Flexible projector calibration for active stereoscopic systems

Abstract

This contribution deals with the calibration of active stereoscopic systems consisting of a camera and a structured light projector. Usually, expensive equipments like precise calibration pieces or dedicated positioning devices are used for the projector calibration. We developed a flexible calibration method using only a planar target as calibration board without other equipment. The method requires only two image acquisitions from which the projector parameters are estimated using an optimization method. A quantitative evaluation demonstrates the accuracy and flexibility of the proposed calibration method.

From 2D towards 3D cartography of hollow organs

“…From (12) and (13) we finally deduce (14). For at least four P i,k+1 3D points (in practice i ∈ (i, .…”

“…6, and [14]). Due to the weak number of dots and their small size, each green dot projection is only spread over a few image pixels.…”

“…The 3D point coordinate transformation is guided by the successive registrations of consecutive I k and I k+1 image pairs. Similar to the 2D mosaicing method, and prior to the registration, the images are being converted in grey levels and their distortions are corrected [14] (in the following, I k stands for these distortion free grey level images). However, the final 3D map which will be superimposed on the reconstructed surface will include the color information.…”

Flexible calibration of structured-light systems projecting point patterns

“…Our method requires a planar calibration board only, which is a paper sheet with circular control disks attached to a planar PolyMethyl MethAcrylate (PMMA) surface. A preliminary version of this active vision system calibration method was sketched in the conference paper [21]. In this paper, we show how the calibration can be extended to other systems projecting different patterns, i.e., with a variable number of points and various spatial distributions of the points depending on the application.…”

Digital Sand Model using Virtual Reality Workbench

“…Typical modern workbenches consist of a display area on the surface of an elevated platform such as a table-top that displays a stereo image and the multiple users view the stereo image using the 3D glasses. In this project, Active stereoscopy [18] is used wherein the users wear Liquid Crystal shutter glasses for viewing the stereo image and the table structure is constructed using slotted angles, mirror and tracing sheet.…”