网络流中的图像转化为OpenCV中的Mat类型

1，从网络中读取到的图像流，不支持查找，不能直接转化为Mat类型

2，例子如下：

string Url = "http://192.168.0.110/cgi-bin/camera?resolution=1920";                           //网络地址
            Stream stream = WebRequest.Create(Url).GetResponse().GetResponseStream();   //获取到网络流
            Bitmap bmp = new Bitmap(stream);                                                                             //从流中获取Bitmap
            MemoryStream ms = new MemoryStream();                                                               //申请内存流
            bmp.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);                                    //将获得到的Bitmap保存到内存流中（关键技术）
            Mat scr = Mat.FromStream(ms, ImreadModes.AnyColor);                                           //从内存流中获取Mat对象。