static void OverrideFindBestFormat (GLib.GType gtype, FindBestFormatNativeDelegate callback)
		{
			unsafe {
				IntPtr* raw_ptr = (IntPtr*)(((long) gtype.GetClassPtr()) + (long) class_abi.GetFieldOffset("find_best_format"));
				*raw_ptr = Marshal.GetFunctionPointerForDelegate((Delegate) callback);
			}
		}
		private void InternalFindBestFormat (Gst.Caps downstream_caps, Gst.Video.VideoInfo best_info, bool at_least_one_alpha)
		{
			FindBestFormatNativeDelegate unmanaged = null;
			unsafe {
				IntPtr* raw_ptr = (IntPtr*)(((long) this.LookupGType().GetThresholdType().GetClassPtr()) + (long) class_abi.GetFieldOffset("find_best_format"));
				unmanaged = (FindBestFormatNativeDelegate) Marshal.GetDelegateForFunctionPointer(*raw_ptr, typeof(FindBestFormatNativeDelegate));
			}
			if (unmanaged == null) return;

			unmanaged (this.Handle, downstream_caps == null ? IntPtr.Zero : downstream_caps.Handle, best_info == null ? IntPtr.Zero : best_info.Handle, at_least_one_alpha);
		}