WriteableBitmap imageSource = new WriteableBitmap(videoWidth, videoHeight, 
 DPI_X, DPI_Y, System.Windows.Media.PixelFormats.Bgr32, null); 
... 
int rgbSize = width * height * 4; // bgr32 
IntPtr rgbPtr = Marshal.AllocHGlobal(rgbSize); 
YV12ToRgb(yv12Ptr, rgbPtr, width, height); 
// 更新图像 
imageSource.Lock(); 
Interop.Memcpy(this.imageSource.BackBuffer, rgbPtr, rgbSize); 
imageSource.AddDirtyRect(this.imageSourceRect); 
imageSource.Unlock(); 
Marshal.FreeHGlobal(rgbPtr); 

private VideoMixingRenderer9 CreateRenderer() { 
 var result = new VideoMixingRenderer9(); 
 var cfg = result as IVMRFilterConfig9; 
 cfg.SetNumberOfStreams(1); 
 cfg.SetRenderingMode(VMR9Mode.Renderless); 
 var notify = result as IVMRSurfaceAllocatorNotify9; 
 var allocator = new Vmr9Allocator(); 
 notify.AdviseSurfaceAllocator(m_userId, allocator); 
 allocator.AdviseNotify(notify); 
 // 在构建VMR9 Render时，注册新视频帧渲染完成事件 
 allocator.NewAllocatorFrame += new Action(allocator_NewAllocatorFrame); 
 // 注册接收新D3DSurface被创建的事件 
 allocator.NewAllocatorSurface += new NewAllocatorSurfaceDelegate(allocator_NewAllocatorSurface); 
 return result; 
 } 
 void allocator_NewAllocatorSurface(object sender, IntPtr pSurface) 
 { 
  // 为了方便理解，只保留核心部分。省略改写了其他部分 
  ... 
  // 将pSurface设置为D3DImage的BackBuffer 
  this.m_d3dImage.Lock(); 
  this.m_d3dImage.SetBackBuffer(D3DResourceType.IDirect3DSurface9, pSurface); 
  this.m_d3dImage.Unlock(); 
  ... 
 } 
 void allocator_NewAllocatorFrame() 
 { 
  ... 
  // 重绘 
  this.m_d3dImage.Lock(); 
  this.m_d3dImage.AddDirtyRect(new Int32Rect(0, /* Left */ 
    0, /* Top */ 
    this.m_d3dImage.PixelWidth, /* Width */ 
    this.m_d3dImage.PixelHeight /* Height */)); 
  this.m_d3dImage.Unlock(); 
  ... 
 } 

public void StretchRectangle( 
 Surface sourceSurface, 
 Rectangle sourceRectangle, 
 Surface destSurface, 
 Rectangle destRectangle, 
 TextureFilter filter 
); 

public void Render(IntPtr imgBuffer) 
{ 
 lock (this.renderLock) 
 { 
  // 将图像数据填充进offscreen surface 
  this.FillBuffer(imgBuffer); 
  // 调用StrentchRectangle把原始图像数据Copy到TextureSurface中         
  this.StretchSurface(); 
  // 执行渲染操作 
  this.CreateScene(); 
 } 
 // 通知D3DImage刷新图像 
 this.InvalidateImage(); 
}