code: public void setImage(I image, D derivX, D derivY) {
  		InputSanityCheck.checkSameShape(image, derivX, derivY);
  
  		this.image = image;
  		this.interpInput.setImage(image);
  
  		this.derivX = derivX;
  		this.derivY = derivY;
  	}
docs: Sets the current image it should be tracking with.
  
  @param image  Original input image.
  @param derivX Image derivative along the x-axis
  @param derivY Image derivative along the y-axis