Converting Image

Mat -> System.Drawing.Bitmap

Mat mat = new Mat("foobar.jpg", ImreadModes.Color);

Bitmap bitmap = OpenCvSharp.Extensions.BitmapConverter.ToBitmap(mat);

System.Drawing.Bitmap -> Mat

Bitmap bitmap = new Bitmap("foobar.jpg");

Mat mat = OpenCvSharp.Extensions.BitmapConverter.ToMat(bitmap);

Mat -> byte[]

Mat mat = new Mat("foobar.jpg", ImreadModes.Color);

byte[] bytes1 = mat.ToBytes(".png");

byte[] bytes2;
Cv2.ImEncode(".jpg", mat, out bytes2);

byte[] -> Mat

byte[] imageData = System.IO.File.ReadAllBytes("foobar.jpg");

Mat colorMat = Mat.FromImageData(imageData, ImreadModes.Color);
Mat grayscaleMat = Mat.FromImageData(imageData, ImreadModes.GrayScale);

Mat alt = Cv2.ImDecode(imageData, ImreadModes.GrayScale);