Advancements in the Development of DORIS

The airborne imaging system DORIS has undergone significant advancements since its first development in 1996 at Alberta Research Council, Alberta Canada. The system, which combines a laser scanner digital elevation model with simultaneously captured digital images, is used primarily to produce highly accurate high-resolution ortho-rectified image map for Forest Inventory and Management System. Besides its primary usage, DORIS image-map and the laser scanner digital elevation model provide a complete spatial base layer in a GIS system and can virtually serve all mapping applications requiring very high resolution and accurate three dimension spatial information. The DORIS system uses GPS/INS trajectory information to obtain the exterior orientation information of the camera exposure stations to directly geo-reference the acquired imagery. The development of the DORIS system involves integrating hardware components for data acquisition as well as developing processing software for processing the data. Whence, the DORIS system has two main components, namely, DORISia for data acquisition, and DORISpp for data pre-processing, and DORISpr for data processing. The components are integrated in a way to suite handling large data sets from the laser scanner and the digital camera. They also optimized for high performance under fully automated procedures from acquisition to image-map mosaic creation. The innovative concept of tiling is used throughout the automated scenario to speed up the overall processing of data. The pre-processing step in the DORIS system is intended to facilitate the processing of data. In this step, the trajectory information from the INS/GPS system is utilized along with the GPS event markers for the camera firing events are used to obtain the exposure station exterior orientation information. A coarse and fine alignment process is done in the pre-processing step to bring the camera and the laser scanner to align and hence produce highest quality possible. In this paper, advancements in the development of the DORIS system will be presented. Lab and field test results are presented to show the potential of the system. * Acronym for Differential Ortho-Rectification Imagery System