GDI32Api、Direct3D屏幕截圖

最近因為工作需要，認真研究了一下屏幕截圖的方法。

最主要的方法有兩種，一、調用windows GDI32 API函數。二、使用DirectX9.0來實現。

另外，光注了一下Microsoft Expression Encoder 4 Screen Capture這個微軟新出的功能，Expression　Encoder 4 可實現屏幕錄制，錄制 文件格式為WMV ，為免費使用版本，Expression Encoder 4 Pro為 收費版本。

還 看了一下基於windows圖形驅動技術的屏幕截圖方法 ，文章鏈接地址： http://blog.csdn.net/jia162/article/details/2509974。實現起來可能比較困難與復雜。沒找到實例參考及技術實現的算法，因此也就沒有深入研究。

下面兩種方法

一、GDI32 API截圖， 600*480大小生成Bitmap位圖大概需要45ms左右，生成位圖並save成bmp文件需要大概110ms左右，圖片越大，耗費的時間越長，效率比較低。

二、DirectX截圖，是把整個屏幕的拷貝到內存里，再進行截取，執行拷貝屏幕的方法g_pd3dDevice->GetFrontBufferData(0, g_pSurface) 需要80ms-100ms，效率也比較低。

若那位技術牛人有好滴方法，請推薦一下哦！！！

方法一實現：

 

 

 
           using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Runtime.InteropServices;
 
 namespace DataFrameFetch
 {
     public class WinGdi32Api
     {
         [DllImport("GDI32.dll")]
         public static extern bool BitBlt(int hdcDest, int nXDest, int nYDest, int nWidth, int nHeight, int hdcSrc, int nXSrc, int nYSrc, int dwRop);
         [DllImport("GDI32.dll")]
         public static extern int CreateCompatibleBitmap(int hdc, int nWidth, int nHeight);
         [DllImport("GDI32.dll")]
         public static extern int CreateCompatibleDC(int hdc);
         [DllImport("GDI32.dll")]
         public static extern bool DeleteDC(int hdc);
         [DllImport("GDI32.dll")]
         public static extern bool DeleteObject(int hObject);
         [DllImport("GDI32.dll")]
         public static extern int GetDeviceCaps(int hdc, int nIndex);
         [DllImport("GDI32.dll")]
         public static extern int SelectObject(int hdc, int hgdiobj);
         [DllImport("User32.dll")]
         public static extern int GetDesktopWindow();
         [DllImport("User32.dll")]
         public static extern int GetWindowDC(int hWnd);
         [DllImport("User32.dll")]
         public static extern int GetDC(int hWnd);
         [DllImport("User32.dll")]
         public static extern int ReleaseDC(int hWnd, int hDC);
     }
 }
 
 
  
 
  
 
 using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Windows.Forms;
 using System.Runtime.InteropServices;
 using System.Drawing;
 using System.Drawing.Imaging;
 using System.IO;
 
 
 namespace DataFrameFetch
 {
     public class DataFetch
     {
 
         public DataFetch()
         { }
 
     
 
         /// <summary>
         /// 全屏截圖
         /// </summary>
         /// <returns></returns>
         public Bitmap CaptureScreen()
         {
             DateTime dt_start = DateTime.Now;
             int source = WinGdi32Api.GetWindowDC(WinGdi32Api.GetDesktopWindow());
             int bitmap = WinGdi32Api.CreateCompatibleBitmap(source, WinGdi32Api.GetDeviceCaps(source, 8), WinGdi32Api.GetDeviceCaps(source, 10));
 
             int destination = WinGdi32Api.CreateCompatibleDC(source);
             WinGdi32Api.SelectObject(destination, bitmap);
             WinGdi32Api.BitBlt(destination, 0, 0, WinGdi32Api.GetDeviceCaps(source, 8), WinGdi32Api.GetDeviceCaps(source, 10), source, 0, 0, 0x00CC0020);
             Bitmap img = this.GetBitmap(bitmap);
             this.Cleanup(bitmap, source, destination);
             DateTime dt_end = DateTime.Now;
             TimeSpan ts = dt_end - dt_start;   
             System.Diagnostics.Debug.WriteLine(ts.Milliseconds.ToString());
             return img;
         }
 
         public Bitmap CaptureScreen(Control control)
         {
             DateTime dt_start = DateTime.Now;
 
             int source = WinGdi32Api.GetDC(control.Handle.ToInt32());
             int bitmap = WinGdi32Api.CreateCompatibleBitmap(source, control.Width,control.Height);
 
             int destination = WinGdi32Api.CreateCompatibleDC(source);
             WinGdi32Api.SelectObject(destination, bitmap);
             WinGdi32Api.BitBlt(destination, 0, 0, control.Width, control.Height, source, 0, 0, 0x00CC0020);
             Bitmap img = this.GetBitmap(bitmap);
             this.Cleanup(bitmap, source, destination);
 
             byte[] buffer = this.ConvertBitmapToRGBByteArray(img);
 
             string filename = "F:\\img\\" + dt_start.ToString("yyyyMMddHHmmss") + dt_start.Millisecond.ToString();
 
             FileStream fs = new FileStream(filename + ".olc", FileMode.Create);
             fs.Write(buffer, 0, buffer.Length);
             fs.Flush();
             fs.Close();
 
             //Bitmap bmp = this.FromRGB(buffer, img.Width, img.Height);
             //bmp.Save(filename + "_1.bmp");
 
             DateTime dt_end = DateTime.Now;
             TimeSpan ts = dt_end - dt_start;
             System.Diagnostics.Debug.WriteLine(ts.Milliseconds.ToString());
             return img;
         }
 
         private void Cleanup(int bitmap, int source, int destination)
         {
             WinGdi32Api.ReleaseDC(WinGdi32Api.GetDesktopWindow(), source);
             WinGdi32Api.DeleteDC(destination);
             WinGdi32Api.DeleteObject(bitmap);
         }
 
         private Bitmap GetBitmap(int hbitmap)
         {
             Bitmap bmp = new Bitmap(Image.FromHbitmap(new IntPtr(hbitmap)), Image.FromHbitmap(new IntPtr(hbitmap)).Width, Image.FromHbitmap(new IntPtr(hbitmap)).Height);
             return bmp;
         }       
 
         /// <summary>
         /// 將位圖轉換成數組
         /// </summary>
         /// <param name="bmp"></param>
         /// <returns></returns>
         private byte[] ConvertBitmapToRGBByteArray(Bitmap bmp)
         {
             Rectangle rect = new Rectangle(new Point(0,0),bmp.Size);
             BitmapData bmpdata = bmp.LockBits(rect, ImageLockMode.ReadWrite, PixelFormat.Format24bppRgb);
 
             int len = bmp.Width * bmp.Height * 3;
             byte[] buffer = new byte[len];
             int index = 0;
             unsafe
             {
                 byte* color = (byte*)bmpdata.Scan0;
                 for (int y = 0; y < bmp.Height; y++)
                 {
                     for (int x = 0; x < bmp.Width; x++)
                     {
                         buffer[index++] = *color;
                         buffer[index++] = *(color + 1);
                         buffer[index++] = *(color + 2);
                         color += 3;
                     }
                     //color += bmpdata.Stride - bmpdata.Width * 3;
                 }
             }
             bmp.UnlockBits(bmpdata);
             return buffer;
         }
 
  
 
         /// <summary>
         /// 圖像象素數組轉成位圖
         /// </summary>
         /// <param name="buffer"></param>
         /// <param name="width"></param>
         /// <param name="height"></param>
         /// <returns></returns>
         public Bitmap ConvertRGBByteArrayToBitmap(byte[] buffer, int width, int height)
         {
             // 申請目標位圖的變量，並將其內存區域鎖定 
             Bitmap bmp = new Bitmap(width, height, PixelFormat.Format24bppRgb);//創建新圖像 
             Rectangle rect = new Rectangle(0, 0, width, height);
             BitmapData bmpData = bmp.LockBits(rect,ImageLockMode.WriteOnly,PixelFormat.Format24bppRgb);
             //// 用Marshal的Copy方法，將剛才得到的內存字節數組復制到BitmapData中 
             Marshal.Copy(buffer, 0, bmpData.Scan0, buffer.Length);
             bmp.UnlockBits(bmpData);  // 解鎖內存區域 
   
             return bmp;
         }
     }
 } 
          

 

方法二以VC++實現

 

            BOOL ScreenShot(HWND hWnd, TCHAR* fileName) 
           
 { 
           
    HRESULT hr; 
           
 
           
     
           
    IDirect3D9*   gpD3D=NULL; 
           
    IDirect3DDevice9* gpd3dDevice=NULL; 
           
    IDirect3DSurface9* gpSurface=NULL; 
           
 
           
 D3DDISPLAYMODE ddm; 
           
 D3DPRESENT_PARAMETERS d3dpp; 
           
 
           
  
           if((gpD3D=Direct3DCreate9(D3D_SDK_VERSION))==NULL)
 {
  ErrorMessage("Unable to Create Direct3D ");
  return E_FAIL;
 }

 if(FAILED(gpD3D->GetAdapterDisplayMode(D3DADAPTER_DEFAULT,&ddm)))
 {
  ErrorMessage("Unable to Get Adapter Display Mode");
  return E_FAIL;
 } 

 ZeroMemory(&d3dpp,sizeof(D3DPRESENT_PARAMETERS));

 d3dpp.Windowed=WINDOW_MODE;
 d3dpp.Flags=D3DPRESENTFLAG_LOCKABLE_BACKBUFFER;
 d3dpp.BackBufferFormat=ddm.Format;
 d3dpp.BackBufferHeight=nDisplayHeight=gScreenRect.bottom =ddm.Height;
 d3dpp.BackBufferWidth=nDisplayWidth=gScreenRect.right =ddm.Width;
 d3dpp.MultiSampleType=D3DMULTISAMPLE_NONE;
 d3dpp.SwapEffect=D3DSWAPEFFECT_DISCARD;
 d3dpp.hDeviceWindow=hWnd;
 d3dpp.PresentationInterval=D3DPRESENT_INTERVAL_DEFAULT;
 d3dpp.FullScreen_RefreshRateInHz=D3DPRESENT_RATE_DEFAULT;

 if(FAILED(gpD3D->CreateDevice(D3DADAPTER_DEFAULT,D3DDEVTYPE_HAL,hWnd,D3DCREATE_SOFTWARE_VERTEXPROCESSING ,&d3dpp,&gpd3dDevice)))
 {
  ErrorMessage("Unable to Create Device");
  return E_FAIL;
 }

 if(FAILED(gpd3dDevice->CreateOffscreenPlainSurface(ddm.Width, ddm.Height, D3DFMT_A8R8G8B8, D3DPOOL_SCRATCH, &gpSurface, NULL)))
 {
  ErrorMessage("Unable to Create Surface");
  return E_FAIL;
 }
  if (FAILED(hr = gpd3dDevice->GetFrontBufferData(0, gpSurface))) 
    {
        gpSurface->Release() ;
        return hr ;
    }
 hr = D3DXSaveSurfaceToFile(fileName, D3DXIFF_BMP, gpSurface, NULL, NULL); 
    gpSurface->Release() ; 

   return hr ;
 }