Research 1

 

3D e-Heritage / Cyber Archaeology

Sensor

Shape analysis

  • Analysis of historical sculptures

    3D shape comparison with digital copies draws increasing attention in modern culture heritage studies. Our aim is to analyze portrait sculptures of Augustus with 3D scanned data. A feasible framework of automatic object categorization is proposed based on shape comparison, where distinguishing regions are simultaneously detected as well. High coincidence between our result and previous archaeological speculations is observed in validation experiments, which confirms the validity of the proposed method.

    • M. Lu, Y. Zhang, B. Zheng, T. Masuda, S. Ono, T. Oishi, K. Sengoku-Haga, and K. Ikeuchi, "Portrait Sculptures of Augustus: Categorization via Local Shape Comparison," International Congress on Digital Heritage, Vol. 1, pp. 661-664, Marseille, France, Oct. 28-Nov. 1 2013.
    • Y. Zhang, M. Lu, B. Zheng, T. Masuda, S. Ono, T. Oishi, K. Sengoku-Haga and K. Ikeuchi, "Classical Sculpture Analysis via Shape Comparison," International Symposium on Culture and Computing 2013, Kyoto, Japan.
  • Face classification

    The Bayon temple in Cambodia was built in the 12th century and is famous for its towers with four faces at the four cardinal points. According to research by JSA (Japanese government team for Safeguarding Angkor), the faces can be classified into three groups based on subjective criteria. We explore a more objective way to classify the faces by using measured 3D geometrical models. After alignment of 3D faces in the same coordinate system, orientation, and normalization, we captured in-depth images of each face and then classified them by several statistical methods.

Visualization

  • Cloud rendering

    We developed an interactive rendering system for large scale 3D mesh models, stored on a remote machine through relatively small capacity of networks. Our system uses both model and image based rendering methods for efficient load balance between a server and clients. On the server, the 3D models are rendered by the model-based method using a hierarchical data structure with multi-resolution. On the client, it reconstructs an arbitrary view by using a novel image-based method, referred to as the Grid-Lumigraph, with blending image colors from sampling images received from the server. The resulting rendering system can efficiently render any image in real-time.

3D reconstruction

  • Alignment / Merging / Texturing

    These are huge objects existing outdoors and providing various technical challenges. Geometric models of the cultural heritage assets are digitally achieved through a pipeline, consisting of acquiring data, aligning multiple range images, and merging these images. We have developed alignment algorithms: a rapid simultaneous algorithm for quick data checking on site, and a parallel alignment algorithm for precise adjustment. We have also designed a parallel voxel-based merging algorithm for connecting all aligned range images. The texture images acquired by color cameras are aligned onto the geometric models. In an attempt to restore the original appearance of historical objects, we have synthesized several buildings and statues using scanned data and a literature survey.

  • IP registration / application to ultrasound images

    We proposed a novel registration method based on a coarse-to-fine IP representation. The approach starts from a high-speed and reliable registration with a coarse (of low degree) IP model and stops when the desired accuracy is achieved by a fine (of high degree) IP model. Over the previous IP-point based methods our contributions are: (i) keeping the efficiency without requiring pair-wised correspondences, (ii) enhancing the robustness, and (iii) improving the accuracy.