A Lightweight Library for Augmented Reality Applications

摘要

To build an Augmented Reality (AR) application it is necessary to recognize a fiducial marker, then to calibrate the camera that is viewing the 3D scene on the marker, and finally to draw a virtual object over the image taken by the camera but in the virtual coordinate system supposed also on the fiducial marker. The camera calibration step give us the transformation matrix from 3D world to 2D on the screen, and the pose of the marker with respect to the virtual coordinate system. An AR application must run interactively with the user, and also in real time. Performing all these calculations in a embedded device such as a Single Board Computer (SBC), a tablet, or a smartphone, is a challenge because a normal numerical analysis library is huge, and it is not designed for such devices. In this article we present a lightweight numerical library, it has been developed thinking in such computing restricted devices. We show results on two AR applications developed for the Raspberry Pi 3 SBC.