Stop serving a stale video frame as if the stream were live - #107
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This was referenced Jul 29, 2026
leandropineda
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get_frame_jpg() re-encoded the last decoded frame for as long as the stream stayed down, so the platform kept showing a frozen image that looked live -- the worst failure mode for a safety camera, and one that hides the outage from whoever is watching. Frames older than the new stale_frame_seconds (default 3s, ~3x the age a frame reaches at the default publish rate) are not served, so the platform shows no video instead. Pass stale_frame_seconds=None for the previous behaviour. Tests: 1 new case in test_video.py.
A fixed 3s window is wrong for a slow rate: at one frame every 10s a
3s-old frame is perfectly normal, so every frame would be withheld and
video would stop entirely.
The window now defaults to three publish periods -- 1s at 10 fps, 3s at 1
fps (unchanged from before), 30s at 0.1 fps -- with a 1s floor so a fast
rate does not withhold frames on ordinary jitter. An explicit
stale_frame_seconds still wins, and float("inf") disables the check.
Tests: 1 new case, 1 updated in test_video.py.
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A stale frame is dropped silently, so an operator sees the video stop with nothing saying why. Debug level because this is reached on every publish for as long as the stream stays down; the per-minute capture health line carries the count for normal operation.
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Stacked on #106.
get_frame_jpg()re-encoded the last decoded frame for as long as the stream stayed down, so the platform kept showing a frozen image that looked live — the worst failure mode for a safety camera, and it hides the outage from whoever is watching.Frames older than the new
stale_frame_seconds(default 3s, ~3× the age a frame reaches at the default publish rate) are no longer served, so the platform shows no video instead.stale_frame_seconds=Nonerestores the old behaviour.Behaviour change worth calling out in release notes.
Tests: 1 new case. Suite green, flake8/black clean.