Extensions: how to extend OMX_COLOR_FORMAT


I’m trying to find a way to declare a new vendor color format in OpenMax IL 1.1.2. I know it is possible to add such color format by using an extension (A region is reserved for introducing new Vendor Extensions).
But how to proceed if we want to register a new vendor specific color format in OMX_COLOR_FORMATTYPE enum.
First question: is possible to submit vendor specific color format?
If yes, I’m conscious that such adoption process may take time and require proposal notes, but any tips on how to proceed is welcome?

Thanks & Regards,