C# 调用C++ DLL 参数Emgu.cv.Mat如何传递

Question

C++ 做了视频识别的DLL动态库，导出函数
extern "C" __declspec(dllexport)float Recognition(Mat frame,int type)；

C#主程序调用C++的视频识别动态库
[DllImport(@"Recognition.dll", EntryPoint = "Recognition", CallingConvention = CallingConvention.Cdecl)]
public extern static float Recognition(Mat frame, int iType);

    C#调用内容如下：
      Bitmap bmp = cameraControl1.TakeSnapshot();
  Image<Bgr, byte> image = new Image<Bgr, byte>(bmp);
  //Image<Bgr, byte>转Mat
  Mat mat = image.Mat;
  Mat Graymat = mat.Clone();
   float Value = Recognition(Graymat, 1);

        运行到float Value = Recognition( Graymat, 1);行，查看 Graymat 变量内容正常；
        按F11  调试到C++工程；查看传入的Mat 变量 frame 宽度、高度、数据均不正常；不知道原因，改成参数引用传递也不行。调试信息如图
        哪位大神急救下！
        ![图片说明](https://img-ask.csdn.net/upload/201908/20/1566271847_310078.png)![图片说明](https://img-ask.csdn.net/upload/201908/20/1566271855_169575.png)

Answer 1

C# 传递图像数组
[DllImport(@"Recognition.dll", EntryPoint = "Recognition", CallingConvention = CallingConvention.Cdecl)]
public extern static float Recognition(byte[] ImageBuffer, int imageWedth, int imageHeight, int imageStride, int iType);
图片转换成byte数组：

Bitmap bmp = cameraControl1.TakeSnapshot();
System.Drawing.Imaging.PixelFormat rgb = bmp.PixelFormat;
Rectangle rect = new Rectangle(0, 0, bmp.Width, bmp.Height);
System.Drawing.Imaging.BitmapData bmpData = bmp.LockBits(rect, System.Drawing.Imaging.ImageLockMode.ReadWrite, bmp.PixelFormat);

            // Get the address of the first line.
            IntPtr ptr = bmpData.Scan0;

            // Declare an array to hold the bytes of the bitmap. 
            int bytes = Math.Abs(bmpData.Stride) * bmp.Height;
            byte[] rgbValues = new byte[bytes];

            // Copy the RGB values into the array.
            System.Runtime.InteropServices.Marshal.Copy(ptr, rgbValues, 0, bytes);

            // Unlock the bits.
            bmp.UnlockBits(bmpData);
            int ImageWedth = bmp.Width;
            int ImageHeight = bmp.Height;
            int ImageStride = bmpData.Stride;
            Recognition(rgbValues, ImageWedth, ImageHeight, ImageStride,1);

                C++ 动态库修改：
                extern "C"  __declspec(dllexport)float  Recognition(byte *ImageBuffer, int imageWedth, int imageHeight, int imageStride,int type)

{

Mat frame = cv::Mat(imageHeight, imageWedth, CV_8UC4, ImageBuffer, imageStride);
...
}