hey there, +1
we did a facade mapping last year using 2 fullHD projectors, the video was something like 1920x2160 (with and without sound). As there was slightly sticky playback in resolume ith DXV and my collegues were not satisfied, I tried playing a mp4-file with Visution Mapio which worked out well.
We then sent the video stream from Mapio to Resolume via Syphon and the playback was still running smoothly!
(BTW: With Mapio we could also multiply the rendering resolution from 1920x2160 to 3840x4360 for smoother antialiasing)
AFAIK Mapio is using FFmpeg under the GNU LGPLv2.1, avcodec version: 57.48.101
QtAV library under the GNU LGPLv2.1, so it can also run DXV on the GPU. I don't know if they had this last year already, but the playback is always very smooth and not limited to DXV. Would maybe be an interesting update for Resolume