marfrit
e293078d46
Reference image of the bug as visible on ohm. Captured 2026-05-08 via mpv --hwdec=v4l2request --vo=dmabuf-wayland --pause --start=00:00:00.42 --fullscreen fourier-test/bbb_1080p30_h264.mp4 then spectacle -b -f -n. Uniform dark green at approx RGB(0, 75, 0) — exactly what the all-zero NV12 hypothesis (Y=U=V=0 through BT.601/709 conversion) predicts and what marfrit/dmabuf-modifier-triage#1 diagnoses (KWin reads past-EOF on the UV plane fd, returns zeros for chroma). Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
1021 B
Screenshots
Reference captures of the user-visible bug. Filed alongside phase0_findings.md so future readers see the symptom directly without reproducing it.
frame10_dmabuf_green.png
mpv --hwdec=v4l2request --vo=dmabuf-wayland --pause --start=00:00:00.42 --fullscreen fourier-test/bbb_1080p30_h264.mp4 on ohm, frame ~10 of bbb_1080p30_h264.mp4 (24 fps), captured via spectacle -b -f -n 2026-05-08.
Shows uniform dark green fill where the bbb test pattern should be. Black bars top/bottom are letterboxing from fullscreen presentation on PineTab2's 1280×800 display vs the 1920×1080 / 16:9 source — they're not part of the bug.
The dark green color is approximately RGB(0, 75, 0), which matches the predicted output of an all-zero NV12 buffer (Y=0, U=0, V=0) through BT.601/709 → RGB conversion. Confirms the marfrit/dmabuf-modifier-triage#1 diagnosis: KWin reads UV plane past-EOF on its fd 42, gets zeros, renders dark green.