4DGen: Grounded 4D Content Generation with Spatial-temporal Consistency
(2312.17225)Abstract
Aided by text-to-image and text-to-video diffusion models, existing 4D content creation pipelines utilize score distillation sampling to optimize the entire dynamic 3D scene. However, as these pipelines generate 4D content from text or image inputs, they incur significant time and effort in prompt engineering through trial and error. This work introduces 4DGen, a novel, holistic framework for grounded 4D content creation that decomposes the 4D generation task into multiple stages. We identify static 3D assets and monocular video sequences as key components in constructing the 4D content. Our pipeline facilitates conditional 4D generation, enabling users to specify geometry (3D assets) and motion (monocular videos), thus offering superior control over content creation. Furthermore, we construct our 4D representation using dynamic 3D Gaussians, which permits efficient, high-resolution supervision through rendering during training, thereby facilitating high-quality 4D generation. Additionally, we employ spatial-temporal pseudo labels on anchor frames, along with seamless consistency priors implemented through 3D-aware score distillation sampling and smoothness regularizations. Compared to existing baselines, our approach yields competitive results in faithfully reconstructing input signals and realistically inferring renderings from novel viewpoints and timesteps. Most importantly, our method supports grounded generation, offering users enhanced control, a feature difficult to achieve with previous methods. Project page: https://vita-group.github.io/4DGen/
Overview
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The paper presents a novel approach to 4D content generation that is more efficient and less computationally demanding.
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A multi-stage generation pipeline is introduced which uses static 3D assets and monocular video sequences to create dynamic 4D scenes.
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Dynamic 3D Gaussians are used for 4D representations to ensure high-resolution training and renderings.
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Spatial-temporal pseudo labels and consistency priors are incorporated to maintain visual consistency across both space and time.
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The approach significantly outperforms older methods, providing better details and smoother transitions in generated content.
Introduction to 4D Content Generation
The creation of dynamic 3D content, often referred to as 4D, has become a pivotal area of research due to the increasing demand for content with both spatial and temporal dimensions. Traditional methods generally rely on intensive prompt engineering and high computational costs, which can lead to significant obstacles in practical applications. Acknowledging the limitations of existing systems, this paper introduces a new approach to 4D content generation that aims to streamline and enhance the overall process.
A Novel Multi-Stage 4D Generation Pipeline
At the heart of this method lies a multi-stage generation pipeline that simplifies the complexity of creating 4D content. By decomposing the process into distinct stages, the method targets static 3D assets and monocular video sequences as the core components for constructing the 4D scene. This design offers users the unprecedented ability to direct the geometry and motion of the content, allowing for the specification of both appearance and dynamics through a static 3D asset or video input.
The innovation extends further with the adoption of dynamic 3D Gaussians for 4D representation, which contributes to high-quality, high-resolution supervision during training. Spatial-temporal pseudo labels and consistency priors are also integrated into this framework, enhancing the plausibility of renderings from any viewpoint at any point in time.
Embracing Spatial-Temporal Consistency
Recognizing the challenge of generating content that is not only visually appealing but also consistent across time and space, the authors have employed a combination of techniques to address this issue. Pseudo labels on anchor frames—drawn from a pre-trained diffusion model—are utilized to educate the representation on spatial-temporal dimensions, while seamless consistency priors adopted from score distillation sampling and unsupervised smoothness regularization reinforce the temporal coherence of intermediate frame renderings.
Advancements and Experimental Results
The freshly proposed framework evidently outperforms existing methods in both spatial and temporal metrics, yielding more detailed renderings with smoother transitions across frames. Experimentation across various datasets validates the superiority of this approach in faithfully reconstructing input signals and delivering plausible synthesis for unseen viewpoints and timeframes.
In summary, the newly presented 4DGen system profoundly enhances user control and simplifies the content generation process, marking a significant stride forward in the field of dynamic 3D asset generation.