The SSIM gate compared frame i with frame i of the other file. Measured 2026-10-11 on two
installed outputs: -fps_mode cfr inserts a duplicate wherever a frame is dropped, so the whole
window sits at a constant -1 frame; the old sweep stepped by 10 (it could never see +-1) and its
max(0, off) seek made every NEGATIVE offset identical to 0. Cost: 14 items refused in 9.6 h
(12.4 h of lane time, then parked) while healthy encodes read 0.9808/0.9862 instead of
0.9976/0.9974.
* alignment: fine step-1 +-6 -> coarse step-10 +-100 -> per-frame +-2 best match, each stage named
in the verdict, PID-tagged temp files (two lanes share the stage dir), pair stats logs pruned
* the alignment note is INFORMATION now: it used to arrive in the irregular-timeline slot, which
skips the whole picture verdict - the canary and two x265 items were accepted that way with the
mean bar never enforced
* a window decode that fails is retried once and its ffmpeg stderr is kept (a transient decode
killed a finished 16.7-minute encode with a bare 'no frames compared'); gate decodes get their
own 60-minute stall window because trim writes nothing before the window starts; the ssim filter
and the pair comparisons are time-bounded so a wedged ffmpeg cannot hang a lane
* bars (owner decision): mean 0.995, redo/owner-released 0.990
* VMAF, observe-only and reported as vmaf480 because the window is the 480x270 one the gate already
decoded (480p reads ~+2.4/+3.2 points above native on the item measured) - the evidence base for
a threshold is two items, so it accumulates instead of gating
hoelee
7d16fedea5