Molmo2 Codec

V6 evidence snapshot: Stage-1 matched-P reconstruction controls, untuned RGB/Hphi/P boundary probe, mixed-8K Stage-2 regression, and 20-step counterfactual repair with strict P-content gates.

Untuned-LLM MLVU n=200 control: RGB81 61.5%, Hphi81 61.5%, real P16 58.5%, with exact evaluation contract and separation from the earlier native probe.

Unified V6 audit: Molmo-native 144-to-16 P-tokenizer, initialization/freezing evidence, real-video motion oracle results, and explicit Stage-1/Stage-2 readiness gates

Visual audit of 16 direct queries vs 64-to-16 latent topology, block attention mask, Molmo native connector, and the Stage-1/Stage-2 hand-off

Visual audit of the own-search codec front end: ViT-aligned 14x14 blocks, 2-fps +/-48 hierarchical search, adaptive pcost GOP, verified lambda scaling, motion saturation, gamma calibration, and Kmax issues

P0 diagnosis: P-token native-interface mismatch, missing block mask, broken Stage-1/2 bridge; V5 temporal fix is useful but insufficient; V6 pilot recommended before scaling

Root cause = P-tokenizer capacity (0.49M frozen vs 576M); V4 trainable E_P fixes the proxy

Deep architecture comparison: learned delta P-tokens vs codec-guided sparse RGB canvases, with a hybrid recommendation for Molmo2.