CopyFromScreen() question.

HDC								hdc = GetDC(0);
HDC								mdc = CreateCompatibleDC(hdc);
HBITMAP						hbmpscreen;
BITMAPINFO				bmi;
HGDIOBJ						obmp;

bmi.bmiHeader.biSize          = sizeof(BITMAPINFO);
bmi.bmiHeader.biWidth         = GetSystemMetrics(SM_CXSCREEN);
bmi.bmiHeader.biHeight        = GetSystemMetrics(SM_CYSCREEN);
bmi.bmiHeader.biPlanes        = 1; 
bmi.bmiHeader.biBitCount      = 24;
bmi.bmiHeader.biCompression   = 0; 
bmi.bmiHeader.biSizeImage     = (((bmi.bmiHeader.biWidth*bmi.bmiHeader.biBitCount/8)+3)&~3)*bmi.bmiHeader.biWidth;
bmi.bmiHeader.biXPelsPerMeter = 300;
bmi.bmiHeader.biYPelsPerMeter = 300;
bmi.bmiHeader.biClrUsed       = 0;
bmi.bmiHeader.biClrImportant  = 0;

hbmpscreen = CreateDIBitmap(mdc,&hbmpscreen,0,0,&bmi.bmiHeader,DIB_RGB_COLORS);
obmp = SelectObject(mdc,hbmpscreen);
BitBlt(mdc,0,0,bmi.bmiHeader.biWidth,bmi.bmiHeader.biHeight,hdc,0,0,SRCCOPY);

SelectObject(mdc,obmp);
DeleteDC(mdc);
ReleaseDC(hdc);