Possible? Probably. Take the output of the H.264 encoder used for Miracast and put it in an HTTP stream instead of (I believe, in the case of Miracast) an RTP stream. It would be similar to how the Chromecast tab casting works.
Since it's an HTTP stream you might be able to get away with not having cyclic intrablock refresh, allowing it to work on some devices that don't work with Miracast due to their H.264 encoders lacking required functions.
It would probably be a royal pain in the ass to implement in a reliable fashion though.