Image Processing and Gis Tools for Feature and Change Extraction

Currently the Centre for Topographic Information, Geomatics Canada, NRCan is involved in issue-based programs, such as the Geomatics for Northern Development and the Reducing Canada’s Vulnerability to Climate Change. As in many mapping organizations, the projects within these programs expect the delivery of geospatial data and information in much shorter time periods compared to operations in the past due to the external pressures and the availability of new data sources and technology. This increasing demand for delivery in shorter time imposes a need for rapid approaches for the extraction of topographic features and the detection of landscape changes from imagery. Considering the continuous dwindling of resources, the implementation of higher level of automation in the mapping operations is highly desirable to reduce both the production time and the cost involved, especially when dealing with the vast size of the Canadian territory. To implement rapid processes for mapping operations, such as feature recognition, feature extraction and change detection we have considered the possibilities offered by a) the new kinds of data sources and especially the availability of panchromatic and multispectral digital data; and b) the tools and techniques available in image processing (IP) and GIS packages respectively and how these tools can be used to accelerate the execution of mapping operations. Two case studies, one of which includes the application of CTI’s semi-automated change detection approach, are presented to demonstrate the potential, applicability and usefulness of this approach. * Corresponding author