| name | simple-microchunk-rejection |
| description | Use when working on SIMPLE's streaming microchunk class-average rejection, simple_microchunked2D lifecycle sentinels, pass-1/pass-2/refchunk/match generation, skip_pass_2 behavior, simple_cluster2D_rejector criteria, or boundaries with model_cavgs_rejection. |
SIMPLE Microchunk Rejection
Use this skill for src/main/stream/simple_microchunked2D.f90, src/main/stream/simple_cluster2D_rejector.f90, and stream integration questions involving model_cavgs_rejection.
Read First
doc/microchunk_and_rejection/microchunk_rejection_policy.mddoc/microchunk_and_rejection/microchunk_rejection_model_integration.mddoc/microchunk_and_rejection/model_cavgs_rejection.md when comparing the rule engine with the learned model backend.
Live Ownership
simple_microchunked2D owns stream lifecycle, sentinel reconstruction, tier generation, match finalization, and combined outputs. simple_cluster2D_rejector owns the live scalar rejection rules. src/main/cavg_quality and model_cavgs_rejection are separate unless a task explicitly integrates them.
Sentinel Contract
Restart state is reconstructed from sentinel files:
ABINITIO2D_FINISHED: chunk job finished.REJECTION_FINISHED: rejection and particle cleanup finished.REJECTION_FAILED: rejection could not be performed safely.COMPLETE: chunk was consumed or finalized.
On import, failed chunks count as rejection-complete and complete. Do not consume a source chunk into the next tier until its project file for the next tier has been written successfully.
Rejection Rules
The live rejector applies cumulative class-average rejection in this order:
- population, with tier-specific fractions;
- resolution, rejecting
res > 40.0;
- foreground mask geometry after low-pass/Otsu/connected-component cleanup;
- local variance, including unconditional rejection of both-zero scores.
After rejection, rejected classes map to particle state=0, and rejected particles must have class=0 and class_match=0.
Tier Flow
The normal ladder is pass-1 -> pass-2 -> refchunk -> match. Pass-1 chunks become complete only after pass-2 projects are written. Pass-2 chunks feed the refchunk but are marked complete only after match chunks are generated. Match finalization updates accepted/rejected counters, writes COMPLETE, and copies project files to the completion directory.
When skip_pass_2 is active, pass-2 import and generation are skipped. Rejection-complete pass-1 chunks feed the refchunk directly, and remaining pass-1 chunks become match chunks directly after the reference stack and box are available.
Model Backend Boundary
model_cavgs_rejection is a learned feature-vector backend with hard validity gates, normalized features, model weights, clustering, and threshold controls. It currently exposes chunk_default_v2, chunk_lp4, pool_default_v2, microchunk_p1, and microchunk_p2 presets. Do not replace stream rejection decisions with model output unless the task also preserves stream sentinels, selected/rejected stacks, project state propagation, and match/finalization semantics.
