Forward-chaining each accumulated burst onto the previous one suppresses
arrival jitter, but an unchecked chain never recovers: one lost datagram, or a
declared sampling rate that differs from the producer's real one, dates every
later sample early for the rest of the run. The chain is now a prediction,
compared each packet against the arrival anchor and abandoned beyond
kBurstResyncThresholdS, which bounds the error instead of accumulating it.
Plan amended so the hrt-fit fallback (unusable here: the fit needs 32 packets
and is itself corrupted by bursty arrivals) cannot come back.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Implements FrameDecoder with five timing rules that mirror
UDPSourceSession.cpp: FullArray (per-element time signal), FirstSample
and LastSample (rate-spread from anchor), accumulated scalar with
declared rate (forward-chain anchoring, immune to arrival jitter), and
PACKET burst (backward-span from previous arrival). 9 new tests, 38
pass total.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
The fit keeps the slope and discards the intercept, so the result counts from
the producer's boot. Tasks 4 and 7 compose it with ClockOffset::map, which is
correct, but the bare name invites passing it straight to a plot axis.
Also unwrapped the stalled-clock assertion from behind `if (fit.ready())` —
that branch never runs, so the test confirmed nothing.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
The jitter test fed a receive timestamp that went backwards (1001.02 then
1000.97), putting the second reading 1.03 s from the prediction — twice the
threshold, so not jitter under any reading. That is a digit slip for 1001.97.
It had been worked around by making the threshold one-sided, which passes the
test but never fires when the producer's clock steps forward: the prediction
stays ahead of the wall clock, the error stays negative, and the trace sits in
the future for the rest of the run. Restored std::fabs, corrected the test data,
and added the forward-jump case that the one-sided version silently failed.
Plan amended so the bad data does not come back.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Adds TimeBase.h/cpp with ClockOffset (latched wall-clock offset with
one-sided recalibration on positive drift only, so early-arriving packets
do not wobble the trace) and HrtRateFit (sliding-window OLS that recovers
an unknown hrt tick rate from receive timestamps). Also adds
TimeSignalScale() which maps UDPS type codes to seconds-per-count.
9 new tests, all 28 pass.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Gap 1: closeLeaf was only tested closing the first sibling; added test
closing the second sibling to cover the else branch of parent->a.get()==leaf.
The test verifies the correct sibling survives with its signal intact.
Gap 2: closeLeaf was only tested at depth 1 (root's direct children);
added test with depth-2 leaf (in right subtree) to exercise findParent's
recursive search in both subtrees. Tests that the correct leaf is promoted
and remaining signals are preserved.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
The ramp data in EmitsPointsInTimeOrder never produced a bucket whose maximum
preceded its minimum, so an implementation ordering the emitted pair by value
instead of by time would have passed. Replaced with an explicit two-bucket case
whose second bucket reverses the order.
file(COPY) is a hard configure error on a missing source, so a checkout without
the sibling StreamHub resources failed to configure despite the ASCII-icon
fallback the block above had just selected.
Plan amended to match on both points.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
