VC++2008编写的winform应用程序中lockbit方法问题

Question

在使用VC++2008编写的winform应用程序中，添加了一个PictureBox控件，使用lockbits等方法实现某些功能后，图像还原不过去了，也就是实现不了想要的方法，下面是实现把彩色图像灰化的代码。请改正，谢谢。

Bitmap^ image1 = gcnew Bitmap(this->OriginalPicture->Image);
                             Rectangle rect = Rectangle(0, 0, image1->Width, image1->Height);
              System::Drawing::Imaging::BitmapData^ bmpData =
                    image1->LockBits(rect, System::Drawing::Imaging::ImageLockMode::ReadWrite,
                    image1->PixelFormat);
                      IntPtr ptr = bmpData->Scan0;

                     int bytes = image1->Width * image1->Height*3;
    array<Byte>^rgbValues = gcnew array<Byte>(bytes);
    System::Runtime::InteropServices::Marshal::Copy(ptr, rgbValues,0, bytes);
       Console::WriteLine(rgbValues->Length);
     for(int count=0;count<rgbValues->Length ;count+=3)
    {
      int k=System::Convert ::ToInt32(rgbValues[count]* 0.299+rgbValues[count+1]*0.587+rgbValues[count+2]*0.114);
      rgbValues[count]=k;
      rgbValues[count+1]=k;
      rgbValues[count+2]=k;

    }

     System::Runtime::InteropServices::Marshal::Copy(rgbValues , 0, ptr, bytes);

                    image1->UnlockBits(bmpData);

                this->ResultPicture->Image = image1;