Most efficent way to cast PNG images to a Roku device?

Hi,

I would like to cast my MacBook display to my Roku TV but AirPlay isn't supported so I created my own Roku app and MacOS client for this purpose. The Roku app polls a PNG screenshot image served over HTTP by the MacOS client and it works however there is significant lag, around 2-3 seconds. Would it be faster to do this with a live HLS stream?

Thanks!