Diffusion Time-step Curriculum for One Image to 3D Generation
Authors: Xuanyu Yi, Zike Wu, Qingshan Xu, Pan Zhou, Joo-Hwee Lim, Hanwang Zhang

Score distillation sampling (SDS) has been widely adopted to overcome the absence of unseen views in reconstructing 3D objects from a single image. It leverages pre-trained 2D diffusion models as teacher to guide the reconstruction of student 3D models. Despite their remarkable success SDS-based methods often encounter geometric artifacts and texture saturation. We find out the crux is the overlooked indiscriminate treatment of diffusion time-steps during optimization: it unreasonably treats the student-teacher knowledge distillation to be equal at all time-steps and thus entangles coarse-grained and fine-grained modeling. Therefore we propose the Diffusion Time-step Curriculum one-image-to-3D pipeline (DTC123) which involves both the teacher and student models collaborating with the time-step curriculum in a coarse-to-fine manner. Extensive experiments on NeRF4 RealFusion15 GSO and Level50 benchmark demonstrate that DTC123 can produce multi-view consistent high-quality and diverse 3D assets. Codes and more generation demos will be released in https://github.com/yxymessi/DTC123.