- let marker (img: Image<Gray, byte>) (closed: Image<Gray, byte>) (level: float) : Image<Gray, byte> =
- let diff = closed - (img * level)
+ let marker (img: Image<Gray, float32>) (closed: Image<Gray, float32>) (level: float) : Image<Gray, byte> =
+ let diff = img.Copy() // closed - (img * level)
+ diff._Mul(level)
+ CvInvoke.Subtract(closed, diff, diff)