Demo: Spatial augmented reality for physical drawing

International audienceSpatial augmented reality (SAR) makes possible the projection of virtual environments into the real world. In this demo, we propose to demonstrate our SAR tools dedicated to the creation of physical drawings. From the most simple tools: the projection on virtual guidelines enabling to trace lines and curves to more advanced techniques enabling stereoscopic drawing through the projection of a 3D scene. This demo presents how we can use computer graphics tools to ease the drawing, and how it will enable new kinds of physical drawings

Digitally assisted stereo drawing

International audienceWith the increasing range of available stereoscopic rendering devices, stereoscopic images and videos are reaching the general public. Creating such pairs of images digitally from 3D content is easy to tweak and adjust. On the other hand, drawing directly stereoscopic scenes on a sheet of paper is very hard to perform. In this paper, we focus on such an interactive task where interactive 3D graphics and novel user interfaces are combined together to create stereoscopic drawings from a standard pen and paper interface. Our system is based on augmented reality, multitouch, and 3D spatial interaction, to enhance interaction with the 3D scene. The projection of the left and right views on the paper guides the users in their stereoscopic drawing task, while maintaining a high level of expressiveness. This work is a first step towards promising full applications for interactive drawing of 3D stereoscopic images

SPATIO-TEMPORAL REGISTRATION IN AUGMENTED REALITY

The overarching goal of Augmented Reality (AR) is to provide users with the illusion that virtual and real objects coexist indistinguishably in the same space. An effective persistent illusion requires accurate registration between the real and the virtual objects, registration that is spatially and temporally coherent. However, visible misregistration can be caused by many inherent error sources, such as errors in calibration, tracking, and modeling, and system delay. This dissertation focuses on new methods that could be considered part of "the last mile" of spatio-temporal registration in AR: closed-loop spatial registration and low-latency temporal registration: 1. For spatial registration, the primary insight is that calibration, tracking and modeling are means to an end---the ultimate goal is registration. In this spirit I present a novel pixel-wise closed-loop registration approach that can automatically minimize registration errors using a reference model comprised of the real scene model and the desired virtual augmentations. Registration errors are minimized in both global world space via camera pose refinement, and local screen space via pixel-wise adjustments. This approach is presented in the context of Video See-Through AR (VST-AR) and projector-based Spatial AR (SAR), where registration results are measurable using a commodity color camera. 2. For temporal registration, the primary insight is that the real-virtual relationships are evolving throughout the tracking, rendering, scanout, and display steps, and registration can be improved by leveraging fine-grained processing and display mechanisms. In this spirit I introduce a general end-to-end system pipeline with low latency, and propose an algorithm for minimizing latency in displays (DLP DMD projectors in particular). This approach is presented in the context of Optical See-Through AR (OST-AR), where system delay is the most detrimental source of error. I also discuss future steps that may further improve spatio-temporal registration. Particularly, I discuss possibilities for using custom virtual or physical-virtual fiducials for closed-loop registration in SAR. The custom fiducials can be designed to elicit desirable optical signals that directly indicate any error in the relative pose between the physical and projected virtual objects.Doctor of Philosoph