In this issue, we have four regular papers followed by four selected papers from 3DOR 2014. The first regular paper is Procedure-based component and architecture modeling from a single image by Fei Hou, Hong Qin and Yue Qi. The second paper is entitled Separable soft shadow mapping by Jose María Buades Jesús Gumbau and Miguel Chover. The third paper is Large-scale three-dimensional measurement based on LED marker tracking by Jinlong Shi and Zhengxing Sun. Finally the last regular paper is Animating with style: defining expressive semantics of motion by Klaus Förger and Tapio Takala. The remaining papers are described in the preface of the 3DOR section.

Nadia Magnenat-Thalmann

Editor-in-Chief

Preface to the 3DOR14 papers’ section

The 3DOR workshop series provides a unique venue for researchers, students, and practitioners interested in the definition, evaluation, and application of 3D object analysis and retrieval. This is an active research area that unifies different fields like Computer Vision, Computer Graphics, Machine Learning, Cognitive Science, Human-Computer Interaction, and Multimedia Information Retrieval. Its main goal is to advance the state of the art of techniques for 3D data acquisition, segmentation, feature extraction, classification, and 3D object matching. This special issue presents four extended versions of selected papers presented at the 3DOR 2014 Workshop, which was held on April 6th in Strasbourg, France.

These extended papers underwent a full round of additional reviewing, done by some of the reviewers of the original workshop papers and by ourselves.

In the article “Robust Motion Flow for Mesh Tracking of Freely Moving Actors”, Blache et al. expose a method for tracking actor in 4D data. In the article “Retrieval and classification methods for textured 3D models: A comparative study”, Biasotti et al. present a taxonomy and an extensive comparative study of techniques that take advantage of texture information in 3D models for retrieval tasks. In the article “Spatio-temporal Segmentation for the Similarity Measurement of Deforming Meshes”, Luo et al. propose both a novel segmentation technique for deforming meshes and a similarity measure based on the output of the segmentation. Finally, in the article “A Robust Spatio-Temporal Scheme for Dynamic 3D Facial Expression Retrieval”, Danelakis et al. describe a new spatio-temporal descriptor aimed specifically for 3D facial expression retrieval.

We would like to thank all international reviewers for their excellent work in refereeing the papers for this special issue. Also, we would like to thank all authors of this collection of papers, which made a great effort to improve their original articles and to address all the comments from the reviewers. Last but not least, we would like to thank the Editors of The Visual Computer for making possible this special issue. We hope that you enjoy reading these articles from this fascinating research area.

Benjamin Bustos

Hedi Tabia

Jean-Philippe Vandeborre

Remco Veltkamp

Xiaoyang Mao

Lichan Hong