using AForge;
using AForge.Controls;
using AForge.Video;
using AForge.Video.DirectShow;
using Size = System.Drawing.Size;

FilterInfoCollection videoDevices;
videoDevices = new FilterInfoCollection(FilterCategory.VideoInputDevice);

foreach (FilterInfo device in videoDevices)
{
  //可以做出处理
}

FileterInfo info;
info = videoDevices[0];//选取第一个,此处可作灵活改动

VideoCaptureDevice videoSource = new VideoCaptureDevice(videoDevices[info.MonikerString);
videoSource.DesiredFrameSize = new System.Drawing.Size(214, 281);
videoSource.DesiredFrameRate = 1;

videoSourcePlayer.VideoSource = videoSource;
videoSourcePlayer.Start();

videoSourcePlayer.SignalToStop();
videoSourcePlayer.WaitForStop();

if (videoSourcePlayer.IsRunning)
{
　　string path = "e:\"
  BitmapSource bitmapSource = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(
  videoSourcePlayer.GetCurrentVideoFrame().GetHbitmap(),
  IntPtr.Zero,
  Int32Rect.Empty,
  BitmapSizeOptions.FromEmptyOptions());
  PngBitmapEncoder pE = new PngBitmapEncoder();
  pE.Frames.Add(BitmapFrame.Create(bitmapSource));
  string picName = path + "paizhao" + ".jpg";
  if (File.Exists(picName))
  {
 File.Delete(picName);
  }
  using (Stream stream = File.Create(picName))
  {
 pE.Save(stream);
  }
}

BitmapImage bmi = new System.Windows.Media.Imaging.BitmapImage();

bmi.BgeinInit();

bmi.UriSource = new Uri(picName);

bmi.CacheOption = BitmapCacheOption.OnLoad;

bmi.EndInit();

this.image.Source = bmi;