++)
{
palette[i].Blue = palette[i].Green = palette[i].Red = (byte)i;
palette[i].Reserved = 0;
}
bmi.Colors = palette;
}
}
/// <summary>
///
/// </summary>
/// <param name="img"></param>
/// <param name="hdc"></param>
/// <param name="dstRect"></param>
public static void DrawToHdc(this IplImage img, IntPtr hdc, CvRect dstRect)
{
if (Platform.OS == OS.Unix)
{
throw new PlatformNotSupportedException("This method is only for Windows.");
}
if (img == null)
{
throw new ArgumentNullException("img");
}
if (hdc == IntPtr.Zero)
{
throw new ArgumentNullException("hdc");
}
if (img.Depth != BitDepth.U8)
{
throw new NotSupportedException();
}
int bmpW = img.Width;
int bmpH = img.Height;
CvRect roi = Cv.GetImageROI(img);
unsafe
{
int headerSize = sizeof(Win32API.BITMAPINFOHEADER) + 1024;
IntPtr buffer = Marshal.AllocHGlobal(headerSize);
Win32API.BITMAPINFO bmi = (Win32API.BITMAPINFO)Marshal.PtrToStructure(buffer, typeof(Win32API.BITMAPINFO));
if (roi.Width == dstRect.Width && roi.Height == dstRect.Height)
{
DrawToHdc(img, hdc, dstRect.X, dstRect.Y, dstRect.Width, dstRect.Height, roi.X, roi.Y);
return;
}
if (roi.Width > dstRect.Width)
{
Win32API.SetStretchBltMode(hdc, Win32API.HALFTONE);
}
else
{
Win32API.SetStretchBltMode(hdc, Win32API.COLORONCOLOR);
}
FillBitmapInfo(ref bmi, bmpW, bmpH, img.Bpp, (int)img.Origin);
Win32API.StretchDIBits(
hdc,
dstRect.X, dstRect.Y, dstRect.Width, dstRect.Height,
roi.X, roi.Y, roi.Width, roi.Height,
img.ImageData, ref bmi, Win32API.DIB_RGB_COLORS, Win32API.SRCCOPY);
Marshal.FreeHGlobal(buffer);
}
}
/// <summary>
///
/// </summary>
/// <param name="img"></param>
/// <param name="hdc"></param>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="w"></param>
/// <param name="h"></param>
/// <param name="fromX"></param>
/// <param name="fromY"></param>
public static void DrawToHdc(this IplImage img, IntPtr hdc, int x, int y, int w, int h, int fromX, int fromY)
{
if (Platform.OS == OS.Unix)
{
throw new PlatformNotSupportedException("This method is only for Windows.");
}
if (img == null)
{
throw new ArgumentNullException("img");
}
if (hdc == IntPtr.Zero)
{
throw new ArgumentNullException("hdc");
}
if (img.Depth != BitDepth.U8)
{
throw new NotSupportedException();
}
int bmpW = img.Width;
int bmpH = img.Height;
unsafe
{
int headerSize = sizeof(Win32API.BITMAPINFOHEADER) + 1024;
IntPtr buffer = Marshal.AllocHGlobal(headerSize);
Win32API.BITMAPINFO bmi = (Win32API.BITMAPINFO)Marshal.PtrToStructure(buffer, typeof(Win32API.BITMAPINFO));
FillBitmapInfo(ref bmi, bmpW, bmpH, img.Bpp, (int)img.Origin);
fromX = Math.Min(Math.Max(fromX, 0), bmpW - 1);
fromY = Math.Min(Math.Max(fromY, 0), bmpH - 1);
uint sw = (uint)Math.Max(Math.Min(bmpW - fromX, w), 0);
uint sh = (uint)Math.Max(Math.Min(bmpH - fromY, h), 0);
Win32API.SetDIBitsToDevice(
hdc, x, y, sw, sh, fromX, fromY, (uint)fromY, sh,
new IntPtr(img.ImageData.ToInt32() + fromY * img.WidthStep),
ref bmi, Win32API.DIB_RGB_COLORS);
Marshal.FreeHGlobal(buffer);
}
}
