Pushing the Limits of 3D Color Printing: Error Diffusion with Translucent Materials

Accurate color reproduction is important in many applications of 3D printing, from design prototypes to 3D color copies or portraits. Although full color is available via other technologies, multi-jet printers have greater potential for graphical 3D printing, in terms of reproducing complex appearance properties. However, to date these printers cannot produce full color, and doing so poses substantial technical challenges, from the shear amount of data to the translucency of the available color materials. In this paper, we propose an error diffusion halftoning approach to achieve full color with multi-jet printers, which operates on multiple isosurfaces or layers within the object. We propose a novel traversal algorithm for voxel surfaces, which allows the transfer of existing error diffusion algorithms from 2D printing. The resulting prints faithfully reproduce colors, color gradients and fine-scale details.Comment: 15 pages, 14 figures; includes supplemental figure

Mobile graphics: SIGGRAPH Asia 2017 course

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Interactive 3D Visualization of a Large University Campus over the Web

Nowadays, with the rise and generalized use of web applications and graphical hardware evolution, one of the most interesting problems deals with realistic real-time visualization of virtual environments on web browsers. This paper shows an on-line application to dynamically visualize a large campus on the World Wide Web. The application focuses on a smooth walk through a large 3D environment in real-time as an alternative way to index geographically related information. This way, contents are continuously filtered based on viewpoint¿s position. This can be made thanks to the availability of different models corresponding to different levels of detail (LOD) for each modeled building. A server storage model has been purposed including all models, compound of meshes, textures and information. The technique is based on an algorithm that performs a progressive refining of the models, according to the distance from the viewpoint.Vendrell Vidal, E.; Sanchez Belenguer, C. (2011). Interactive 3D Visualization of a Large University Campus over the Web. International Journal of Computer Information Systems and Industrial Management Applications. 3:514-521. http://hdl.handle.net/10251/35020S514521

Device-based decision-making for adaptation of three-dimensional content

The goal of this research was the creation of an adaptation mechanism for the delivery of three-dimensional content. The adaptation of content, for various network and terminal capabilities - as well as for different user preferences, is a key feature that needs to be investigated. Current state-of-the art research of the adaptation shows promising results for specific tasks and limited types of content, but is still not well-suited for massive heterogeneous environments. In this research, we present a method for transmitting adapted three-dimensional content to multiple target devices. This paper presents some theoretical and practical methods for adapting three-dimensional content, which includes shapes and animation. We also discuss practical details of the integration of our methods into MPEG-21 and MPEG-4 architecture

Acceleration of stereo-matching on multi-core CPU and GPU

This paper presents an accelerated version of a dense stereo-correspondence algorithm for two different parallelism enabled architectures, multi-core CPU and GPU. The algorithm is part of the vision system developed for a binocular robot-head in the context of the CloPeMa 1 research project. This research project focuses on the conception of a new clothes folding robot with real-time and high resolution requirements for the vision system. The performance analysis shows that the parallelised stereo-matching algorithm has been significantly accelerated, maintaining 12x and 176x speed-up respectively for multi-core CPU and GPU, compared with non-SIMD singlethread CPU. To analyse the origin of the speed-up and gain deeper understanding about the choice of the optimal hardware, the algorithm was broken into key sub-tasks and the performance was tested for four different hardware architectures