Single-image 3D reconstruction dropped diffusion sampling and cut inference to 36 seconds per scene
AspireAI community · arXiv
Most recent single-image 3D reconstruction methods lean on camera-controlled video diffusion models, which means iterative diffusion sampling at inference and limited practical use. PRISM observes that geometric forward warping alone can already cover most of a target view from the input image, leaving a compact residual for an encoder to correct, so it splits multi-view latent prediction into a parameter-free geometric prior plus a learned residual correction with no diffusion sampling at inference. A two-stage training strategy combines latents supervised distillation for geometric generalisation with perceptual fine-tuning for appearance quality, which is what lets it generalise from purely synthetic training data. Across three benchmarks PRISM reached competitive reconstruction quality against diffusion-based methods while cutting inference to 36 seconds per scene. The trade-off is that it is a feed-forward approach: it trades the generative flexibility and diversity of a diffusion prior for deterministic speed, and quality is reported as competitive rather than better.
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