mirror of
https://git.k-space.ee/arti/vt1200.git
synced 2026-11-01 12:14:56 +02:00
arti
c5526332f0
Two knobs for the 60 fps attempt, both measured on Bad Apple: clip_from_video.py --block N averages each NxN block, thresholds the average and draws the block flat. The point is destination words: at 60 fps the clip changes 80 tiles/frame unstylised, 54 at 8x8 and 29 at 16x16, against the ~44-tile budget that MAME's ~3.4 us/word allows in 16.7 ms. A side effect worth knowing: with 16-pixel blocks every 32x32 tile is one of exactly 2^4 combinations, so the 256 entry dictionary represents the stylised clip with zero error (measured: 16 entries used, "reconstruction 0 bit(s)", PSNR inf, mean delta 141 B against 496 B for the unstylised clip). vidsend.py --keyframe-every N exposes the cadence that TileSender already had as a constructor argument. A keyframe repaints all 1,280 tiles (~264 ms of MAME CPU at the measured 0.22 ms/tile), so the default 60-frame cadence costs ~4.4 ms on average per frame at 60 fps -- a tenth of the budget spent on repairs. The 13,167-frame stylised clip ships 220 keyframes at the default; 600 measured 6 in the same window. Measured on the stylised 60 fps cache (13,167 frames, 16 dictionary entries): --fps 60, default cadence 643 of 805 accepted (80%), drops=8 --fps 45 484 of 520 accepted, drops=0, sender PASS --fps 60, --keyframe-every 600 451 of 519 accepted, drops=5 So the stylised clip roughly doubles acceptance against the same 60 fps send (40% -> 80%) but MAME still caps the clean rate around 36-45 fps.