NVlabs (SoL-Engine research blog, SANA project page) · Open video refiner

Open-H3-Regenerate-2K

Open-H3-Regenerate-2K is an open replacement for the hosted H3-Regenerate-2K API, which refines low-resolution drafts from the H3 video model and has no released weights. It accepts a draft at any low resolution (for example 384P to 768P), made by H3 or another model such as LTX-2 or SANA-Video. It regenerates the draft natively at 768P, 1080P, 2K or 4K, for clips of 5 to 15 seconds in one pass. The H3 transformer and VAE stay frozen and only a refiner LoRA is trained, using real high-resolution clips paired with degraded copies. At inference a community latent upscaler enlarges the draft latent directly, then three Euler denoising steps redraw the detail, using a LoRA merged with community distillation adapters. For a 5-second 2K clip on one B200, the pipeline takes 22.45 s against 87.26 s for the official API. On RefinerBench-150 at 2560 × 1440 it scores higher than the official API on all three UniPercept axes and on VBench aesthetic quality, imaging quality and subject consistency, and was preferred in 87% of 200 blinded judgments. The page links code for SoL-Engine and SoL-Refiner but does not state a licence or release date in the page.