Multi-media Projector – Single Camera Photogrammetric System for Fast 3d Reconstruction

Some of the important technical characteristics of photogrammetric system are the speed of 3D acquisition, automation and possibility for smart operating. Using structured and coded light allows to solve correspondence problem fast, robustly and accurate. And applying of PC-controlled structured light provides a possibility to make a step to highly automated and intellectual photogrammetric systems. Multi-media projectors have a number of features which make them attractive for using in photogrammetric application. The main of these features are high technical characteristics (such as brightness, contrast, signal/noise ratio, resolution) and a reasonable price. And the main advantage of digital projector is a capability of smart lighting for applying smart processing algorithms. A traditional configuration of a close range photogrammetric system usually includes two calibrated cameras and a structured light projector, which has no need to be calibrated. If color texturing is needed additional color camera is applied. Using PC-controlled multi-media calibrated projector allows to increase productivity of a 3D reconstruction system and to reduce its cost due to including only one monochrome camera. Techniques for projector calibration and for 3D model color texturing are developed. Projector calibration is based on standard bundle adjustment technique traditionally used for camera calibration. The first approach uses two calibrated cameras for producing “virtual” spatial test field. The second method supposes generating synthetic “images” of a test field observed by the projector. Then the parameters of interior orientation for the camera and the projector are found by standard bundle adjustment procedure. 3D model color texturing performed by a set of monochrome images processing obtained in projector lighting. * 7, Victorenko str. Moscow, Russia 125319. Phone: +7 499 157 3127, Fax: +7 499 943 8605, e-mail: [email protected]