## Why OraRL
- **Annotation-as-rollout:** annotations become reliable positive rollouts while
policy samples retain an on-policy baseline.
- **Seven task families:** one update rule covers temporal and spatial grounding,
segmentation, tracking, spatial-temporal grounding, video QA, and spatial
intelligence.
- **Efficient training (4B):** sign-balanced pruning delivers **1.48× faster
updates** (**92.5 → 62.4 s/step**) while reducing peak per-GPU memory from
**62.4 to 50.9 GB**.
- **Efficient inference:** on one H20 with vLLM in BF16, weight loading occupies
**8.6 GiB (4B)** and **17.6 GiB (9B)**. On ten-minute, 2-fps videos,
answer-only decoding cuts median post-TTFT latency from **4.78 s to 130 ms**
and total latency from **29.03 to 24.30 s**.
- **Multimodal veRL infrastructure:** a unified video contract carries cached
artifacts, raw paths, or inline frame tensors through vLLM rollouts and FSDP
updates, with decode-once frame reuse, temporal metadata, task-grouped
batching, asynchronous Ray rewards, and safe hybrid-engine cache handling.
## OraRL in One Update