{"date":"2026-09-26","reviewer":"Codex visual review; no independent human review","scope":"64 selected source timestamps and both actual exports (128 output frames), in five windows across four scenarios. Other scenarios have playable evidence and export checks, not exhaustive face labels.","selection":"Diagnostic zero-mask intervals and motion overview images were used to select windows. This is failure analysis, not a random accuracy sample.","frameIndex":"Zero-based at 24 fps; start inclusive, end exclusive; crops use original 1280×720 coordinates [left,top,right,bottom].","extraction":"FFmpeg selects decoded frames by integer frame index. Contact sheets crop the same rectangle from source and both actual exports; no detector rerendering.","criterion":"Covered means all visible facial features are obscured. Missing or partial masks count as missed. Hair/back-of-head with no face is ineligible. Ambiguous fragments are uncertain. Only the main subject in each selected crop is scored; background false positives are not exhaustively annotated.","windows":[{"clip":"head-turns","startFrame":72,"endFrameExclusive":88,"crop":[500,0,1000,450],"frames":[{"frame":72,"fast":"covered","thorough":"covered"},{"frame":73,"fast":"covered","thorough":"covered"},{"frame":74,"fast":"covered","thorough":"covered"},{"frame":75,"fast":"uncertain","thorough":"uncertain"},{"frame":76,"fast":"ineligible","thorough":"ineligible"},{"frame":77,"fast":"ineligible","thorough":"ineligible"},{"frame":78,"fast":"ineligible","thorough":"ineligible"},{"frame":79,"fast":"ineligible","thorough":"ineligible"},{"frame":80,"fast":"ineligible","thorough":"ineligible"},{"frame":81,"fast":"ineligible","thorough":"ineligible"},{"frame":82,"fast":"ineligible","thorough":"ineligible"},{"frame":83,"fast":"ineligible","thorough":"ineligible"},{"frame":84,"fast":"missed","thorough":"missed"},{"frame":85,"fast":"covered","thorough":"covered"},{"frame":86,"fast":"covered","thorough":"covered"},{"frame":87,"fast":"covered","thorough":"covered"}]},{"clip":"party","startFrame":0,"endFrameExclusive":8,"crop":[150,0,1100,720],"frames":[{"frame":0,"fast":"missed","thorough":"covered"},{"frame":1,"fast":"covered","thorough":"covered"},{"frame":2,"fast":"covered","thorough":"covered"},{"frame":3,"fast":"covered","thorough":"covered"},{"frame":4,"fast":"covered","thorough":"covered"},{"frame":5,"fast":"covered","thorough":"covered"},{"frame":6,"fast":"covered","thorough":"covered"},{"frame":7,"fast":"covered","thorough":"covered"}]},{"clip":"party","startFrame":58,"endFrameExclusive":78,"crop":[150,0,1100,720],"frames":[{"frame":58,"fast":"missed","thorough":"covered"},{"frame":59,"fast":"missed","thorough":"covered"},{"frame":60,"fast":"missed","thorough":"covered"},{"frame":61,"fast":"missed","thorough":"covered"},{"frame":62,"fast":"missed","thorough":"covered"},{"frame":63,"fast":"missed","thorough":"covered"},{"frame":64,"fast":"missed","thorough":"covered"},{"frame":65,"fast":"missed","thorough":"covered"},{"frame":66,"fast":"covered","thorough":"covered"},{"frame":67,"fast":"covered","thorough":"covered"},{"frame":68,"fast":"covered","thorough":"covered"},{"frame":69,"fast":"covered","thorough":"covered"},{"frame":70,"fast":"missed","thorough":"covered"},{"frame":71,"fast":"missed","thorough":"covered"},{"frame":72,"fast":"missed","thorough":"covered"},{"frame":73,"fast":"missed","thorough":"covered"},{"frame":74,"fast":"missed","thorough":"covered"},{"frame":75,"fast":"covered","thorough":"covered"},{"frame":76,"fast":"covered","thorough":"covered"},{"frame":77,"fast":"covered","thorough":"covered"}]},{"clip":"party-2x","startFrame":28,"endFrameExclusive":40,"crop":[150,0,1100,720],"frames":[{"frame":28,"fast":"covered","thorough":"covered"},{"frame":29,"fast":"covered","thorough":"covered"},{"frame":30,"fast":"missed","thorough":"covered"},{"frame":31,"fast":"missed","thorough":"covered"},{"frame":32,"fast":"covered","thorough":"covered"},{"frame":33,"fast":"covered","thorough":"covered"},{"frame":34,"fast":"missed","thorough":"covered"},{"frame":35,"fast":"missed","thorough":"covered"},{"frame":36,"fast":"missed","thorough":"covered"},{"frame":37,"fast":"missed","thorough":"covered"},{"frame":38,"fast":"covered","thorough":"covered"},{"frame":39,"fast":"covered","thorough":"covered"}]},{"clip":"breakdance","startFrame":112,"endFrameExclusive":120,"crop":[480,150,850,450],"frames":[{"frame":112,"fast":"ineligible","thorough":"ineligible"},{"frame":113,"fast":"uncertain","thorough":"uncertain"},{"frame":114,"fast":"uncertain","thorough":"uncertain"},{"frame":115,"fast":"uncertain","thorough":"uncertain"},{"frame":116,"fast":"covered","thorough":"covered"},{"frame":117,"fast":"covered","thorough":"covered"},{"frame":118,"fast":"covered","thorough":"covered"},{"frame":119,"fast":"covered","thorough":"covered"}]}],"findings":[{"clip":"party","mode":"fast","startFrame":58,"endFrameExclusive":66,"confirmedUncoveredFrames":8,"durationSeconds":0.3333333333333333,"recoveredFrame":66,"otherMode":"thorough","otherModeCovered":true,"description":"Clear face throughout head roll; Fast has no mask on eight consecutive frames. Thorough covers the face. This is a confirmed interval, not the longest failure in the full corpus."},{"clip":"party","mode":"fast","startFrame":70,"endFrameExclusive":75,"confirmedUncoveredFrames":5,"durationSeconds":0.20833333333333334,"recoveredFrame":75,"otherMode":"thorough","otherModeCovered":true,"description":"A second face-visible gap. Fast recovers at frame 75."},{"clip":"party","mode":"fast","startFrame":0,"endFrameExclusive":1,"confirmedUncoveredFrames":1,"durationSeconds":0.041666666666666664,"recoveredFrame":1,"otherMode":"thorough","otherModeCovered":true,"description":"Cold-start miss on the first frame."},{"clip":"head-turns","mode":"both","startFrame":84,"endFrameExclusive":85,"confirmedUncoveredFrames":1,"durationSeconds":0.041666666666666664,"recoveredFrame":85,"description":"Partial profile with visible nose and mouth reappears through hair. Fast has no mask; Thorough masks the torso instead. Both cover the face on the next three reviewed frames."},{"clip":"party-2x","mode":"fast","startFrame":30,"endFrameExclusive":32,"confirmedUncoveredFrames":2,"durationSeconds":0.08333333333333333,"recoveredFrame":32,"otherMode":"thorough","otherModeCovered":true,"description":"Lagging mask leaves an eye and other facial features visible despite a nonzero mask count."},{"clip":"party-2x","mode":"fast","startFrame":34,"endFrameExclusive":38,"confirmedUncoveredFrames":4,"durationSeconds":0.16666666666666666,"recoveredFrame":38,"otherMode":"thorough","otherModeCovered":true,"description":"Partial coverage on frames 34–35, then no mask on frames 36–37. Thorough covers all four."}],"publicParagraphs":["Fast missed eight consecutive face-visible frames during the close-up head roll, from 2.417 to 2.750 seconds (end exclusive). Thorough covered that interval. Fast also missed five frames from 2.917 to 3.125 seconds.","Both modes missed the reappearing face at 3.500 seconds in the head-turn clip and covered it again at 3.542 seconds. Thorough placed a mask on the torso instead of the face in the missed frame.","At 2× speed, Fast also produced lagging masks that left facial features visible. A nonzero mask count is not proof of face coverage. These selected failures do not establish a complete ranking across all motion scenarios."],"evidenceFiles":["window-breakdance-112-115.jpg","window-breakdance-116-119.jpg","window-head-turns-072-075.jpg","window-head-turns-076-079.jpg","window-head-turns-080-083.jpg","window-head-turns-084-087.jpg","window-party-000-003.jpg","window-party-004-007.jpg","window-party-058-061.jpg","window-party-062-065.jpg","window-party-066-069.jpg","window-party-070-073.jpg","window-party-074-077.jpg","window-party-2x-028-031.jpg","window-party-2x-032-035.jpg","window-party-2x-036-039.jpg"],"observations":["The joggers are a back-of-head control, not a face-coverage success. Sampled output shows unnecessary masking, especially in Fast.","Both modes also mask painted background faces in the choreography sample.","Mask inflation/lag appears during turns; full pixel review matters in addition to detector traces."],"limitations":["No overall motion coverage percentage.","These are correlated short stock excerpts, including three synthetic 2× variants.","Neither re-identification resistance nor demographic fairness is measured.","No claim that unreviewed frames or cases pass face coverage."]}