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Detection from WebCam Capture using EmguCV

See original GitHub issue

Hello! Nice wrapper! I tried it over some existing images and worked well but I have a problem using it with capture from my laptop camera. EmguCV is processing the bitmaps well and detects my face without issues but ProcessImage always returns null. The wrapper is initializing properly. Marshal.GetLastWin32Error() returns error code 203. I’m converting the Capture frames from their bitmaps to byte arrays using LockBits. Will put some code samples below so you can test. I’m using the latest Emgu from NuGet version 3.1.0.1.

using (var imageFrame = this.capture.QueryFrame().ToImage<Bgr, Byte>())
            {
                if (imageFrame != null)
                {
                    CoreRectangleCandidate[] yoloObjects = this.yoloWrapper.ProcessImage(BitmapToByteArray(imageFrame.Bitmap));

                    int errorMessage = Marshal.GetLastWin32Error();

                    if (yoloObjects != null)
                    {
                        foreach (CoreRectangleCandidate rect in yoloObjects.Where(wr => wr.objectType == "person"))
                        {
                            imageFrame.Draw(new Rectangle(rect.rectangle.topLeftCorner.x, rect.rectangle.topLeftCorner.y, rect.rectangle.width, rect.rectangle.height),
                                new Bgr(Color.Wheat), 3);
                        }
                    }
}
}

public static byte[] BitmapToByteArray(Bitmap bitmap)
        {

            BitmapData bmpdata = null;

            try
            {
                bmpdata = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadOnly, bitmap.PixelFormat);
                int numbytes = bmpdata.Stride * bitmap.Height;
                byte[] bytedata = new byte[numbytes];
                IntPtr ptr = bmpdata.Scan0;

                Marshal.Copy(ptr, bytedata, 0, numbytes);

                return bytedata;
            }
            finally
            {
                if (bmpdata != null)
                    bitmap.UnlockBits(bmpdata);
            }

        }