Building blocks¶
Tags: [STD] re-implement · [EXT] extend to our setting · [NEW] genuine contribution (see
index).
SSL backbone [STD]: default MAE for the pipeline (stable; reconstruction error is a free per-frame
informativeness signal). MAE is collapse-resistant (a constant code can't reconstruct diverse pixels), so the
collapse demonstration uses a joint-embedding method (SimSiam/BYOL/DINO/SimCLR) — MAE's own degradation mode is
forgetting/overspecialization. We start with SimSiam as the minimal joint-embedding variant (predictor +
stop-gradient, no EMA target, no negatives — fewest moving parts, and its stop-gradient is precisely the
collapse-avoidance mechanism under study), expanding to BYOL then SimCLR once the dynamics are established. Adapt an
ImageNet-pretrained backbone (data too small for from-scratch); ViTDet-compatible if detection is a target. Methods
used as-is: MAE (He 2022), SimSiam/BYOL/DINO/SimCLR (Chen & He 2021 / Grill 2020 / Caron 2021 / Chen 2020).
Filter families (the knobs):
- (F-a) Latent-feature tracking — novelty criterion
[EXT]. Encode → PCA to 8–32D metric space → score = kNN/Mahalanobis distance to a same-domain reference set (frozen reference encoder; not UMAP). Extends: embedding-space OOD scoring — kNN-OOD (Sun 2022), Mahalanobis (Lee 2018), Deep SVDD (Ruff 2018) — built to flag OOD at test time; we repurpose them as a streaming, label-free, single-pass training-selection signal. - (F-b) Streaming core-set — coverage criterion
[EXT]. Maintain a buffer that geometrically covers the seen embedding distribution. Extends: core-set / k-center (Sener & Savarese 2018), herding (Welling 2009 / iCaRL Rebuffi 2017), prototypicality (Sorscher 2022), GSS (Aljundi 2019) — offline or supervised-CL coverage methods; we run them as streaming, label-free buffer maintenance over the SSL embedding. - (F-c) Health-steerable filter
[NEW](N-G). Explicit mixα·coverage + (1−α)·novelty+ acceptance rate, both set live by the monitor. The actuator for the closed loop. Contrasts with: D2 Pruning (2024) / CCS (2023), which have the coverage/difficulty mix but fix it offline; here it is a controlled variable. A frozenαreduces F-c to a hybrid[EXT]baseline (= B-open). - Temporal-robustness layer
[EXT]. Denoise the per-frame signal, separating sustained shifts (true novelty) from impulsive spikes (sensor noise). Extends: view-disagreement OOD (RSS-MGM) and forgetting/difficulty (FALSE) from the label-noise line, plus drift/change-point detection (ADWIN, Page-Hinkley); we transpose to label-free streaming SSL and add a sustained-vs-impulsive persistence test.
Datasets (what we run on, and why):
- STL-10 — Phase 0 + Phase 1 pilot. SSL-purpose-built (100k-image unlabeled split, 96px), small enough for CPU smoke tests and fast iteration, clean 10-class labels for linear-probe / kNN eval. Correlation is synthetic (class-blocked ordering). Role: validate the loop + instruments + positive control cheaply — the harness, not the headline.
- TinyImageNet / ImageNet-100 — optional. A larger non-driving SSL scale check, if STL-10 proves too small to stress the backbone.
- BDD100K — Phase 1 make-or-break. Real driving video → genuine temporal correlation, the property that makes selection meaningful (a make-or-break on shuffled toy data won't convince reviewers). Built-in weather / scene / time-of-day attribute labels → ready-made label-efficiency probes and natural era boundaries. GPS/IMU → the optional telemetry fused-input ablation. Standard, respected benchmark.
- ZOD (Zenseact Open Dataset) — Phase 4 confirmation. In-house partner data; confirms the findings transfer to the consortium's own automotive distribution and the use case the project ultimately serves. Multimodal (camera/LiDAR + vehicle/GNSS signals).
- nuScenes — optional alternative. Use if the telemetry-fusion ablation needs tighter time-synchronized CAN-bus signals than BDD provides.
Ordering rationale: cheap harness (STL-10) → real-correlation make-or-break (BDD100K) → in-house confirmation (ZOD) —
matching the "instrument & demonstrate first" sequence. Dataset choice is not tagged [STD]/[EXT]/[NEW]: a dataset
isn't a contribution, so the tags (which mark method novelty) don't apply.