cs.CVOct 20, 2026

Pair-Free Coarse-to-Real Video Generation via Real-to-Coarse Image Supervision

Authors: Gonzalo Gómez-Nogales, Daohan Lu, Peiye Zhuang, Tinghui Zhou, Yi Zhou

Organizations: Universidad Rey Juan Carlos · New York University · Roblox · Adobe

Abstract

Coarse-to-real (C2R) video generation converts coarse animation, simulation, or game-rendered videos into photorealistic videos while preserving scene layout, camera motion, and dynamics. Training such models requires aligned (coarse, realistic) video pairs, which are expensive to create and confine prior systems to narrow synthetic domains. We exploit a simple asymmetry: paired videos are hard to obtain, but paired real-to-coarse images are easy to construct with existing editing and 3D reconstruction tools. Using these image pairs, we train the DINO-R2C model to transfer realistic images to coarse images in DINO feature space, and apply it frame-wise to ordinary real videos to synthesize pseudo-coarse videos. The C2R# model then learns to generate each real video from its pseudo-coarse counterpart, free from needing (coarse, realistic) video pairs. At inference, the DINO-R2C model is discarded and actual coarse videos drive the C2R# model directly. Thus, our pair-free training scales with any real-video corpora rather than with paired synthetic videos. We will release the model and project webpage at https://gonzalognogales.github.io/coarse2real-sharp/.

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