Component with System.Drawing.Bitmap input?

Hello how to read System.Drawing.Bitmap from genereic parameter and use it?

pManager.AddGenericParameter("Bitmap", "B", "", GH_ParamAccess.item);
protected override void SolveInstance(IGH_DataAccess DA)
            // First, we need to retrieve all data from the input parameters.
            // We'll start by declaring variables and assigning them starting values.

            object img = null; // The bitmap declared as object

After testing the component, the image type is:

img.GetType().ToString() ===> Grasshopper.Kernel.Types.GH_ObjectWrapper