I’ve found a way to combine Iris and Artemis to upscale any standard definition source for realtime viewing on Apple TV, using my Mac Studio M1 Max and Mac mini M4 Pro in parallel. I found that the key is to use the NUT file container which fully supports simultaneous write and read by the two ffmpegs (on Macs) and VLC (Apple TV) across the network. No faffing around trying and failing to get streaming to work properly.
The reason for starting with Iris 1x is that Iris 2x is much too slow on Macs. Iris 1x does a nice job and also deals with the deinterlacing of MKVs from DVDs, feeding Artemis directly with the required progressive video. And because I’m using Macs, there is no processing cost to using ProRes for the Iris 1x output. So Star Trek DS9 and Voyager are now looking gorgeous on the TV with the Iris and Artemis combination - and in real time using a base spec Mac Studio and Mac mini M4 Pro. The only caveat is that I needed to slightly crop the height from 576 to 528 to get at least 25 fps. After experimenting, a Y offset of 28 gives the best result, allowing for the overlay credits to be nicely positioned.
In case anyone is interested, here are example ffmpeg commands:
Mac Studio M1 Max (or my MacBook Air M2):
ffmpeg -y -hide_banner -i “/Volumes/EXT2TB/DS9 DVDs/S1E06 Q-Less.mkv” -sws_flags spline+accurate_rnd+full_chroma_int -filter_complex “bwdif=mode=0:parity=-1:deint=0,crop=w=720:h=528:x=0:y=28,tvai_up=model=iris-3:scale=0:w=720:h=528:preblur=0:noise=0:details=0:halo=0:blur=0:compression=0:estimate=8:blend=0.5:device=0:vram=0.1:instances=1” -c:v prores_videotoolbox -profile:v standard -pix_fmt p210le -allow_sw 1 -c:a copy -f: nut /users/andy/intermediate.nut
Mac mini M4 Pro:
ffmpeg -y -hide_banner -i /Volumes/Andy/intermediate.nut -sws_flags spline+accurate_rnd+full_chroma_int -filter_complex “tvai_up=model=alq-13:scale=0:w=1440:h=1056:blend=0.5:device=0:vram=0.1:instances=1,scale=w=1440:h=1056:flags=lanczos:threads=0” -c:v hevc_videotoolbox -profile:v main -tag:v hevc -pix_fmt yuv420p -allow_sw 1 -g 30 -b:v 0 -q:v 82 -c:a copy -movflags frag_keyframe+empty_moov+delay_moov+use_metadata_tags+write_colr -bf 0 “/Users/andy/Desktop/Upscaled.nut”
On Apple TV, I use VLC to start playing “Upscaled.nut” from the Mac mini on the network just a few seconds after running its ffmpeg command.
Andy
