Audited the engine for what it does when something goes wrong rather than
when it goes right. Each of these left the process healthy, the dashboard
green and the product not working.
A gallery the running encoder cannot read. Embeddings are model-tagged, so
when the fallback chain fires every vector the previous encoder wrote goes
invisible: the shop keeps its customer list and recognises nobody on it,
enrolling each regular a second time. Footfall stays correct, which is why
nothing looks wrong. The only evidence was an INFO line reading 'gallery
ready: 0 embeddings (model w600k_mbf) across 21 identities' - a sentence
that states the disaster and calls it ready. Gallery.health now warns with
the count of PEOPLE lost, not vectors, and carries the same numbers to
/api/stats and /api/health, because a log line on a shop PC is read by
nobody. Proved against the real 87-embedding gallery.
Connected, and sending nothing. 'connected' meant the socket opened, so a
stream that went quiet kept it true while last_frame_age_s climbed and the
heartbeat told head office the camera was up. OpenCV breaks a blocked read
at 30s, but a camera trickling a frame every 20s never trips that and never
recovers. streaming/stalled are reported beside connected and the dashboard
says live/stalled/offline - three states because offline sends you to the
network and stalled says the camera is answering and sending nothing.
The 5-second RTSP timeout that never existed. stimeout;5000000 carried a
comment claiming it bounded a dead camera. Measured on OpenCV 4.11 /
FFmpeg 7.1 against a socket that accepts and then says nothing: 30.0s with
stimeout, 30.0s with timeout, 30.3s with no option at all - identical, so
it was never honoured. stimeout became timeout in FFmpeg 5.0 and neither
reaches the RTSP protocol through this path; the real bound is OpenCV's own
interrupt constant. Replaced by the _tcp_reachable pre-flight probe_source
already used, in code we own: 30.3s -> 0.00-2.02s, each naming its cause.
That matters beyond speed - the VideoCapture constructor is not
interruptible, so stop() could not cut it short and a camera removed from
head office left a daemon thread holding a socket for half a minute.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KGcjxF1cNLcuwc3DAPcnfj
Brand assets in brand/ (the 512px mark, sizes for each surface, a
multi-size .ico). Windows executables carry it as a compiled-in
resource (rsrc_windows_amd64.syso from go-winres) so Explorer, the
taskbar and the installer show it; installer/build.ps1 therefore uses a
plain go build rather than wails build, which would add a second copy
and fail the link. The tray icon is the mark with a state dot over its
corner - a plain coloured circle read as a generic status light among
other icons - rendered from the embedded PNG at 32px so it survives
150% scaling. The desktop app's login, setup and sidebar marks, the
head-office web app's mark and favicon, and the engine dashboard's
favicon are the same file.
Also found while packaging: no wheel so far shipped static/, so the
engine's own dashboard at :8010 on a Windows source install would have
failed with a missing file. package-data now includes it.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KGcjxF1cNLcuwc3DAPcnfj
Five components that ship as one product:
- behavision/ the recognition engine. RTSP ingest, YuNet detection, IoU
tracking, ArcFace embeddings, a FAISS/SQLite gallery, and a
FastAPI dashboard. Identity is decided once per TRACK from an
average of at least three embeddings, never per frame.
- agent/ the Go edge agent: supervises the engine, holds a durable
spool, and drains it to MQTT. Nothing is acked before the
broker confirms.
- desktop/ the shop PC application (Wails + React + tray).
- server/ the cloud API, MQTT consumer, reports and assistant.
- web/ platform.loyaly.ai, the head-office app, embedded in the
server binary.
The gallery stores 512-float embeddings and timestamps - no images unless
`app.store_faces` is switched on. Those embeddings are biometric personal
data under GDPR and India's DPDP: template inversion reconstructs a
recognisable face from an ArcFace vector, so data/behavision.db is treated
as a biometric database and DELETE /api/visitors/{id} is a real erasure.
CLAUDE.md carries the reasoning behind every non-obvious decision here,
including the ones that were measured and the ones that were wrong first.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HViLj9gYNRtSr7YVZmW5sn
