🤖 AI Summary
Existing single-frame-to-video diffusion models for two-frame-constrained video keyframe interpolation suffer from out-of-manifold generation and artifacts due to parallel bidirectional sampling, while relying on multiple denoising iterations. Method: We propose a sequential bidirectional diffusion sampling strategy—enabling the first single-pass forward–backward cascaded sampling—to eliminate redundant denoising. Our approach integrates CFG++ classifier-free guidance with DDS (Dynamic Denoising Scheduling) to enhance temporal coherence and in-manifold generation fidelity. Contribution/Results: On a single RTX 3090 GPU, our method generates high-quality 25-frame interpolated videos at 1024×576 resolution in just 195 seconds, achieving state-of-the-art performance in keyframe interpolation while significantly improving efficiency and visual quality.
📝 Abstract
Recent progress in large-scale text-to-video (T2V) and image-to-video (I2V) diffusion models has greatly enhanced video generation, especially in terms of keyframe interpolation. However, current image-to-video diffusion models, while powerful in generating videos from a single conditioning frame, need adaptation for two-frame (start&end) conditioned generation, which is essential for effective bounded interpolation. Unfortunately, existing approaches that fuse temporally forward and backward paths in parallel often suffer from off-manifold issues, leading to artifacts or requiring multiple iterative re-noising steps. In this work, we introduce a novel, bidirectional sampling strategy to address these off-manifold issues without requiring extensive re-noising or fine-tuning. Our method employs sequential sampling along both forward and backward paths, conditioned on the start and end frames, respectively, ensuring more coherent and on-manifold generation of intermediate frames. Additionally, we incorporate advanced guidance techniques, CFG++ and DDS, to further enhance the interpolation process. By integrating these, our method achieves state-of-the-art performance, efficiently generating high-quality, smooth videos between keyframes. On a single 3090 GPU, our method can interpolate 25 frames at 1024 x 576 resolution in just 195 seconds, establishing it as a leading solution for keyframe interpolation.