Update targeted ICASSP 2027 manuscript and results

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% Acceptance-target ICASSP 2027 draft grounded only in archived measurements.
% The official 2027 author kit should replace the 2026-compatible style assets
% before submission. Four technical pages plus an optional reference-only page.
% Uses the repository's ICASSP 2027 author kit.
% Four technical pages plus an optional reference-only page.
\documentclass{article}
\usepackage{spconf}
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\usepackage{amsmath,amssymb,graphicx,booktabs,multirow,hyperref,xcolor,float}
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\newcommand{\vect}[1]{\boldsymbol{#1}}
\newcommand{\G}{\mathrm{G}}
\newcommand{\A}{\mathrm{A}}
\newcommand{\V}{\mathrm{V}}
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\title{Does an Omni Model Know When the Wearer Will Speak?\\
A Causal Global--Local Audit of Egocentric Speech Anticipation}
\name{Authors withheld in this working draft}
\address{}
\name{Xin Wang, Dingtian Yan, Shengxiang Hu, Changdong Liu,
Xiaoju Dai, Li Zhang, and Guorun Chen}
\address{School of Computer Science, Example University, Shanghai, China}
\begin{document}
\ninept
\maketitle
\begin{abstract}
An egocentric conversational agent must anticipate the future speech of an
invisible camera wearer from a causal multiparty audio--video stream. We ask
whether a frozen general-purpose Omni state exposes the sub-second evidence
needed by this task. Our cutoff-aligned model combines an 8-s Qwen2.5-Omni
context with the most recent 1-s audio and predicts three activity channels at
ten horizons from 0.2 to 2.0~s. In a single-seed EasyCom screen, this model reaches
81.72\% mAP at 0.2~s and 65.11\% averaged over horizons, compared with
74.20\% and 61.19\% for released EgoSpeak. The gain is larger for wearer
offset anticipation (+7.23 points) than onset anticipation (+1.47). Pooled
visual features add only 0.29 mean-mAP points. A separate three-seed,
strictly causal information audit explains this gap: privileged past activity
of visible participants adds 4.83 points at 0.2~s and 1.77 mean-mAP points,
whereas visibility, one-second-delayed activity, and identity shuffling show
that timeliness matters more than identity continuity. The results isolate an
evidence-access bottleneck: recent acoustic evidence is already useful, while
current generic visual pooling does not recover the available visible-floor
signal.
We test whether a frozen Omni readout exposes sub-second evidence for
forecasting an invisible camera wearer's speech from causal multiparty
audio--video. Our 5-Hz model combines 8-s Qwen2.5-Omni context and recent
1-s audio to predict three activity channels at ten 0.2--2.0-s horizons.
On EasyCom, a seed-0 screen reaches 81.72\% mAP at 0.2~s and 65.11\%
mean mAP, versus 74.20/61.19\% for released EgoSpeak. Wearer offset AP
improves by 7.23 points, onset AP by 1.47. Pooled vision adds only 0.29
mean-mAP points. A three-seed causal information audit finds that privileged
past visible-person activity adds 4.83 points at 0.2~s and 1.77 mean-mAP
points; visibility and delayed activity add little. A separate no-box
full-frame screen reaches 82.38/65.54\%, but unmatched training and head
capacity prevent visual attribution. Timely evidence access, not semantic
floor understanding, remains the supported conclusion.
\end{abstract}
\begin{keywords}
@@ -51,8 +55,18 @@ Conversational agents must decide not only \emph{what} to say, but also
\emph{when} to participate. This decision is particularly asymmetric in an
egocentric stream: the camera wearer is normally invisible, yet the model must
forecast that wearer's behavior from mixed audio and observations of other
people. A useful predictor must update before a turn boundary is known and
must not use media from after its decision cutoff.
people. As Fig.~\ref{fig:task} illustrates, prediction precedes any known
turn boundary and excludes media after the decision cutoff.
\begin{figure}[H]
\centering
\includegraphics[width=\columnwidth]{figures/task_overview.pdf}
\caption{Task, not an observed event example. At each 5-Hz decision cutoff,
only the past audio--video prefix is input; ten future activity states are
targets. ENTRY-like and YIELD-like refer to wearer activity transitions,
not semantic floor ownership.}
\label{fig:task}
\end{figure}
Voice Activity Projection (VAP) casts turn taking as continuous prediction of
future activity \cite{ekstedt2022vap}. EgoSpeak brings this objective to
@@ -74,28 +88,22 @@ state $\G$ from explicit recent evidence $\A$ and optional $\V$, and treat
their value as an empirical question rather than assuming that a larger
backbone solves temporal access.
This paper makes three contributions. First, we formulate a strictly causal
global--local audit for invisible-wearer activity forecasting, with a common
5-Hz cutoff and ten future horizons. Second, we realize the audit with a
bounded Omni stream that combines completed history with a temporary observed
tail and a separate one-second audio path. Third, we distinguish deployable
feature gains from an analysis-only visible-activity oracle. This reveals a
specific negative result---generic pooled or current-frame person features do
not recover most of the available local-floor information---and identifies
timely activity estimation, rather than identity continuity, as the next
modeling target.
We contribute a cutoff-aligned global--local audit, a bounded Omni stream
with observed-tail refresh and recent audio, and a separation of deployable
features from an analysis-only visible-activity oracle. Generic pooled or
current-frame person features recover little of the available activity signal;
timely activity estimation is the next modeling target.
\begin{figure*}[t]
\begin{figure}[t]
\centering
\includegraphics[width=0.97\textwidth]{figures/system_overview.pdf}
\caption{Global--local causal audit. At each 200-ms cutoff, the prediction
path fuses an integrated Omni state with explicit recent audio and optional
person-crop vision. Completed 2-s blocks are reused while only the observed
partial tail is temporarily recomputed. The purple branch is a privileged
past-activity audit used to test information value; it is never a deployable
input and contains no future activity.}
\includegraphics[width=\columnwidth]{figures/system_overview_onecolumn.pdf}
\caption{Deployable global--local path and bounded stream. At each 200-ms
cutoff, the head fuses the frozen integrated Omni state with explicit recent
audio and optional pooled person-crop vision. Completed 2-s payloads are
reused; only the observed partial tail is temporarily recomputed. Privileged
past-activity audit labels are kept outside this graph and are not inputs.}
\label{fig:overview}
\end{figure*}
\end{figure}
\section{Method}
\label{sec:method}
@@ -137,16 +145,13 @@ is frozen-backbone adaptation rather than end-to-end training.
\subsection{Cutoff-Aligned Streaming}
The global stream uses source-aligned 2-s blocks and an 8-s maximum
presentation budget. After warm-up, three completed blocks and the observed
part of the current block are available; the exact span varies with block
phase. Completed modality payloads are reused when the bounded language-model
cache is rebuilt. At every cutoff, the incomplete current block is cropped at
$t_n$, appended to a temporary cache, and queried for $\vect g_n$. Neither
the temporary tail nor the query is committed. At a block boundary the
completed payload is committed once and a new tail begins. Sessions and
source discontinuities reset all caches. Thus the logical state is refreshed
at 5~Hz without backfilling a completed block into earlier rows.
Figure~\ref{fig:overview} uses source-aligned 2-s blocks under an 8-s
presentation cap. After warm-up, three completed blocks and the observed
current tail are available; span varies with block phase. Completed
modality payloads are reused. At each cutoff, the tail is cropped at $t_n$
and queried in a temporary cache, without committing it. Only completed
blocks are committed; session or source discontinuities reset caches. This
refreshes the logical state at 5~Hz without backfilling earlier rows.
\subsection{Visible-Activity Information Audit}
@@ -161,6 +166,148 @@ second, and (v) one OR-pooled aggregate-visible history. These conditions
never expose future activity, but their speech labels make them privileged
diagnostics, not deployable features or upper bounds.
\begin{table*}[t]
\caption{Measured EasyCom screens (\%). Panel A: deployable models; Panel B:
three-seed privileged past-activity audit, which is not deployable. Mean is
ten-horizon dense mAP; On/Off are raw wearer endpoint AP, not semantic events.
F3 is a no-box, two-frame causal full-frame screen; it and the historical
deployable rows are exploratory seed-0 runs with unmatched head/training
details. F1 has three seeds. Dashes are unavailable, not zero.}
\label{tab:main}
\centering
\normalsize
\renewcommand{\arraystretch}{0.87}
\setlength{\tabcolsep}{5.0pt}
\begin{tabular}{@{}lccccc@{}}
\toprule
Method & $\mathrm{mAP}_{.2}\uparrow$ & $\mathrm{WAP}_{.2}\uparrow$
& Mean$\uparrow$ & On$\uparrow$ & Off$\uparrow$ \\\\
\midrule
EgoSpeak MiniROADA A+V & 74.204 & 63.750 & 61.193 & 24.491 & 38.024 \\\\
Recent Qwen audio $\A$ & 79.692 & 84.100 & 60.508 & -- & -- \\\\
Omni global $\G$ & 73.446 & 77.867 & 60.849 & -- & -- \\\\
Omni $\G+\A$ & 81.723 & 85.066 & 65.109 & 25.960 & 45.251 \\\\
Omni $\G+\A+$pooled-$\V$ & 82.027 & 85.086
& 65.400 & 26.019 & 45.371 \\\\
No-box full-frame F3 & 82.380 & -- & 65.540 & -- & -- \\\\
Current-frame person set F1 & $81.777{\pm}0.156$ & --
& $64.951{\pm}0.095$ & -- & -- \\\\
Matched-width $\G$ (L2) & -- & -- & -- & -- & -- \\\\
Past-delayed $\A$ (L3) & -- & -- & -- & -- & -- \\\\
Current-state persistence (L4) & -- & -- & -- & -- & -- \\\\
\bottomrule
\end{tabular}
\par\smallskip
\emph{Panel B: privileged past-activity audit (mean $\pm$ sample SD).}\par\smallskip
\normalsize
\setlength{\tabcolsep}{3.2pt}
\begin{tabular}{@{}lccc@{}}
\toprule
Extra condition & $\mathrm{mAP}_{.2}$ & $\mathrm{WAP}_{.2}$ & Mean \\\\
\midrule
None (audio baseline) & $81.869{\pm}.049$ & $85.264{\pm}.110$ & $65.177{\pm}.058$ \\\\
Visibility only & $81.945{\pm}.098$ & $85.200{\pm}.144$ & $65.217{\pm}.048$ \\\\
Activity delayed 1 s & $81.951{\pm}.086$ & $85.270{\pm}.137$ & $65.341{\pm}.051$ \\\\
Shuffled person IDs & $85.917{\pm}.085$ & $85.577{\pm}.246$ & $66.460{\pm}.090$ \\\\
Per-person activity & $86.266{\pm}.182$ & $85.608{\pm}.220$ & $66.660{\pm}.135$ \\\\
Aggregate visible activity & $\mathbf{86.696{\pm}.085}$ & $\mathbf{85.836{\pm}.147}$
& $\mathbf{66.951{\pm}.022}$ \\\\
\bottomrule
\end{tabular}
\end{table*}
\begin{table*}[t]
\caption{Chunk and context audit. Panel A is an unmeasured matched T/C
matrix: each row pairs $\G$ and $\G+\A$ on common valid cutoffs. Panel B is
a separate exploratory seed-0 global-only screen (10 epochs, 8-s cap,
2-FPS video); its rows are not entries in Panel A. Dashes are pending.}
\label{tab:stream_context}
\centering\normalsize
\renewcommand{\arraystretch}{0.87}
\setlength{\tabcolsep}{4pt}
\begin{tabular}{@{}llccccc@{}}
\toprule
Group & Refresh / cap & $\G$ mAP & $\G+\A$ mAP & $\Delta$ mAP
& $\Delta$ On & $\Delta$ Off \\
\midrule
T & Completed-only, 8 s & -- & -- & -- & -- & -- \\
T & Observed-tail, 8 s & -- & -- & -- & -- & -- \\
\midrule
C & Tail-aware, 2 s & -- & -- & -- & -- & -- \\
C & Tail-aware, 4 s & -- & -- & -- & -- & -- \\
C & Tail-aware, 6 s & -- & -- & -- & -- & -- \\
C & Tail-aware, 8 s & -- & -- & -- & -- & -- \\
C & Tail-aware, 10 s & -- & -- & -- & -- & -- \\
C & Tail-aware, 12 s & -- & -- & -- & -- & -- \\
\bottomrule
\end{tabular}
\par\smallskip
\emph{Panel B: reported 200-ms chunk screen; dense mAP (\%).}\par\smallskip
\begin{tabular}{@{}lccc@{}}
\toprule
Global feature construction & 0.2-s mAP & Mean mAP & Processor calls \\
\midrule
Native 2-s completed hold & 59.62 & 55.19 & 9,539 \\
Non-native 200-ms commits & 67.05 & 57.84 & 95,453 \\
Completed blocks + observed tail & 70.85 & 59.17 & -- \\
\bottomrule
\end{tabular}
\end{table*}
\begin{table}[t]
\caption{B result slots: paired within-backbone local-audio gains (unmeasured).
MiniCPM requires a matched readout/refresh/history audit before comparison.}
\label{tab:backbone}
\centering\normalsize
\setlength{\tabcolsep}{3pt}
\begin{tabular}{@{}lccc@{}}
\toprule
Backbone & $\G$ & $\G+\A$ & $\Delta$ \\
\midrule
Qwen Omni 3B & -- & -- & -- \\
Qwen Omni 7B & -- & -- & -- \\
MiniCPM-o 4.5 & -- & -- & -- \\
\bottomrule
\end{tabular}
\end{table}
\begin{table}[t]
\caption{H result slots: predeclared activity slices (unmeasured). Report
positive/negative counts and per-session scores; AP is undefined for a
pure-negative slice, which instead uses calibrated FPR.}
\label{tab:hard_slices}
\centering\normalsize
\setlength{\tabcolsep}{2.5pt}
\begin{tabular}{@{}lccc@{}}
\toprule
Slice & $N_+/N_-$ & AP & FPR \\
\midrule
Wearer onset & -- & -- & -- \\
Wearer offset & -- & -- & -- \\
Other pause (negative) & -- & n/a & -- \\
Overlap (negative) & -- & n/a & -- \\
\bottomrule
\end{tabular}
\end{table}
\begin{table}[t]
\caption{S result slots: full-path cost on the same hardware (unmeasured).
Include I/O and block transitions; logical 5 Hz is not measured throughput.}
\label{tab:efficiency}
\centering\normalsize
\setlength{\tabcolsep}{3pt}
\begin{tabular}{@{}lccc@{}}
\toprule
Stage & P50 ms & P95 ms & Peak GB \\
\midrule
Completed block & -- & -- & -- \\
Observed tail & -- & -- & -- \\
Local path + head & -- & -- & -- \\
Full path & -- & -- & -- \\
\bottomrule
\end{tabular}
\end{table}
\section{Experiments}
\label{sec:experiments}
@@ -191,36 +338,16 @@ already sufficient. Because that screen used Session~12 model selection
whereas the historical pooled row did not, their difference is diagnostic,
not a matched causal attribution.
\textbf{Six pre-specified control families.}
We freeze six pending control families: (L) capacity and recency, (T) tail
refresh crossed with local audio, (C) six context caps, (B) paired backbone
transfer, (H/Q) error slices and timelines, and (S) full-path efficiency.
They share the official split and physical cutoffs; the 8-s T/C row reuses
one run. The source retains unmeasured hypotheses and falsifiers.
\section{Results}
\label{sec:results}
\begin{table*}[t]
\caption{EasyCom Sessions~1--3 results (\%). $\mathrm{mAP}_{.2}$ and
$\mathrm{WAP}_{.2}$ are dense 0.2-s metrics; Mean averages dense mAP over ten
horizons. On/Off are raw wearer endpoint AP, not semantic event scores.
Deployable rows are archived single-seed screens; $\pm$ is shown only for the
three-seed F1 screen. Dashes denote unavailable measurements.}
\label{tab:main}
\centering
\scriptsize
\setlength{\tabcolsep}{5.0pt}
\begin{tabular}{@{}lccccc@{}}
\toprule
Method & $\mathrm{mAP}_{.2}\uparrow$ & $\mathrm{WAP}_{.2}\uparrow$
& Mean$\uparrow$ & On$\uparrow$ & Off$\uparrow$ \\\\
\midrule
EgoSpeak MiniROADA A+V & 74.204 & 63.750 & 61.193 & 24.491 & 38.024 \\\\
Recent Qwen audio $\A$ & 79.692 & 84.100 & 60.508 & -- & -- \\\\
Omni global $\G$ & 73.446 & 77.867 & 60.849 & -- & -- \\\\
Omni $\G+\A$ & 81.723 & 85.066 & 65.109 & 25.960 & 45.251 \\\\
Omni $\G+\A+$pooled-$\V$ & \textbf{82.027} & \textbf{85.086}
& \textbf{65.400} & \textbf{26.019} & 45.371 \\\\
Current-frame person set F1 & $81.777{\pm}0.156$ & --
& $64.951{\pm}0.095$ & -- & -- \\\\
\bottomrule
\end{tabular}
\end{table*}
\subsection{Global Context and Recent Audio Are Complementary}
Table~\ref{tab:main} shows that $\A$ is strong at 0.2~s, while $\G$ is
@@ -238,6 +365,70 @@ the local-only head, so this comparison demonstrates predictive
complementarity, not that semantic reasoning alone causes the gain. A wider
history-matched control is required for a representation-level causal claim.
% Retained as a planning aid; illustrative, unmeasured patterns do not belong
% in the page-limited submission preview.
\iffalse
\begin{table*}[t]
\caption{Six-group \textbf{illustrative scenario, not measured results}.
These are conditional, pre-run interpretations for the pending matrix, not
EasyCom scores. $\Delta$ denotes paired mean-mAP change on common valid
cutoffs; signs and shape must be replaced by measured values even if contrary
to the story. L/T/C/B require seeds 0--2 and per-session reporting.}
\label{tab:scenario}
\centering
\normalsize
\renewcommand{\arraystretch}{1.12}
\setlength{\tabcolsep}{4.2pt}
\begin{tabular}{@{}p{0.095\textwidth}p{0.29\textwidth}p{0.29\textwidth}p{0.235\textwidth}@{}}
\toprule
Group & Frozen comparison & Illustrative pattern \emph{if observed} & Falsifier / interpretation limit \\
\midrule
L1--4 & $\A,\G,\G+\A,\G+\A+\V$; matched-width $\G$;
past-delayed local cues; current-state persistence
& $\Delta(\G+\A-\G)>0$ after width matching; delayed $\A$ loses
near-horizon benefit; persistence does not recover the gain
& Width-only or persistence matches fusion, or delay does not hurt:
do not attribute gain to timely distinct evidence. \\
\addlinespace[2.5pt]
T1--2 & 2-s completed-only vs 200-ms observed-tail refresh,
crossed with $\A$ on/off; causal replay and phase audit
& Tail helps most without $\A$; local $\A$ still adds at each refresh;
future-only media never changes prior readouts
& No independent local gain under tail refresh implies redundancy;
replay/leakage failure invalidates timing claims. \\
\addlinespace[2.5pt]
C1--2 & Genuine 2/4/6/8/10/12-s feature extraction; fixed 1-s $\A$;
add $\G$-only at each cap for a window-stability claim
& Fused performance plateaus around mid-range caps while
$\G$-only remains more cap-sensitive
& If long history substitutes for $\A$, local-evidence claim narrows;
without C2, no robustness comparison is justified. \\
\addlinespace[2.5pt]
B0--2 & Paired $\G$ and $\G+\A$ on Qwen 3B/7B and, after causal
interface audit, MiniCPM-o 4.5
& Positive within-backbone paired $\Delta$ on all admissible rows;
absolute backbone ranking is not inferred
& Failed causal/history match is unsupported, not zero gain;
one negative paired row defeats universal transfer. \\
\addlinespace[2.5pt]
H1/Q1 & Predefined onset/offset and other-pause/overlap slices;
same-horizon, cutoff-marked case selection
& Offset gains coexist with hard wearer-onset negatives; examples
explain, rather than replace, counted slice statistics
& Pure-negative slice AP is undefined; selected examples cannot
establish reduced false-entry rate. \\
\addlinespace[2.5pt]
S1 & End-to-end p50/p95 latency and peak memory, including I/O,
encoding, tail recomputation, local path, and boundaries
& A feasible throughput--quality tradeoff can be plotted
against 200-ms output cadence
& If p95 exceeds cadence, describe logical 5-Hz prediction only,
not real-time deployment. \\
\bottomrule
\end{tabular}
\end{table*}
\fi
\subsection{Generic Vision Does Not Recover the Available Signal}
Adding pooled $\V$ to $\G+\A$ produces only +0.304 points at 0.2~s and
@@ -245,32 +436,15 @@ Adding pooled $\V$ to $\G+\A$ produces only +0.304 points at 0.2~s and
averaged over horizons; onset/offset changes are +0.059/+0.120. A richer
current-frame person-set model is stable across seeds but reaches lower mean
mAP than the historical pooled row under a non-matched selection protocol.
These results do not support a claim of learned speaker grounding.
These results do not support a claim of learned speaker grounding. A separate
seed-0 no-box full-frame F3 screen reaches 82.38\% at 0.2~s and 65.54\%
mean mAP, versus 81.72/65.11\% for the existing $\G+\A$ row under the same
causal-valid dense protocol. F3 adds a two-frame 2-FPS token history and a
shared GRU, while head capacity and training batch differ; raw boundary
metrics and repeat seeds are unavailable. Thus the +0.66/+0.43-point
difference does not isolate visual motion or floor behavior.
\begin{table}[t]
\caption{Three-seed privileged-information audit (mean $\pm$ sample standard
deviation, \%). Every row includes $\G+\A$; activity conditions use only
past labels. Bold marks the best diagnostic, not a deployable model.}
\label{tab:oracle}
\centering
\scriptsize
\setlength{\tabcolsep}{3.2pt}
\begin{tabular}{@{}lccc@{}}
\toprule
Extra condition & $\mathrm{mAP}_{.2}$ & $\mathrm{WAP}_{.2}$ & Mean \\\\
\midrule
None (audio baseline) & $81.869{\pm}.049$ & $85.264{\pm}.110$ & $65.177{\pm}.058$ \\\\
Visibility only & $81.945{\pm}.098$ & $85.200{\pm}.144$ & $65.217{\pm}.048$ \\\\
Activity delayed 1 s & $81.951{\pm}.086$ & $85.270{\pm}.137$ & $65.341{\pm}.051$ \\\\
Shuffled person IDs & $85.917{\pm}.085$ & $85.577{\pm}.246$ & $66.460{\pm}.090$ \\\\
Per-person activity & $86.266{\pm}.182$ & $85.608{\pm}.220$ & $66.660{\pm}.135$ \\\\
Aggregate visible activity & $\mathbf{86.696{\pm}.085}$ & $\mathbf{85.836{\pm}.147}$
& $\mathbf{66.951{\pm}.022}$ \\\\
\bottomrule
\end{tabular}
\end{table}
Table~\ref{tab:oracle} locates the missing information. Aggregate visible
Table~\ref{tab:main}, panel B, locates the missing information. Aggregate visible
activity improves over the audio baseline by 4.826 points at 0.2~s and 1.775
mean-mAP points. Visibility alone changes mean mAP by only +0.040, and
one-second-delayed activity by +0.164. Thus availability or extra parameters
@@ -282,45 +456,73 @@ The majority of the oracle's 0.2-s macro gain comes from background and
others; wearer AP rises by only 0.572. This is why neither the oracle nor a
dense mAP gain establishes fewer false wearer entries.
\subsection{What the Audit Establishes}
\begin{figure}[t]
\centering
\fbox{\begin{minipage}[c][18mm][c]{0.94\columnwidth}
\centering
\textbf{Q1 case slots: examples pending}\\[2pt]
Onset / other-pause hard negative \quad|\quad Offset / overlap\\
Show source cutoff, observed activity and same-horizon wearer scores.
\end{minipage}}
\caption{Reserved H/Q case figure. Select examples by a frozen rule after
the slice counts in Table~\ref{tab:hard_slices} are available. No case or
behavioral improvement is asserted by this placeholder.}
\label{fig:hq_cases}
\end{figure}
Three conclusions survive the controls. First, a general-purpose global
state and a one-second acoustic readout provide different useful timescales.
Second, generic visual pooling has not converted visible people into reliable
local floor evidence. Third, perfect timely aggregate activity contains
recoverable information, whereas identity contributes little under the
current target. A dedicated causal active-speaker front end---designed for
mouth motion, blur, and short audio--visual synchrony as in egocentric ASD
\cite{huh2025egoasd}---is consequently a better-motivated next step than a
larger identity-aware fusion module.
\subsection{Pending Controls and Limits}
The evidence remains bounded. EasyCom has only three official test sessions;
the deployable matrix is single seed and has been examined repeatedly. The
oracle uses labels and is not a performance upper bound. Provided boxes omit
online detection cost, and logical 5-Hz output is not a measured throughput
claim. Finally, aggregate others cannot supply addressee or semantic
interruption ground truth. Confirmatory behavioral claims require a frozen
training-side operating point, competing-risk event attribution, and
multi-seed matched controls.
Tables~\ref{tab:stream_context}--\ref{tab:efficiency} reserve result slots
for T/C, B, H, and S; Fig.~\ref{fig:hq_cases} reserves Q cases. Panel B of
Table~\ref{tab:stream_context} separately reports a global-only chunk screen:
the 200-ms commits beat 2-s hold after startup exclusion but require about
ten times as many processor calls across 12 sessions. Freshness and chunk
construction both change, and the older tail bank is not extraction-matched;
these values do not fill the pending T/C factorial or establish real-time
throughput. L requires a
trained width-matched global control and past-delayed features on identical
valid pairs; T crosses tail refresh with local audio; C re-extracts each
causal context cap and pairs it with a global-only run. B compares the
within-backbone audio increment only after readout and history audits.
H/Q reports slice counts and cutoff-marked examples; S measures full-path
latency and memory. The oracle uses privileged labels, provided boxes omit
online detection, and aggregate others cannot establish addressee or
semantic floor ownership.
\subsection{Decision Rules and Reproducibility}
The unit of comparison is the same physical cutoff and future target time,
not an arbitrary feature row. For every new condition we will archive
input-source timestamps, common valid-pair counts, seeds, per-session AP,
trainable parameter counts, processor/model revisions, checkpoint hashes,
and prediction scores. Frames and horizons are correlated, not independent
replicates.
We retain the fixed four-epoch recipe for the matched matrix. Any loss
weight, threshold, context selection, or case-selection rule is frozen
using training-side evidence before looking at Sessions~1--3. Because
these test sessions have already informed this research program, even
new seed runs remain exploratory rather than restoring an unseen test set.
The raw endpoint AP in Table~\ref{tab:main} may motivate a behavioral
hypothesis, but an ENTRY/YIELD error-rate claim additionally requires
one-event-one-vote attribution with response windows censored at the next
other onset and yield windows at the next other offset. Until that
competing-risk evaluator passes real-timeline audit, we report only dense
forecasting and endpoint anticipation.
\section{Conclusion}
We presented a strictly causal global--local audit of egocentric wearer speech
anticipation. Frozen Omni context and recent audio are strongly complementary,
especially for future wearer cessation. In contrast, pooled or current-frame
person features do not recover the local-floor signal revealed by a causal
visible-activity oracle. The actionable conclusion is deliberately narrow:
the next bottleneck is timely, learnable local activity evidence, not simply
more multimodal capacity or persistent identity. This distinction provides a
clearer target for future egocentric conversational agents and prevents dense
forecasting gains from being mistaken for semantic floor control.
In this strictly causal audit, frozen Omni context and recent audio improve
wearer activity forecasting, especially future speech cessation. Generic
pooled vision does not recover the timely visible-activity signal exposed by
the analysis-only oracle. Matched controls and censored event evaluation
remain necessary before claiming improved floor behavior.
\section{Acknowledgment}
OpenAI Codex assisted with substantive drafting and figure layout in the
abstract, introduction, and presentation of the archived analysis; the
authors remain responsible for verification, experimental claims, and the
final manuscript.
OpenAI Codex assisted with drafting and figure layout; the authors remain
responsible for all experimental claims and final content.
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