From his February 2015 blog:
"In the meantime, I played with the popular VLC media player, which has a handy sharpen filter. It works very well. You can even toggle it during playback to easily see how well it works. If you want to save a lot of bandwidth on a 4K TV, just play a regular HEVC-encoded HD video upscaled 200% and sharpen it. When I saw how good it was, I understood why nobody cares about TRUDEF."